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KISSPEPTINS 

Metabolic regulation of puberty 

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Neuroendocrine neoplasms 

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CLINICAL ONCOLOGY 

PROSTATE CANCER SCREENING 

Time for a rethink to avoid overtreatment 

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GASTROENTEROLOGY 

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ATRIAL ARRHYTHMIAS 

Role of the autonomic 

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Influence on cardiovascular risk 

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Systemic sclerosis 

Cellular and molecular mechanisms 

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Key Advances in Medicine 

The articles included in Nature Reviews Key Advances in 

Medicine were originally published in the February 2012 

issues of the eight clinical Nature Reviews journals. The journals’ 

editors commissioned international experts to write a short 

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Nature Reviews journals published 43 articles, which are collated 

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Nature Reviews Cardiology 

S1 acute coronary syndromes | Walking the tightrope between efficacy and bleeding 

Payal Kohli and Christopher P. Cannon 

S3 atrial fibrillation | Stroke prevention in AF 

Gregory Y. H. Lip 

S5 heart failure | Heart failure therapy—technology to the fore 

John J. V. McMurray 

S7 hypertension | New insights—from risk factors to treatment implications 

George L. Bakris 

S9 valvular disease | Breakthrough for intervention? 

Volkmar Falk 

Nature Reviews Clinical Oncology 

S11 ovarian cancer | Mutations and non-inferiority analyses show a way forward 

Maurie Markman 

S12 prostate cancer | Hitting old targets better and identifying new targets 

Yu Chen and Howard I. Scher 

S14 hematological cancer | New therapeutic targets and treatment strategies 

Paula Cramer and Michael Hallek 

S16 melanoma | A new paradigm tumor for drug development 

Alexander M. M. Eggermont and Caroline Robert 

S18 bone cancer | Prevention and treatment of bone metastases 

Robert E. Coleman

Nature Reviews Endocrinology 

S21 thyroid disease in pregnancy | Thyroid function—effects on 

mother and baby unraveled 

Anthony P. Weetman 

S22 primary aldosteronism | Towards a better understanding 

of causation and consequences 

Michael Stowasser 

S24 polycystic ovary syndrome | Genes, aging and sleep apnea 

in polycystic ovary syndrome 

Andrea Dunaif 

S26 epigenetics and metabolism | Epigenetics, the life-course 

and metabolic disease 

Peter D. Gluckman 

S28 osteoporosis | Osteoporosis therapy—dawn of the postbisphosphonate 

era 

Roland Baron 

S30 type 1 diabetes mellitus | Heterogeneity of T1DM raises questions 

for therapy 

Paolo Pozzilli 

Nature Reviews Gastroenterology & Hepatology 

S33 hepatitis c | A new standard of care and the race towards 

IFN-free therapy 

Wolf Peter Hofmann and Stefan Zeuzem 

S35 hepatocellular carcinoma | Genomics in hepatocellular 

carcinoma—a big step forward 

Ryosuke Tateishi and Masao Omata 

S36 ibd | Advances in IBD management—towards a tailored approach 

Guillame P. Pineton de Chambrun and William J. Sandborn 

S38 the gut microbiota | Translating the microbiota to medicine 

Fergus Shanahan 

S40 neurogastroenterology | Emerging concepts in 

neurogastroenterology and motility 

Keith A. Sharkey and Gary M. Mawe 

Nature Reviews Nephrology 

S43 glomerular disease | New clues to environmental influences 

in glomerular disease 

Peter J. Nelson and Charles E. Alpers 

S44 polycystic kidney disease | Connecting the dots toward a 

polycystic kidney disease therapy 

Vicente E. Torres and Peter C. Harris 

S46 acute kidney injury | Biomarkers are transforming our 

understanding of AKI 

Lakhmir S. Chawla and John A. Kellum 

S48 nondialysis chronic kidney disease | Progression, prediction, 

populations and possibilities 

Adeera Levin 

S50 dialysis | Can cardiovascular risk in dialysis patients be decreased? 

Peter Stenvinkel and Peter Bárány 

S52 transplantation | New agents, new ideas and new hope 

Titte R. Srinivas and Bruce Kaplan 

Nature Reviews Neurology 

S55 stroke | Major advances across the spectrum of stroke care 

Lee H. Schwamm 

S57 movement disorders | Translating new research findings into 

clinical practice 

Christine Klein and Dimitri Krainc 

S58 multiple sclerosis | Advances in therapy, imaging and risk factors 

in MS 

Bianca Weinstock-Guttman and Murali Ramanathan 

S60 dementia | Microbleeds in dementia—singing a different ARIA 

Philip Scheltens and Jeroen D. C. Goos 

S62 epilepsy | Insights into epilepsy treatments and biomarkers 

Fernando Cendes 

Nature Reviews Rheumatology 

S65 rheumatoid arthritis | Advances in diagnosis, treatment 

and definition of remission 

Gerd R. Burmester 

S67 juvenile idiopathic arthritis | New takes on categorization 

and treatment 

Alberto Martini 

S68 systemic lupus erythematosus | Deciphering the role of NETs 

and networks in SLE 

Thomas Dörner 

S70 osteoarthritis | Age-related OA—a concept emerging from infancy? 

Thomas Aigner and Wiltrud Richter 

S72 systemic sclerosis | From mechanisms to medicines 

Luc Mouthon 

S74 vasculitis | The renaissance of granulomatous inflammation in AAV 

Stephan D. Gadola and Wolfgang L. Gross 

Nature Reviews Urology 

S77 prostate cancer | Redefining the therapeutic landscape 

for CRPC 

Carmel Pezaro and Gerhardt Attard 

S79 bladder cancer | The dawn of personalized medicine 

Thomas W. Flaig and Dan Theodorescu 

S80 sexual dysfunction | Advances in epidemiology, pathophysiology 

and treatment 

Eric Chung and Gerald B. Brock 

S82 male factor infertility | Semen quality, sperm selection 

and hematospermia 

Amichai Kilchevsky and Stanton Honig 

S84 kidney cancer | Objectifying risk for localized renal masses 

Marc C. Smaldone and Robert G. Uzzo

CARDIOLOGY 

ACUTE CORONARY SYNDROMES IN 2011 

Walking the tightrope between efficacy 

and bleeding 

Payal Kohli and Christopher P. Cannon 

Major advances in the diagnosis of acute coronary syndromes (ACS) have occurred in 2011, but physicians 

treating ACS still walk the tightrope between efficacy and bleeding. Key publications have shed light on this 

delicate balance and heralded a new era of novel oral anticoagulants for the treatment of ACS. 

Kohli, P. & Cannon, C. P. Nat. Rev. Cardiol. 9, 69–71 (2012); published online 20 December 2011; doi:10.1038/nrcardio.2011.206 

The year 2011 has witnessed an evolution in 

all aspects of the management of acute coronary 

syndromes (ACS). The intro duction of 

new-generation troponin assays has complicated 

the diagnostic dilemma in ACS by 

increasing the number false positive diagnoses. 

One of the most-interesting studies 

of 2011 addressed whether the reduced 

threshold for detection of myocardial injury 

translated into improved clinical outcomes. 

Mills et al. undertook a prospective study of 

>1,000 patients who presented with possible 

ACS before and after the introduction of a 

lower diagnostic threshold (from 0.20 ng/ml 

to 0.05 ng/ml) for myocardial infarction (MI) 

using a high-sensitivity troponin assay with 

a low coefficient of variability (

CARDIOLOGY 

Events* per 1,000 patients 

15 – 

10 – 

5 – 

0 – 

–5 – 

–10 – 

–15 – 

APPRAISE–2 

P = NS 

P = NS 

Ef�cacy 

Safety 

P = 0.001 

P = 0.03 

particu larly favorably received. The investigators 

randomly assigned 15,526 patients 

with ACS to rivaroxaban 2.5 mg or 5.0 mg 

twice daily, or placebo on a background of 

aspirin alone (stratum 1) or aspirin plus a 

thienopyridine (stratum 2; 93% of patients). 

Notably, the doses of rivaroxaban used were 

much lower than that used for full anticoagulation, 

such as in atrial fibrillation (20 mg 

once daily). In the pooled cohort, a highly 

significant 16% relative risk reduction (8.9% 

vs 10.7%, P = 0.008) in cardiovascular death, 

MI, and stroke was observed for rivaroxaban, 

with a similar reduction in all-cause 

mortality, MI, and stroke (9.2% vs 11.0%, 

P = 0.006) and a 31% (2.3% vs 2.9%, P = 0.02) 

reduction in stent thrombosis over a 2-year 

period. A dose-dependent increase in TIMI 

major bleeding occurred (placebo: 0.6% vs 

rivaroxa ban 2.5 mg: 1.8% and rivaroxaban 

5 mg: 2.4%, P

5. Alexander, J. H. et al. Apixaban with antiplatelet 

therapy after acute coronary syndrome. N. Engl. 

J. Med. 365, 699–708 (2011). 

6. Mega, J. L. et al. Rivaroxaban in patients with 

a recent acute coronary syndrome. N. Engl. 

J. Med. http://dx.doi.org/10.1056/ 

NEJMoa1112277. 

7. Tricoci, P. et al. Thrombin-receptor antagonist 

vorapaxar in acute coronary syndromes. 

ATRIAL FIBRILLATION IN 2011 

Stroke prevention in AF 

Gregory Y. H. Lip 

In 2011, key trials with oral factor Xa inhibitors in patients with atrial 

fibrillation highlighted promising data on these novel anticoagulants. 

Patients with ≥1 stroke risk factors can be considered for oral 

anticoagulation. These novel, fixed-dose drugs are given without 

monitoring, so clinicians must learn to balance stroke and bleeding risks. 

Lip, G. Y. H. Nat. Rev. Cardiol. 9, 71–73 (2012); published online 20 December 2011; 

doi:10.1038/nrcardio.2011.203 

The year 2011 saw the publication of three 

pivotal phase III trials for two oral direct 

factor Xa inhibitors, apixaban and rivaroxaban, 

1–3 as well as important articles on bleeding 

risk assessment 4 and the net clinical 

benefit of thromboprophylaxis. 5 Novel oral 

anticoagulants that are viable alternatives to 

warfarin have clearly changed the landscape 

of stroke prevention in patients with atrial 

fibrillation (AF). 6 Until recently, the recommended 

approach was artificially to stratify 

patients with AF into low, intermediate, and 

high risk strata—despite stroke risk being a 

continuum—so that those classed as being 

at high risk could be targeted for an inconvenient 

(and potentially dangerous) drug, 

warfarin. Many studies, however, have shown 

that the categorization of patients into low, 

intermediate, or high risk strata has poor 

correlation with actual warfarin prescribing, 

and that the predictive value of risk 

schemes such as the CHADS 2 score (Box 1) 

to identify high-risk patients is suboptimal. 7 

Consequently, guidelines now recommended 

the use of the CHA 2 DS 2 -VASc score (Box 1) 

to complement the older (but simpler) 

CHADS 2 score. 

Indeed, emphasis is now directed towards 

identification of ‘truly low-risk’ patients with 

AF by being more inclusive (rather than 

exclusive) of common risk factors for stroke, 

because these patients might not need any 

antithrombotic therapy. Meanwhile, patients 

with ≥1 risk factor for stroke should be considered 

for effective stroke prevention with 

oral anticoagulation, whether with (very) 

well-controlled warfarin or one of the 

N. Engl. J. Med. http://dx.doi.org/10.1056/ 


8. Mathews, R. et al. In-hospital major 

bleeding during ST-elevation and 

non-ST-elevation myocardial infarction care: 

derivation and validation of a model from 

the ACTION Registry®-GWTG. 

Am. J. Cardiol. 107, 1136–1143 

(2011). 

novel agents, either an oral direct thrombin 

inhibitor (such as dabigatran) or an 

oral direct factor Xa inhibitor (for example, 

rivaroxaban or apixaban). 1 Indeed, the 

CHA 2 DS 2 -VASc score has consistently been 

shown to outperform the CHADS 2 score 

in identification of truly low-risk patients 

and is as good as—and possibly better 

than—the CHADS 2 score in the identification 

of high-risk patients who subsequently 

suffer thromboembolism. 7,8 

Key advances 

■ In the AVERROES trial, apixaban was 

superior to aspirin for stroke prevention 

in patients with atrial fibrillation (AF), 

with similar rates of major bleeding and 

improved tolerability 1 

■ In the ARISTOTLE trial, apixaban was 

superior to warfarin for prevention of 

stroke and systemic embolism in patients 

with AF, with significantly less major 

bleeding and improved survival 2 

■ In the ROCKET-AF trial, rivaroxaban was 

noninferior to warfarin for stroke prevention 

in a high-risk population of patients with 

AF, with similar rates of major bleeding 3 

■ The HAS-BLED score is well validated 

to predict major-bleeding events in 

patients receiving anticoagulation therapy, 

and outperforms other bleeding risk 

assessment schemes 4 

■ ‘Truly low-risk’ patients with a 

CHA 2 DS 2 -VASc score of 0 do not 

require thromboprophylaxis; net clinical 

benefit is greatest in patients with a high 

HAS-BLED score, where reduced ischemicstroke 

risk outweighs the increased 

intracranial-bleeding risk 5 

CARDIOLOGY 

Attention has also been directed to assessment 

of bleeding risk. Common risk factors 

for bleeding (as well as potentially correctable 

risk factors, such as uncontrolled blood pressure 

and concomitant aspirin use in patients 

receiving anticoagulation therapy) can 

inform clinical decision- making, especially 

with the novel oral anticoagulants that can 

come in high-dose and low-dose regimens. 9 

Investigators in the AVERROES trial 1 

studied 5,599 patients with AF and ≥1 risk 

factor for stroke, and who had refused warfarin 

or been deemed unsuitable for war farin 

by the investigators on the basis of the inclusion 

criteria. The trial was stopped early 

because of the clear superiority of apixaban 

over aspirin, with a 55% reduction in the 

primary end point of stroke and systemic 

embolism (HR 0.45, 95% CI 0.32–0.62, 

P

CARDIOLOGY 

Box 1 | Abbreviations and definitions 

CHADS2 Congestive heart failure (1 point) 

Hypertension (1 point) 

Age ≥75 years (1 point) 

Diabetes mellitus (1 point) 

Stroke or thromboembolism (2 points) 

CHA DS -VASc 

2 2 

Congestive heart failure (1 point) 

Hypertension (1 point) 

Age ≥75 years (2 points) 

Diabetes mellitus (1 point) 

Sex, female (1 point) 

Vascular disease (1 point) 

Age 65–74 years (1 point) 

Stroke or thromboembolism (2 points) 

HAS-BLED 

Hypertension (uncontrolled blood pressure) 

Abnormal renal or liver function 

Stroke 

Bleeding history or predisposition 

Labile international normalized ratio (INR) 

Elderly (age >65 years) 

Drugs concomitantly (for example, 

concomitant aspirin or nonsteroidal antiinflammatory 

drugs, or alcohol abuse) 

Net clinical benefit 

[ISR with no treatment – ISR on treatment] 

– 1.5*[IHR on treatment – IHR with 

no treatment] 

Abbreviations: IHR, intracranial-hemorrhage rate; 

ISR, ischemic-stroke rate. 

noninferior to warfarin for the primary end 

point of stroke and systemic embolism 

(HR 0.79, 95% CI 0.66–0.96, P

9. Lip, G. Y. H. et al. Bleeding risk assessment and 

management in atrial fibrillation patients: 

executive summary of a position document from 

the European Heart Rhythm Association [EHRA], 

endorsed by the European Society of Cardiology 

HEART FAILURE IN 2011 

Heart failure therapy—technology 

to the fore 

John J. V. McMurray 

Studies published in 2011 in the field of heart failure have reinforced 

the benefit of cardiac resynchronization therapy in patients with mild 

symptoms and confirmed the value of left ventricular assist devices and 

CABG surgery in selected patients. Conversely, the efficacy of nesiritide 

in acute heart failure has been questioned. 

McMurray, J. J. V. Nat. Rev. Cardiol. 9, 73–74 (2012); doi:10.1038/nrcardio.2011.212 

Although many interesting studies on 

epidemio logy, pathophysiology, and biomarkers 

in heart failure (HF) were published 

in 2011, my focus in this article is on 

treatments that are available for use and can 

make an impact in everyday practice. Five 

important studies, covering device and drug 

therapy, and surgery in patients with HF will 

be discussed. 

In August 2011, a follow-up report from 

MADIT-CRT 1 reinforced the impressive 

effect of cardiac resynchronization therapy 

(CRT) on outcomes among patients with 

HF, even in those with mild symptoms. The 

investigators showed that CRT plus a defibrillator, 

compared with a defibrillator alone, 

reduced the risk of a first episode of worsening 

HF by 46% (P

CARDIOLOGY 


■ Cardiac resynchronization therapy 

reduced not only the first, but also 

subsequent, episodes of worsening 

heart failure (HF) in patients with systolic 

dysfunction and mild symptoms 1 

■ Use of the HeartMate II® (Thoratec 

Corporation, Pleasanton, CA, USA) 

continuous-flow left ventricular assist 

device was associated with excellent 

6-month and 12-month survival in a 

’real-world’ registry study 2 

■ Pharmacological intervention prompted 

by noninvasive pulmonary artery 

monitoring may reduce the risk of 

HF hospitalization in patients with 

moderately severe symptoms and 

previous admission for HF 4 

■ In selected patients with ischemic 

systolic HF and a life expectancy of more 

than 2 years, CABG surgery may reduce 

cardiovascular mortality and morbidity 6 

■ Nesiritide has a small and clinically 

insignificant effect on dyspnea and no 

effect on mortality or worsening HF in 

patients with acute HF 7 

6 months in the intervention group, meaning 

that eight patients needed to be treated to 

prevent one hospitalization. 4 Although 

these results are impressive, the trial has 

been criticized because of the active involvement 

of the sponsor in encouraging treatment 

changes in the intervention group, and 

whether the benefit would be as substantial 

when used in ordinary practice has been 

questioned. Nevertheless, the positive findings 

of the CHAMPION trial 4 contrasted 

strikingly with those of other studies, such 

as the negative study DOT-HF 5 in which 

an implantable intrathoracic impedance 

detection device was used. 

Another study that raised as many questions 

as answers was the STICH trial. 6 In this 

study, 1,212 patients with a left ventric ular 

ejection fraction

HYPERTENSION IN 2011 

New insights—from risk factors 

to treatment implications 

George L. Bakris 

The results of several hypertension studies published in 2011 have 

contributed to our knowledge on the risks of and treatment for this 

condition, including the effects of slow-wave sleep, nocturnal dosing 

of medication, variability in post-stroke blood-pressure reduction, 

and the impacts of a low-sodium diet. 

Bakris, G. L. Nat. Rev. Cardiol. 9, 75–77 (2012); published online 13 December 2011; 

doi:10.1038/nrcardio.2011.202 

Four key studies, completed and published 

in 2011, should affect the evaluation of 

patients with hypertension and practice patterns 

in this population. In one such trial, 

conducted in Spain, medications were dosed 

at night in order to improve the dipping 

status of blood pressure (BP). In this trial 

661 patients with hypertension who were 

at various stages of chronic kidney disease 

(CKD) were randomly assigned to take all 

prescribed hypertension medications upon 

awakening or at least one drug before going 

to bed. 1 At the end of follow-up (median 

5.4 years), patients who took the nocturnal 

dose had an adjusted risk for total cardiovascular 

events that was approximately onethird 

that of patients who took medication 

upon awakening. 1 Patients who received 

nocturnal treatment also had a significantly 

lower mean BP during sleep and a greater 

proportion of these indivi duals demonstrated 

controlled ambulatory BP compared 

with those taking medication upon awakening. 

1 These data are consistent with those 

from a shorter-term study of patients with 

stage 2–3 CKD and no signifi cant proteinuria. 

2 However, a pilot study in the African 

American Study of Kidney Disease (AASK) 

cohort of ~100 patients with stage 4 CKD 

and proteinuria using similar methodo logy 

as the Spanish group failed to show this 

benefit on BP dipping status or BP control 

in the morning after 1 year of dosing antihypertensive 

medications at night. 3 One of 

the major differences between the studies 

was that 100% of the patients in the AASK 

cohort had proteinuria at various levels and 

stage 4 nephropathy, whereas only about 

10% of the patients in the Spanish study fit 

this description. A nocturnal dosing strategy 

was also tested in the large CONVINCE 

trial, 4 but failed to show a reduction in 

cardio vascular risk. However, the CKD and 

dipping status of the individuals enrolled in 

the trial was unknown. Given the increased 

cardiovascular risk among patients with 

stage 3 CKD, ambulatory BP monitoring 

(ABPM) is required to assess dipping status 

and indivi dualize dosing regimens in people 

who meet the criteria as nondippers. As 

yet no ABPM data are available from large 

cohorts with stage 4 CKD and so the recommendation 

cannot be extended to this group 

of patients. 

The second major advance in 2011 was 

the finding of an association between poor 

sleep quality and the development of hypertension. 

5 This relationship is unrelated to 

sleep apnea and has more to do with the 

amount and type of sleep. Fung et al. evaluated 

whether incident hypertension is 

associ ated with polysomnography measures 

of sleep-disordered breathing, sleep duration, 

and sleep architecture in older men 

(mean age 75 years). 5 Participants included 

784 community-dwelling, ambulatory men 

from the Outcomes of Sleep Disorders 

in Older Men Study who did not have 


■ Among patients with moderate-stage 

nephropathy, dosing medications at night 

has the advantage of improving blood 

pressure (BP) goal attainment in the 

early morning when cardiovascular risk 

is highest 1 

■ Failure to recognize insufficient quality of 

sleep secondary to frequent disturbances 

of awakening is a major contributing 

risk for hypertension development and 

poor BP control 5 

■ Lowering BP by more than 15–20% in 

patients with hypertension early in the 

post-stroke period can result in long-term 

cognitive consequences 6 

■ Low-sodium diets clearly reduce BP, but 

tend only to reduce cardiovascular events 

in trials; in populations, low-sodium diets 

reduce mortality 8 

CARDIOLOGY 

hypertension at the time of their in-home 

sleep studies and who returned for followup 

after 2–4 years. By the end of follow-up 

(mean 3.4 years), 243 men met the criteria 

for incident hypertension. After adjustment 

for age, nonwhite race, study site, and 

BMI, the only sleep index to remain significantly 

associated with incident hyper tension 

was decreased stage N3 (or slow-wave) 

sleep. No attenuation of this association was 

seen after accounting for sleep duration, 

sleep fragmentation, and indices of sleepdisordered 

breathing. Thus, failure to get 

an appropriate amount of slow-wave sleep 

each night is a risk factor for development 

of hyper tension. Reduced amounts of slowwave 

sleep are seen commonly in elderly 

patients and could be related to increased 

frequency of waking to urinate. Physicians 

should be aware of decreased deep sleep as a 

risk factor for hypertension and ensure that 

patients get an extended rest period at night 

by decreasing stimuli, such as caffeine and 

liquid intake. This strategy is used in my 

practice with a fair amount of success. 

A third important trial published in 2011 

provides new information on the consequences 

of aggressive BP management 

in the setting of acute stroke. In SCAST, 6 

2,029 patients from northern Europe with 

acute ischemic or hemorrhagic stroke and 

systolic BP >140 mmHg were randomly 

assigned within 30 h of symptom onset to 

cande sartan or placebo for 7 days. The dose 

was increased from 4 mg on day 1 to 16 mg 

on days 3–7. During the 7-day treatment 

period, BP was 5/2 mmHg lower in the candesartan 

group than in the placebo group 

(mean BP 147/82 mmHg vs 152/84 mmHg). 

At the end of the 6 month follow-up, the risk 

of the primary composite vascular end point 

did not differ between treatment groups. 

The co-primary end point of functional 

outcome (modified Rankin scale), however, 

was associ ated with a higher risk of poor 

outcome in the candesartan group. The 

results were interpreted by the investigators 

to suggest some harm and no benefit for BP 

lowering after acute stroke. 6 

To understand this finding, clinicians 

should be aware that current BP guidelines 

for the post-stroke period differ according 

to whether the stroke is hemorrhagic 

or ischemic. 7 In addition, the approach 

to BP management for the prevention of 

stroke is totally different from its management 

post stroke. In hemorrhagic stroke, 

current guidelines suggest cautious lowering 

of BP by no more that 20% in the 

first 24 h. 7 Agents with rapid, short-term 

KEY ADVANCES IN MEDICINE JANUARY 2012 | S7

CARDIOLOGY 

© Elena Babushkina | Dreamstime.com 

action such as labetalol, nicardipine, and 

fenoldapam are preferred as nitroglycerin 

and nitroprusside can increase intra cranial 

pressure. For patients with ischemic stroke 

who are not receiving thrombolytic therapy, 

BP should be lowered if markedly elevated 

(>220/120 mmHg). 7 In SCAST, baseline 

BP was 171/90 mmHg, 6 so a reduction to 

~140 mmHg is excessive given the recommendation 

and, therefore, the lack of benefit 

is not surprising. 

The fourth notable study published in 

2011 is a meta-analysis in which the investigators 

aimed to assess the long-term effects 

of dietary salt reduction on mortality and 

cardiovascular morbidity and whether BP 

reduction is an explanatory factor in any 

effect of such dietary interventions. 8 A total 

of 7 studies were included, 3 in normotensive 

individuals, two in patients with 

hyper tension, one in a mixed population, 

and one in patients with heart failure with 

end of trial follow-up of 7–36 months and 

longest observational follow up to 12.7 years. 

The data failed to show strong evidence 

for a reduced risk of all-cause mortality or 

cardio vascular morbidity in normo tensive 

indivi duals and patients with hyper tension 

on low-salt diets. The investigators suggest 

their review had insufficient power to 

exclude clinically important effects, since 

only 665 deaths occurred in 6,250 participants. 

They further state that their estimates 

of benefits from dietary salt restriction are 

consistent with the predicted small effects 

on clinical events attributable to the small 

BP reduction achieved. 

This information puts into perspective the 

limitations of clinical trials. The evidence 

that salt reduction lowers BP is clear and 

consistent. Since BP reduction is critical for 

reducing the risk of stroke and progression of 

CKD, low-salt diets should also be of benefit. 

However, most people do not consistently 

maintain a low sodium intake leading to 

fluctu ation in BP, which is a major risk factor 

for stroke. The real impact of low sodium 

intake on mortality has been demonstrated in 

Japan and Finland where sodium reduction 

policies have been instituted for all foods sold 

in stores. In the USA, reducing dietary salt by 

3 g per day is projected to reduce the annual 

number of all-cause deaths from 44,000 to 

92,000. 9 Hence, large numbers of individuals 

and years of follow-up are required to 

see the effect of consistent reduced sodium 

intake. Not surprisingly, therefore, trial data 

and even meta- analyses cannot adequately 

demon strate these effects. Clinicians should 

focus on the established fact that BP reduction 

is consistently associ ated with reductions 

in cardio vascular event rates and continue to 

stress the importance of a low-sodium diet 

to patients with hypertension. 

Finally, the multicenter, prospective, randomized 

Symplicity HTN-2 trial, which 

was published in late 2010, 10 provided 

ground-breaking results for a new concept 

of treatment for refractory hypertension. 

Participants with systolic BP ≥160 mmHg (or 

≥150 mmHg for those with type 2 diabetes 

mellitus) were randomly allocated to undergo 

renal denervation together with continuation 

of previous treatment or maintain previous 

treatment alone. Office-based BP measurements 

were reduced by 32/12 mmHg (baseline 

178/96 mmHg) in the renal denervation 

group, control group BP values did not differ 

from the baseline of 178/97 mmHg, and 

between-group differences in BP at 6 months 

were 33/11 mmHg. No serious procedure or 

device-related complications occurred and 

adverse events did not differ between groups. 

The investi gators concluded that catheterbased 

renal denervation is a safe and viable 

treatment for patients who cannot achieve 

BP goals with pharmaco therapy. 10 In 2011, 

recruitment for the Symplicity HTN-3 trial 

started in the USA; with a protocol that is 

more stringent than Symplicity HTN-2 and 

involves more frequent ABPM. This new 

trial will include between-group differences 

in ABPM as a prespecified secondary end 

point. Hypertension management prior to 

study enrollment will be more intense and 

will include spironolactone. If the results of 

the Symplicity HTN-3 trial are as gratifying 

as that of Symplicity HTN-2, a true alternative 

to medications will exist for refractory 

hypertension. Many other ongoing clinical 

trials have been designed to address and, 

hopefully, answer important questions 

about specific approaches to reducing cardiovascular 

risk and the progression of CKD in 

patients with hypertension. 

Hypertensive Diseases Unit, Section of 

Endocrinology, Diabetes and Metabolism, 

Department of Medicine, University of Chicago 

Pritzker School of Medicine, 5841 South 

Maryland Avenue, MC 1027, Chicago, 

IL 60637, USA. 

gbakris@medicine.bsd.uchicago.edu 

Competing interests 

The author declares associations with the following 

companies: Abbott, CVRx, Eli Lilly, FDA, Forest 

Laboratories, Johnson & Johnson, Medtronic, 

Novartis, Relypsa, Servier, and Takeda. See the 

article online for full details of the relationships. 

1. Hermida, R. C., Ayala, D. E., Mojon, A. 

& Fernandez, J. R. Bedtime dosing of 

antihypertensive medications reduces 

cardiovascular risk in CKD. J. Am. Soc. Nephrol. 

http://dx.doi.org/10.1681/ASN.2011040361. 

2. Minutolo, R. et al. Changing the timing of 

antihypertensive therapy to reduce nocturnal 

blood pressure in CKD: an 8-week uncontrolled 

trial. Am. J. Kidney Dis. 50, 908–917 (2007). 

3. Rahman, M. & Appel, L. J. Should reducing 

nocturnal blood pressure be a therapeutic 

target in CKD? The time is ripe for a clinical 

outcomes trial. Am. J. Kidney Dis. 50, 901–903 

(2007). 

4. Black, H. R. et al. Principal results of the 

Controlled Onset Verapamil Investigation 

of Cardiovascular End Points (CONVINCE) trial. 

JAMA 289, 2073–2082 (2003). 

5. Fung, M. M. et al. Decreased slow wave sleep 

increases risk of developing hypertension in 

elderly men. Hypertension 58, 596–603 (2011). 

6. Sandset, E. C. et al. The angiotensin-receptor 

blocker candesartan for treatment of acute 

stroke (SCAST): a randomised, placebocontrolled, 

double-blind trial. Lancet 377, 

741–750 (2011). 

7. Aiyagari, V. & Gorelick, P. B. Management of 

blood pressure for acute and recurrent stroke. 

Stroke 40, 2251–2256 (2009). 

8. Taylor, R. S., Ashton, K. E., Moxham, T., 

Hooper, L. & Ebrahim, S. Reduced dietary salt 

for the prevention of cardiovascular disease: 

a meta-analysis of randomized controlled trials 

(Cochrane review). Am. J. Hypertens. 24, 

843–853 (2011). 

S8 | JANUARY 2012 www.nature.com/reviews

9. Bibbins-Domingo, K. et al. Projected effect of 

dietary salt reductions on future cardiovascular 

disease. N. Engl. J. Med. 362, 590–599 

(2010). 

VALVULAR DISEASE IN 2011 

Breakthrough for intervention? 

Volkmar Falk 

In 2011, both the PARTNER-A trial, in high-risk patients with severe aortic 

stenosis, and EVEREST II, in patients with mitral insufficiency, showed 

noninferiority of transcatheter interventions compared with surgery for 

the chosen primary end points. However, both of the trials, and important 

registry data, identified limitations of transcatheter valve interventions. 

Falk, V. Nat. Rev. Cardiol. 9, 77–78 (2012); published online 20 December 2011; 

doi:10.1038.nrcardio.2011.204 

Data from two major randomized, controlled 

trials in which interventional 

therapy was compared with conventional 

surgery for the treatment of aortic stenosis 

in high-risk patients 1 and for selected 

patients with mitral insufficiency 2,3 were 

published in 2011. Both trials showed noninferiority 

for their respective primary end 

points, but (together with data from national 

registries 4,5 ) also highlighted limitations of 

interventional therapy. 

The most-important trial in the field of 

valvular heart disease that was published in 

2011 was the PARTNER-A trial, 1 in which 

transcatheter aortic-valve implantation 

(TAVI) was compared with surgical aorticvalve 

replacement (SAVR) in a high-risk 

population of patients with severe aortic 

stenosis. From a total of 3,105 screened 

patients, 699 individuals (23%) were randomly 

allocated to either SAVR (n = 351) or 

TAVI (n = 348, transfemoral or trans apical) 

using the Edwards SAPIEN® (Edwards 

Lifesciences Corporation, Irvine, CA, USA) 

balloon-expandable valve. Patients were 

considered high risk on the basis of coexisting 

conditions associated with a risk of death 

≥15% at 30 days. In the intention-to-treat 

analysis, death from any cause (the primary 

end point) was not different between the 

TAVI and SAVR groups at 30 days (3.4% vs 

6.5%, respectively) or 1 year (24.2% vs 26.8%, 

respectively), which led to the conclusion that 

TAVI was non inferior to SAVR. Patients in 

the TAVI group had a shorter length of stay 

in the intensive-care unit and a shorter index 

hospitalization compared with patients 

undergoing SAVR. 

Bleeding and new onset of atrial fibrillation 

were more frequent in the surgical 

group, whereas rates of vascular and 

neuro logical complications were higher in 

10. Esler, M. D. et al. Renal sympathetic denervation 

in patients with treatment-resistant hypertension 

(the Symplicity HTN-2 trial): a randomised 

controlled trial. Lancet 376, 1903–1909 (2010). 

the TAVI group. The rates of major stroke 

were 3.8% and 2.1% at 30 days, and 5.1% 

and 2.4% at 1 year, in the TAVI and surgical 

groups, respectively. At 1 year, TAVI 

was associated with a lower mean aorticvalve 

gradient compared with the surgical 

group, but with a higher rate of moderate or 

severe paravalvular regurgitation at 30 days 

(12.2% vs 0.9%) and 1 year (6.8% vs 1.9%). 

Functional improvement was significant 

for both groups after 1 year and not different 

between the groups. The results 

of the PARTNER-A trial 1 demonstrate 

that TAVI is not only superior to medical 

therapy in non surgical candidates, but also a 

true alternative to surgical replacement for 

a selected, high-risk subgroup of patients 

with aortic stenosis. 

Data from a number of national TAVI registries 

were published in 2011. The FRANCE 

registry 6 included data on 244 patients who 

received an Edwards SAPIEN® (68%) or 

CoreValve® (Medtronic CV Luxembourg 

S.a.r.l., Luxembourg; 32%) in 2009. Device 

success rate was 98.3% and 30-day mortal ity 


■ In high-risk patients with severe aortic 

stenosis, transcatheter aortic-valve 

implantation (TAVI) can be performed 

with similar 1-year survival and functional 

outcomes as conventional surgery 1 

■ Moderate and severe paravalvular 

leakage after TAVI is an independent 

predictor of late mortality 4,5 

■ Percutaneous edge-to-edge mitral-valve 

repair can be safely performed with low 

periprocedural complications 2 

■ Residual moderate mitral regurgitation 

is more frequent after percutaneous 

edge-to-edge repair than surgery and 

might impair long-term results 3 

CARDIOLOGY 

was 12.7%. Stroke and vascular complications 

occurred in 3.6% and 7.3% of patients, 

respectively. Data from the FRANCE 2 registry, 

7 which included 2,419 patients treated 

between January 2010 and July 2011, were 

presented at the ESC Congress in 2011. 

Device success rate was 97.1%, and 30-day 

and 6-month mortality were 9.9% and 

17.2%, respectively. The stroke rate of 4.0% 

was similar to the rates reported in the 

PARTNER trials. 1 The high incidence of 

stroke after TAVI is concerning, and might 

result from a substantial embolic load during 

the TAVI procedure, as has been demonstrated 

using transcranial Doppler imaging 

during implantation and cerebral MRI after 

the procedure. 

The UK TAVI registry 8 included 890 

patients. Procedural success (97.2%) and 

stroke rate (4.1%) were similar to the French 

experience. Mortality at 30 days was 7.1%, and 

1-year and 2-year survival were 78.6% and 

73.7%, respectively. A degree of paravalvular 

aortic regurgitation (AR) regarded as suboptimal 

or unacceptable occurred in 61% of 

patients. The presence of moderate or severe 

AR (13% of patients) was an independent 

predictor of mortality at 1 year. 

In the German TAVI registry, 4 which 

comprised 690 patients (84% Medtronic 

CoreValve® system), the rate of AR ≥2 

was 17.2% and its presence was a strong, 

in dependent predictor of in-hospital death 

(adjusted OR 2.43). In the Italian, multicenter 

registry 5 of 663 patients who underwent 

transfemoral TAVI with the third-generation 

18 Fr CoreValve® device, the rate of paravalvular 

leak ≥2 after implantation was 21%, 

and independently associated with mortality 

between 30 days and 1 year (HR 3.79). 

Therefore, data from three national registries 

have shown that paravalvular leakage is an 

independent risk factor for mortality after 

TAVI. 4,5,8 The development of improved prosthetic 

implants and implantation techniques 

is required. 

In the absence of long-term follow-up data 

after TAVI, the results of the PARTNER-A 

trial 1 and the data from the national registries 

4–8 must be interpreted with caution. 

Recommendations to individual patients 

must balance the obvious advantages of 

a less-invasive transcatheter approach 

compared with SAVR, with the increased 

risk of stroke and unfavorable long- 

term consequences of paravalvular leakage 

after TAVI. 

The landmark mitral-valve trial published 

in 2011 was EVEREST II. 2 In total, 

279 patients with severe mitral regurgitation 


CARDIOLOGY 

V 

a b 

10 

Figure 1 | Images from a patient in NYHA class IV because of ischemic cardiomyopathy with 

poor LV ejection fraction (2+ at 12 months) was met, despite 

the fact that 18.5% and only 3% of patients 

had residual mitral insufficiency >2+ at 

1 year in the MitraClip® and surgical groups, 

respectively. Another 33% of patients in the 

MitraClip® group had residual mitral insufficiency 

= 2+, and more than 15% of patients 

in the device arm subsequently underwent 

mitral-valve surgery because of persistent, 

severe MR. 

The arbitrary end point of freedom from 

mitral insufficiency >2+ has triggered lively 

discussion. Residual mitral insufficiency 

>1+ after mitral repair is clearly unacceptable, 

and is an independent predictor of 

late mortality. If the EVEREST II investigators 

had chosen presence of mitral insufficiency 

2+ as part of the effectiveness 

end point, fewer than half of the 

patients (47.9%) treated with the MitraClip® 

would have fulfilled the combined criteria. 

Statistical noninferiority for effectiveness 

at 1 year was reached by definition, but the 

debate whether this result can be regarded 

as noninferior from a clinical perspective is 

likely to continue—particularly because the 

intention-to-treat analysis revealed that 

the primary composite end points at 2 years 

were still significantly better with surgery 

than percutaneous intervention. 3 Longterm 

data are needed before the indication 

for this therapy can be extended to patients 

with degenerative mitral-valve disease, in 

whom the success rate of endoscopic surgical 

mitral-valve repair is >95%, with excellent 

short-term and long-term results. 9 Mitralvalve 

repair after previous clip placement 

is often not possible because the device is 

encapsulated over time by fibrous tissue; 

the use of the MitraClip® should, therefore, 

be restricted to patients who are at high 

surgical risk. 

The unconvincing long-term results of 

downsizing annuloplasty in patients with 

severe leaflet tethering make the MitraClip® 

an attractive option in patients with functional 

MR. In the PERMIT trial, 10 51 severely 

symptomatic nonresponders to cardiac 

resynchronization therapy with severe left 

ventricular dysfunction and functional MR 

underwent treatment with the MitraClip®. 

Residual MR ≥2+ was present in


OVARIAN CANCER IN 2011 

Mutations and non-inferiority analyses show 

a way forward 

Maurie Markman 

Highly clinically relevant ovarian cancer clinical research in 2011 focused on an increased understanding of the 

biology of the malignancy, limitations of strategies for early detection and screening, and the provocative reports of 

alternative primary and second-line management strategies. 

Markman, M. Nat. Rev. Clin. Oncol. 9, 69–70 (2012); published online 20 December 2011; doi:10.1038/nrclinonc.2011.200 

Although there were a number of very interesting 

preliminary reports of thera peutic 

advances in ovarian cancer in 2011 (for 

example, bevacizumab in the first-line and 

second-line management of the malignancy, 

and olaparib as maintenance therapy for 

high-grade serous cancers), as of the writing 

of this commentary these studies have not 

appeared in the peer-reviewed oncology literature. 

Despite the absence of major advances 

in the realm of treatment, several papers 

published in 2011 provide highly clinically 

relevant insight into the management and 

unique biology of ovarian cancer. 

Perhaps the most important paper in 

2011 was the long-awaited final report from 

the Prostate, Lung, Colorectal and Ovarian 

(PLCO) cancer screening randomized controlled 

trial dealing specifically with ovarian 

cancer. 1 The study, involving 78,000 women 

with ages ranging from 55 to 74 years, randomly 

assigned participants to what was 

classified as ‘usual care’ or a rather-intensive 

screening strategy that included annual 

serum CA125 determinations and transvaginal 

ultrasounds. It should be noted that 

this study did not specifically target women 

identified as being at ‘high risk’ for the 

develop ment of ovarian cancer (for example, 

those with a family history of ovarian cancer). 

The screening protocol, undertaken from 

November 1993 to July 2001, was performed 

at one of 10 centers in the USA and the 

median follow-up period for the population 

was 12.4 years, with patients being followed 

until death or for a maximum of 13 years. 

The primary study end point was the rate 

of mortality from ovarian cancer (including 

primary peritoneal or fallopian tube cancer), 

with secondary end points of disease incidence 

and complications associ ated with 

Table 1 | Influence of BRCA1 or BRCA2 on outcome in high-grade serous ovarian cancer 6 

Mutational status 3-year 

PFS (%) 

5-year 

PFS (%) 

the screening strategy. The study revealed 

no difference in deaths from ovarian cancer 

or other causes between the screening and 

usual-care groups. Specifically, there were 

212 cases of ovarian cancer and 118 deaths 

from the malignancy in the screening group 

versus 176 cases and 100 deaths in the routine-care 

population. Furthermore, and of 

considerable relevance, 1,080 surgeries were 

performed among the 3,285 women with 

false-positive screening tests, and 163 of 

these individuals developed at least a single 

‘serious complication’. 1 

The important data from this screening 

trial provide no support for the routine use 

of annual CA125 determinations or vaginal 

ultrasounds for completely asymptomatic 

women as a screening strategy to detect 

ovarian cancer. However, it is again rele vant 

to acknowledge that this trial did not specifically 

address the issue of screening a more 

high-risk population, nor did it attempt to 

define the utility of these tests in the detection 

of ovarian cancer in indivi duals presenting 

with symptoms (for example, several 

weeks of persistent mild abdominal pain). 

A study that is somewhat related to the 

PLCO trial attempted to address the important 

question of whether an earlier diagnosis 

of ovarian cancer in a sympto matic 

individual might be associated with an 

improved outcome. 2 Australian investigators 

HR compared 

with WT patients 

3-year 

OS (%) 

5-year 

OS (%) 

HR compared 

with WT patients 

BRCA1 mutation 22 13 0.81 (P = 0.44) 64 44 0.76 (P = 0.35) 

BRCA2 mutation 44 39 0.40 (P = 0.004) 83 61 0.33 (P = 0.003) 

BRCA WT 16 10 – 58 25 – 

Abbreviations: HR, hazard ratio; OS, overall survival; PFS, progression-free survival; WT, wild type. 

retrospectively examined the survival of 1,300 

patients with ovarian cancer seen by a physician 

within varying time intervals (55%, 70% 

and 92% of the women presented within 1, 

2 and 6 months, respectively) from the onset 

of their initial symptoms. The investigators 

were unable to find any difference in survival 

based on the duration of symptoms before 

the time of diagnosis. Importantly, these data 

do not support the hypothesis that a somewhat 

earlier diagnosis (timeline measured 

in ‘months’) will be associ ated with superior 

ovarian cancer-specific survival, 3 although 

the more-timely recognition of the correct 

diagnosis will likely result in more-rapid initiation 

of a management plan that will hopefully 

favorably impact serious symptoms and 

the individual’s overall quality of life. 

It is well established that mutations in 

BRCA1 and BRCA2 are associated with an 

increased lifetime risk for the development 

of ovarian cancer. 4 Furthermore, highly 

provocative data from a number of ovarian 

cancer investigators have suggested that 

within the population of women with documented 

advanced-stage ovarian cancer, 

patients with BRCA mutations experience 

an overall superior survival (compared with 

patients with wild-type BRCA), a difference 

that is possibly related to increased sensitivity 

to platinum-based chemotherapy. 5 In 

a most-provocative report, investigators 




■ There are currently no evidence-based 

data supporting the clinical utility of any 

ovarian cancer screening strategy in 

non-high-risk populations 1 

■ Provocative data suggest there may be a 

clinically meaningful difference between 

the presence of a BRCA1 or a BRCA2 

mutation in influencing outcome in ovarian 

cancer 6 

■ Under specific circumstances (for example, 

neuropathy) it might be reasonable to 

substitute pegylated liposomal doxorubicin 

for paclitaxel in the front-line chemotherapy 

management of ovarian cancer 7 

conducted an observational study involving 

316 women with high-grade serous ovarian 

cancer whose BRCA mutational status was 

established, to evaluate the impact of such 

mutations on outcome. 6 Although the total 

sample size was limited (37 and 29 patients 

with BRCA1 and BRCA2 mutations, respectively), 

there was a rather striking difference 

in both the inherent chemosensitivity and 

survival between the two mutation groups, 

and compared with women without mutations 

(Table 1). Patients with BRCA2 mutations 

experienced a statistically significant 

improvement in 5-year survival compared 

with BRCA1 deficient and BRCA ‘wild-type’ 

cases. Although these results will need to be 

confirmed by other investigative groups with 

larger sample sizes, they suggest the potential 

that these two genetic abnormalities might 

exert quite different influences on outcome 

in high-grade serous ovarian cancer. At the 

present time, there are no known thera peutic 

implications associated with these findings, 

but it is possible that future research may 

result in recommendations for different 

management strategies for patients with 

BRCA1 or BRCA2 mutations. 

Finally, it is relevant to note an interesting 

(although unfortunately flawed) phase III 

randomized trial that directly compared 

a regimen of carboplatin plus paclitaxel to 

carboplatin plus pegylated liposomal doxorubicin 

as primary treatment for epithelial 

ovarian cancer. 7 Although this potentially 

paradigm changing study included a total 

of 820 patients, it was specifically designed 

to demonstrate the therapeutic superiority 

(rather than non-inferiority with possibility 

an improved toxicity profile) of the investigative 

pegylated liposomal doxorubicincontaining 

regimen. In fact, although the 

study demonstrated similar median progression-free 

survival times (19.0 months 

and 16.8 months) and median overall survival 

times (61.6 months and 53.2 months) 

for the carboplatin–pegylated liposomal 

doxorubicin and carboplatin–paclitaxel 

study arms, respectively, the trial failed to 

achieve its primary end point (the documentation 

of ‘superiority’ for the experimental 

arm over the established therapy arm). As a 

result of this failure, the investigators appropriately 

concluded that the investigative 

regimen “was not superior to carboplatin– 

paclitaxel which remains the standard firstline 

chemo therapy for advanced ovarian 

cancer.” 7 However, it is reasonable to suggest 

that for patients unable to tolerate the taxane 

(for example, patients who develop neuropathy 

early in the treatment course or severe 

paclitaxel-associated hypersensitivity reaction) 

the substitution of pegylated liposomal 

doxorubicin is not an unreasonable option. 

Thus, it is reasonable to characterize the 

ovarian cancer peer-reviewed literature in 

2011 as providing modestly useful information 

regarding disease management and 

including important discussions of the limitations 

in our ability to modify the relatively 

early natural history of the malignancy. It 

is rather striking that in a clinical research 

world where unique targets have been discovered 

in multiple cancers (for example, 

HER2 overexpression in breast cancer, EGFR 

mutations in lung cancer, and BRAF mutations 

in melanoma) leading to exciting new 

treatment strategies, there remain no such 

molecular targets in ovarian cancer, the 

presence of which would lead to specific 

management paradigms to favorably impact 

outcome. It is clear that much work needs 

PROSTATE CANCER IN 2011 

Hitting old targets better 

and identifying new targets 

Yu Chen and Howard I. Scher 

to be done to improve our understanding of 

the fundamental biology of ovarian cancer 

to change this current state-of-affairs. 

Cancer Treatment Centers of America, Eastern 

Regional Medical Center, 1331 East Wyoming 

Avenue, Philadelphia, PA 19124, USA. 

maurie.markman@ctca-hope.com 


The author declares an association with the 

following company: Genentech. See the article 

online for full details of the relationship. 

1. Buys, S. S. et al. Effect of screening on ovarian 

cancer mortality: the Prostate, Lung, Colorectal 

and Ovarian (PLCO) cancer screening 

randomized controlled trial. JAMA 305, 

2295–2303 (2011). 

2. Nagle, C. M. et al. Reducing time to diagnosis 

does not improve outcomes for women with 

symptomatic ovarian cancer: a report from the 

Australian Ovarian Cancer Study Group. J. Clin. 

Oncol. 29, 2253–2258 (2011). 

3. Anderson, M. R. et al. Combining a symptoms 

index with CA125 to improve detection of 

ovarian cancer. Cancer 113, 484–489 (2008). 

4. King, M. C. et al. Breast and ovarian cancer 

risks due to inherited mutations in BRCA1 and 

BRCA2. Science 302, 643–646 (2003). 

5. Tan, D. S. et al. “BRCA-ness” syndrome in 

ovarian cancer: a case-control study describing 

the clinical features and outcome of patients 

with epithelial ovarian cancer associated with 

BRCA1 and BRCA2 mutations. J. Clin. Oncol. 

26, 5530–5536 (2008). 

6. Yang, D. et al. Associations of BRCA1 and 

BRCA2 mutations with survival, chemotherapy 

sensitivity, and gene mutator phenotype in 

patients with ovarian cancer. JAMA 306, 

1557–1565 (2011). 

7. Pignata, S. et al. Carboplatin plus paclitaxel 

versus carboplatin plus pegylated liposomal 

doxorubicin as first-line treatment for patients 

with ovarian cancer: The MITO-2 randomized 

phase III trial. J. Clin. Oncol. 29, 3628–3635 

(2011). 

Options to treat late-stage castration-resistant prostate cancer continued 

to increase in 2011, as three agents with different mechanisms of 

action prolonged life and a fourth reduced the morbidity of skeletal 

metastases. These outcomes contrasted with the heightened controversy 

generated by the recommendation against PSA screening and other early 

detection strategies. 

Chen, Y. & Scher, H. I. Nat. Rev. Clin. Oncol. 9, 70–72 (2012); published online 10 January 2012; 

doi:10.1038/nrclinonc.2011.213 

In the Western world, one in six men will 

be diagnosed with prostate cancer and, 

of these, one in six will die of metastatic 

disease. Improving outcomes for men with 

prostate cancer depends on the one hand 

on developing more-effective systemic 

therapies and, on the other hand, on early 

diagnosis and treatment, before the disease 

has metastasized. 

2011 is the 70 th anniversary of when 

Charles Huggins established that prostate 

cancer is an androgen-dependent 


malignancy and, until recently, docetaxel was 

the only non-hormonal therapy to prolong 

life. In 2010, sipuleucel-T and cabazitaxel 

were shown to confer a survival benefit and 

were subsequently approved by the FDA. 

This trend continued in 2011, as three therapies, 

CYP17 inhibitor abiraterone acetate, 1 

bone-targeting agent radium-223, 2 and 

androgen-signaling inhibitor MDV3100, 3 

were shown to prolong life in definitive 

phase III clinical trials (Figure 1), and the 

RANKL inhibitor, denosumab, was shown 

to be superior to zoledronic acid in reducing 

the morbidity associated with bone 

metastases. 4 The demonstration that agents 

targeting unique aspects of the malignant 

process associated with tumor cell growth 

and survival could provide meaningful clinical 

benefits has highlighted the importance 

of understanding the biology of castrationresistant 

prostate cancer (CRPC). The trials 

established important principles, which will 

be discussed. 

The first principle is that CRPCs are not 

hormone refractory. CRPCs acquire diverse 

mechanisms to reactivate the androgen 

receptor signaling pathway in the environment 

of castrate levels of androgens, including 

an increase in the androgen biosynthetic 

machinery and overexpression of androgen 

receptor. Thus, further decreasing androgen 

levels by inhibiting steroid synthesis 

enzymes in the adrenal glands and tumor 

may be of benefit. CYP17 is a cytochrome 

P450 enzyme that catalyzes the rate-limiting 

step of androgen synthesis; abiraterone 

acetate is a structural analog of the CYP17 

substrate pregnenolone that is rationally 

designed to be a specific and irreversible 

inhibitor of CYP17. A large international 

phase III trial (Cougar AA-301) that compared 

abiraterone acetate plus prednisone 

(to prevent mineralocorticoid excess) and 

placebo plus prednisone in patients with 

CRPC who had received docetaxel showed 

an increase in median overall survival from 

10.9 to 14.8 months (hazard ratio = 0.65; 

P



■ Abiraterone acetate and MDV3100 

prolong overall survival in patients with 

docetaxel-treated castration-resistant 

prostate cancer (CRPC) 1,3 

■ Radium-223 prolongs overall survival 

in patients with CRPC, bone pain from 

disease, and who are docetaxel-treated 

or ineligible for docetaxel treatment 2 

■ Denosumab delays skeletal-related 

events compared with zoledronic acid in 

patients with CRPC and bone disease 4 

are minimal. With this goal but without 

firm evidence, the advent of the PSA test 

led to widespread screening that has been 

accompanied by a marked increase in 

men diagnosed with localized disease 

who undergo radical prostatectomy and 

definitive radiotherapy with the associated 

morbidities. Over the past 2 years, the US 

PLCO trial showed no reduction in prostate 

cancer-specific mortality (PCSM) at 7-years 

after the initiation of PSA screening; the 

European Randomized Study of Screening 

for Prostate Cancer showed a 20% decrease 

in PCSM at 9 years after the initiation of 

PSA screening; and the Göteborg randomized 

screening trial showed a 44% decrease 

in PCSM at 14 years after the initiation of 

screening. 7–9 These results, along with an 

analysis of other early detection studies led 

the USPSTF to recommend against PSA 

screening because of “moderate or high certainty 

that the service has no net benefit or 

that the harms outweigh the bene fits.” 10 The 

recommendation triggered a firestorm of 

debate, proponents of screening highlighting 

flaws in methodology and interpretation 

and opponents the limited benefits, anxiety 

and morbidity a diagnosis produces, and the 

high societal costs. 

There is strong evidence prostatectomy 

and radiotherapy can decrease PCSM by 

approximately 50% in clinically localized 

disease. However, in low-risk disease where 

the 15-year PCSM is

in CLL. Four cases were analyzed and 46 

somatic mutations were identified. 2 Four 

genes with recurrent mutations were confirmed 

in 363 patients with CLL: NOTCH1, 

XPO1, MYD88 and KLHL6. Mutations in 

MYD88 and KLHL6 were predominantly 

found in patients with CLL who had a high 

number of somatic hypermutations in the 

variable region of IGHV, whereas mutations 

in NOTCH1 and XPO1 were mostly 

detected in patients who did not have IGHV 

mutations. These findings indicate a role 

for mutations in NOTCH1, MYD88 and 

XPO1 in the clinical evolution of CLL. 

In a similar study on 91 patients with 

CLL, Wang et al. 3 performed massively parallel 

sequencing of 88 whole exomes and 

genomes. They found nine genes that are 

mutated at significant frequencies, including 

four with established roles (TP53 in 15% 

of patients, ATM in 9%, MYD88 in 10%, and 

NOTCH1 in 4%) and five genes without 

established roles (SF3B1, ZMYM3, MAPK1, 

FBXW7, and DDX3X). SF3B1, which functions 

at the catalytic core of the spliceosome, 

was the second most frequently mutated 

gene (15% of patients). SF3B1 mutations 

occurred primarily in tumors with deletions 

in chromosome 11q, which are associated 

with a poor prognosis. The authors also 

showed that mutations in SF3B1 induced 

alterations in pre–mRNA splicing. 

All three studies have considerable clinical 

implications for CLL. Firstly, the stem 

cell origin of CLL offers a plausible explanation 

for the fact that conventional chemoimmunotherapies 

regularly fail to cure CLL. 

This type of therapy may not effectively 

eradi cate the HSC pool that regenerates CLL 

cells. Secondly, our understanding of the 

genetic basis of CLL has improved. These 

advances will facilitate the development of 

better-targeted therapies for this disease. 

In the past 10 years, a remarkable improvement 

in overall survival was achieved for 

several types of B-cell lymphomas. This 

improvement was largely a result of the use 

of rituximab, an antibody targeting CD20. 

In follicular lymphoma, several randomized 

trials have demonstrated that addition 

of rituximab to different chemotherapeutic 

regimens can prolong survival; therefore, 

rituximab-based chemoimmuno therapy is 

the current standard first-line treatment. 

Disease progression usually occurs 3–5 years 

after initial therapy and rituximab maintenance 

therapy was previously shown to have 

a clinical benefit in patients with relapsed 

disease. The PRIMA study 4 evaluated the 

benefit of rituximab maintenance therapy 

after first-line treatment for follicular lymphoma. 

In this study, 1,019 patients who 

achieved a response after different chemoimmunotherapies 

(rituximab plus cyclophosphamide, 

vincristine, doxo rubicin 

and prednisone [R-CHOP]; rituximab plus 

cyclophosphamide, vincristine and prednisone; 

or rituximab plus fludarabine, 

cyclo phosphamide and mitoxantrone) were 

randomly assigned to receive 2 years of maintenance 

therapy with rituximab (375 mg/m² 

every 8 weeks) or no further therapy (observation). 

The maintenance treatment was 

well tolerated. Infectious events were more 

common in the maintenance arm than the 

observation arm, but were mostly mild or 

moderate and only a few patients withdrew 

from the study because of toxicity. No significant 

decrease in immunoglobulin levels was 

observed and patient quality of life was not 

affected by the repeated rituximab infusions. 

Maintenance therapy improved the 

quality of response and prolonged progression-free 

survival and event-free survival. 

No effect on overall survival was shown 

for rituximab maintenance therapy, which 

might be explained by a short follow-up 

period and the efficacy of salvage therapies. 

However, rituximab should be considered as 

maintenance therapy after first-line chemoimmunotherapy 

in follicular lymphoma, as 

the duration of response to first-line therapy 

has prognostic value. 5 

The outstanding outcome observed in 

patients with Hodgkin lymphoma allowed 

researchers to consider a reduction in 

treatment intensity to reduce both acute 

and long-term adverse events, such as 

infertility and secondary neoplasias. The 


■ Genomic analyses of patients with 

chronic lymphocytic leukemia identified 

mutations in genes such as Notch1 and 

SF3B1 that have prognostic impact 2,3 

■ Rituximab maintenance therapy after 

first-line treatment with rituximab-based 

chemoimmunotherapy significantly 

improves the quality of response and 

prolongs progression-free survival in 

patients with follicular lymphoma 4 

■ In advanced-stage, high-risk Hodgkin 

lymphoma, reduction in treatment 

intensity has not improved outcome and 

further analyses are needed to define the 

optimal treatment intensity 7 

■ Patients with diffuse large B-cell 

lymphoma, in particular, those with a 

non-germinal center B-cell-like subtype, 

benefit from the addition of bortezomib 

to first-line chemoimmunotherapy 9 


HD10 trial of the German Hodgkin Study 

Group (GHSG) 6 showed that two cycles of 

ABVD (doxo rubicin, bleomycin, vinblastine 

and dacarbazine) therapy followed 

by 20 Gy of involved–field radio therapy 

was as efficacious as four cycles of ABVD 

and 30 Gy of involved-field radiotherapy 

in patients with stage I or II disease and 

favorable risk factors. Reduced treatment 

intensity may be considered as the new 

standard treatment for early-stage, lowrisk 

Hodgkin lymphoma. By contrast, the 

reduction of treatment intensity is debated 

in advanced-stage Hodgkin lymphoma 

(stage II–IV or IIB with extranodal lesions 

or mediastinal mass). 

The results of the HD12 trial by Borchmann 

et al. 7 were slightly disappointing, because 

the reduction of the intensity of chemotherapy 

from eight cycles of high-dose 

BEACOPP (bleomycin, etoposide, doxorubicin, 

cyclophosphamide, vincristine, 

procarbazine and prednisolone) to four 

cycles of high-dose BEACOPP followed 

by four cycles of BEACOPP at the baseline 

dose did not reduce the severity of toxicity or 

treatment-related mortality, but could possibly 

reduce efficacy. Thus, the GHSG considers 

eight cycles of high-dose BEACOPP 

as the standard treatment for advancedstage 

Hodgkin lymphoma and is evaluating 

other individualized, PET-controlled dose 

reduction strategies in ongoing trials. 

Viviani et al. 8 compared BEACOPP and 

ABVD in advanced-stage Hodgkin lymphoma. 

In this trial, 331 patients received 

either four cycles of high-dose BEACOPP 

plus four cycles of BEACOPP at baseline 

dose or six to eight cycles of ABVD; each 

treatment was followed by involved-field 

radiotherapy. The estimated 7-year rate of 

freedom from first progression was 85% in 

patients treated with BEACOPP and 73% 

in patients treated with ABVD. However, 

all patients with a relapse or less than complete 

response after initial therapy were 

treated with multiple cycles of ifosfamidecontaining 

chemotherapy followed by 

KEY ADVANCES IN MEDICINE JANUARY 2012 | S15 

© Eraxion | Dreamstime.com


high-dose chemo therapy with carmustine, 

etoposide, cytarabine, and melph alan 

plus autologous hemato poietic stem-cell 

support. After completion of treatment 

including the salvage therapy, the 7-year 

rate of overall survival was 89% in patients 

initially treated with BEACOPP compared 

to 84% in patients who had received ABVD. 

As this difference in overall survival was not 

significant, the authors concluded that treatment 

with BEACOPP resulted in a more 

effective disease control, but not in a better 

long-term outcome, compared with ABVD. 

They argued that while a major proportion 

of patients could be cured by the initial 

BEACOPP therapy, this clinical benefit 

might be neutralized by a high rate of longterm 

adverse events, in particular myelotoxicity, 

infections and secondary neoplasias. 

Viviani et al. 8 deduced that the BEACOPP 

regimen presents an over treatment strategy 

for a large number of patients and 

recommended ABVD for patients with 

advanced-stage or unfavorable Hodgkin 

lymphoma. This study has triggered an 

intense discussion about the need for an 

intensive BEACOPP therapy in advancedstage 

Hodgkin lymphoma, as few patients 

who relapse can be rescued with a high-dose 

salvage therapy. However, this trial 8 was not 

powered to demonstrate a survival difference 

between the two treatments and the 7-year 

overall survival differed by 5% in favor of 

the BEACOPP regimen. Moreover, median 

observation time (61 months) and the 

number of patients were low. As a result, an 

appropriate treatment intensity in advancedstage 

or unfavorable Hodgkin lymphoma is 

still debated. 

The improvements in our understanding of 

the molecular pathogenesis of non-Hodgkin 

lymphoma have led to the develop ment of 

novel therapeutic agents that interfere with 

signaling pathways involved in lymphomagenesis. 

For instance, the addition of the 

proteasome inhibitor bortezomib enhanced 

the activity of chemo immunotherapy with 

R-CHOP as first-line treatment for diffuse 

large B-cell lymphoma (DLBCL) and mantle- 

cell lymphoma. 9 Ruan et al. 9 demon strated 

that, in particular, patients with a nongerminal 

center B-cell-like (GCB) subtype, 

which is usually associ ated with a worse 

outcome, benefit from the addition of bortezomib. 

This increased clinical benefit can 

be explained by the fact that the non-GCB 

subtype is characterized by a deletion in a 

tumor-suppressor gene that activates NF-κB 

and this activation is blocked by bortezomib. 

Thus, a worse prognosis in this subgroup of 

patients with DLBCL could be overcome by 

bortezomib treatment. 

Overall, 2011 saw exciting developments 

in the understanding and treatment of B-cell 

lymphomas. Whereas research in Hodgkin 

lymphoma aims to reduce the adverse effects 

of first-line treatment, in most other lymphomas 

more-effective therapies are needed. 

The growing understanding of the pathogenesis 

of these lymphomas will facilitate 

the develop ment of novel therapeutic agents. 

Department of Internal Medicine I and Center 

for Integrated Oncology Köln-Bonn, University of 

Cologne, Joseph-Stelzmann-Straße. 9, 50924 

Cologne, Germany (P. Cramer, M. Hallek). 

Correspondence to: M. Hallek 

michael.hallek@uni-koeln.de 


M. Hallek declares associations with the following 

companies: Celgene, Mundipharma, Roche. See the 

article online for full details of the relationships. 

P. Cramer declares no competing interests. 

1. Kikushige, Y. et al. Self-renewing hematopoietic 

stem cell is the primary target in pathogenesis 

of human chronic lymphocytic leukemia. Cancer 

Cell 20, 246–259 (2011). 

2. Puente, X. S. et al. Whole-genome sequencing 

identifies recurrent mutations in chronic 

lymphocytic leukaemia. Nature 475, 101–105 

(2011). 

3. Wang, L. et al. SF3B1 and other novel cancer 

genes in chronic lymphocytic leukemia. N. Engl. 

J. Med. http://dx.doi.org/10.1056/ 


4. Salles, G. et al. Rituximab maintenance for 

2 years in patients with high tumor burden 

follicular lymphoma responding to rituximab 

plus chemotherapy (PRIMA): a phase 3, 

randomised controlled trial. Lancet 377, 42–51 

(2011). 

5. Bachy, E. et al. Long-term follow-up of patients 

with newly diagnosed follicular lymphoma in the 

prerituximab era: effect of response quality on 

survival - a study from the Groupe d’Etude des 

Lymphomes de l’Adulte. J. Clin. Oncol. 28, 

822–829 (2010). 

6. Engert, A. et al. Reduced treatment intensity in 

patients with early-stage Hodgkin’s lymphoma 

N. Engl. J. Med. 363, 640–652 (2010). 

7. Borchmann, P. et al. Eight cycles of escalateddose 

BEACOPP compared with four cycles of 

escalated-dose BEACOPP followed by four 

cycles of baseline-dose BEACOPP with or 

without radiotherapy in patients with advancedstage 

Hodgkin’s lymphoma: final analysis of 

the HD12 trial of the German Hodgkin Study 

Group. J. Clin. Oncol. 29, 4234–4242 (2011). 

8. Viviani, S. et al. ABVD versus BEACOPP for 

Hodgkin’s lymphoma when high-dose salvage 

is planned. N. Engl. J. Med. 365, 203–212 

(2011). 

9. Ruan, J. et al. Bortezomib plus CHOP-rituximab 

for previously untreated diffuse large B-cell 

lymphoma and mantle cell lymphoma. J. Clin. 

Oncol. 29, 690–697 (2011). 

MELANOMA IN 2011 

A new paradigm tumor for drug 

development 

Alexander M. M. Eggermont and Caroline Robert 

Melanoma has emerged as the paradigm tumor for drug development 

through mutation-targeted therapies (inhibitors targeting BRAF, MEK, and 

c-KIT) and immunotherapy. Exploring the combinations of both approaches 

is a challenge that will require scientific rationale and the cooperation of 

the pharmaceutical industry. But, with these challenges comes another 

opportunity to change the paradigms in drug development. 

Eggermont, A. M. M. & Robert, C. Nat. Rev. Clin. Oncol. 9, 74–76 (2012); published online 10 January 2012; 


For the past 40 years no treatments developed 

for melanoma have significantly 

improved survival over dacarbazine, a drug 

with a response rate of around 10%. In the 

past decade, we have witnessed—in the fields 

of mutation-driven drug development and 

immuno modulation—the establishment of 

treatments actively impacting survival. This 

is just the beginning of a promising journey 

to develop rational and biology-driven treatments 

for patients with melanoma with clinically 

significant impact to greatly change the 

thera peutic landscape. 

The treatment of melanoma has evolved 

from using non-selective inhibitors to more 

selective agents, with BRAF, MEK and c-KIT 

inhibitors leading the field. BRAF mutations 

are the most frequently occurring and most 

important mutations that provide drugable 

targets in melanoma. The first selective 

BRAF inhibitor developed in the clinical 

setting was vemurafenib. 1 In a randomized 

phase III trial published in 2011, this 

drug led to major tumor responses in 50% 

of patients, and minor responses in >30% of 

patients. 2 The most common adverse events 

were arthralgia, fatigue, and cutaneous 

mani festations such as rash, photo sensitivity, 

pruritis, and squamous-cell carcinoma of 

the keratoacanthoma-type in around 20% 


of patients. 1,2 The phase III BRIM-3 trial, 

in which vemurafenib was compared with 

dacarbazine in treatment-naive patients, 

showed an improvement in progressionfree 

survival (PFS) of 5.3 months for vemurafenib. 

The impact on overall survival has 

not yet been established and is probably 

similar because, as the trial was unblinded at 

the first interim analysis and cross over was 

allowed, changes in overall survival will be 

somewhat compromised by this cross over. 

Responses to vemurafenib are immediate 

and evident on PET scans within 

1–2 weeks after treatment commencement. 

Disappointing, however, is the short median 

duration of these responses, and essentially 

all patients relapse, 50% in the first 

5–6 months, 50% any time after 6 months. 

Various mechanisms of drug resistance have 

been described, mostly reflecting primary 

resistance (present from the beginning) and 

heterogeneity of the tumors. 

As BRAF inhibition leads to reactivation 

of the MAPK pathway and enhances cell 

growth through CRAF, combining a BRAF 

inhibitor with a MEK inhibitor may both 

prolong PFS and prevent the appearance 

of squamous-cell carcinomas. The report 

in 2011 of the use of a BRAF inhibitor 

(GSK436) combined with a MEK inhibitor 

(GSK212), clearly indicate these beneficial 

effects. 3 NRAS mutations occur in about 

20% of melanomas but RAS remains a rather 

elusive target in cancer, with no available 

drugs that can directly antagonize its signaling 

activity. Dual targeting of the MAPK and 

PI3K pathways might abrogate the effect of 

NRAS mutation (Figure 1). 

Mutations in c-KIT are also important in 

melanoma, especially in mucosal and acral 

melanomas, in which mutations in c-KIT 

are found in 20–30% of the cases. These 

types of melanoma represent less than 20% 

of all melanomas in the white population 

in the Western world, but incidence in the 


■ BRAF and MEK inhibitors are key agents 

in treating BRAF-mutated melanomas, 

and their combination is essential to 

optimize results 2,3 

■ Immunomodulators, such as antibodies 

blocking CTLA-4 and PD-1, establish 

immunotherapy as a key component of 

anti-tumor strategies, required for 

long-term responses and potential cure 6 

■ Ulcerated primary melanoma is a distinct 

biologic entity that indicates sensitivity 

to adjuvant IFN therapy determining when 

such treatment should be indicated 10 

Asian population is >70%. 4 Response rates 

and PFS rates with imatinib are in the range 

of 15–20%, which is rather disappointing 

compared to the activity of this inhibitor in 

GIST tumors, and a reflection of a different 

pattern of mutations. 4 These mutations make 

melanoma a tumor that often presents with 

multiple perturbed pathways and with many 

routes to escape from single or multiple drug 

exposure. Therefore, although combinations 

of drugs targeting two proteins in the same 

signaling pathway or in different pathways 

are currently being explored, it will be critical 

to combine targeted drugs with drugs 

that modulate the immune system. 

The cytotoxic T-lymphocyte–associated 

antigen 4 (CTLA-4) ligand is a negative 

regulator of T cells; therefore, blocking 

CTLA-4 action augments T-cell activation 

and proliferation, and inhibits immune 

system tolerance. The anti-CTLA-4 monoclonal 

antibody ipilimumab has recently 

been assessed in randomized phase III 

trials. Improved overall survival (4 months) 

was demonstrated for ipilimumab alone 

or in combination with the gp100 peptide 

vaccine compared with the vaccine alone in 

patients who did not respond to prior treatment. 

5 Improved overall survival was also 

demonstrated for ipilimumab in the firstline 

setting when combined with dacarbazine 

(2.1 months). 6 Thus, in 2011, the FDA 

approved ipilimumab for advanced melanoma 

at a dose of 3 mg/kg, administered 

every 3 weeks for a total of four doses for 

all patients with advanced melanoma in 

the first-line and second-line and settings. 

In the pivotal trial assessing the combination 

of dacarbazine with ipilimumab as 

first-line treatment at a dose of 10 mg/kg, a 

high percentage of liver enzyme alterations 

was observed. 6 This adverse effect resulted 

in significant percentage of patients abandoning 

the treatment, which is believed to 

have reduced the impact of ipilimumab. 

Because ipilimumab reactivates immune 

responses that have been silenced, there is 

a risk that it may reactivate lingering subclinical 

auto immune responses in certain 

patients, resulting in immune-related 

adverse events. Some of the most prominent 

were colitis, dermatitis, and hypo physitis, 

all of which must be closely monitored as 

patients may need the immediate use of 

corticosteroids. Ipilimumab has a modest 

response rate of around 10%, but responses 

are almost always durable with a median 

of 20 months. Moreover, there was a clear 

separation of the survival curves in both 

trials, indicating durable responses that last 


PI3K pathway 

Inhibition 

Figure 1 | Dual targeting of the MAPK and 

PI3K pathways in melanoma treatment. This 

figure illustrates how combining inhibition of 

BRAF and MEK (intra-pathway combined 

blocking) with AKT (inter-pathway 

combined blocking) might abrogate the effect 

of NRAS mutation. 

for >3 years—with a significant number 

of patients that have not relapsed after 

5 years—which may indicate potential cure. 

A reason why patients might have stopped 

taking the treatment is that it takes time for 

the responses to ipilimumab to develop. 

Responses may even be preceded by progression 

of disease at 6 or 8 weeks, which 

might reflect lymphocyte infiltration of the 

lesions that will subsequently regress. These 

observations have led to the development of 

novel, immune-related response criteria that 

might more accurately describe response 

to immunotherapy and avoid premature 

treatment cessation in patients with disease 

progression before response. 7 

Studies that combine BRAF inhibitors 

with cytokines such as IFN, IL2, GM-CSF 

and anti-angiogenic agents are currently 

under clinical development. Although early 

reports indicate improved response rates 

to these combinations, the interactions 

between these drugs are poorly understood, 

and in the absence of clear biomarkers 

to provide rational guidance as to which 

combinations should be used and how, 

serious efforts should be made in this area 

to allow for rational plans and progress. 

Green et al. 8 have proposed that various 

chemotherapeutics may exert their action 

through immunogenic cell death (leading 

to antigen presentation and stimulating the 

immune system) or tolerogenic cell death 

(necrosis without immune-system priming 

but instead leading to immuno logical tolerance). 

9 This approach could provide rational 

guidance to explore combination treatments. 


PI3K 

AKT 

mTOR 

RAS 

CRAF 

RTK 

MAPK pathway 

BRAF 

MEK 

ERK 

Cell growth, proliferation, survival 

GSK436 

GSK212


New immunomodulators are being tested 

in early-phase studies. Most promising are 

the results seen with the monoclonal antibody 

that acts against the programmed 

death-1 receptor (PD-1R), the ligand of 

which (PD-1L) can be expressed directly 

on melanoma cells. Good responses have 

been observed in phase I studies with possibly 

fewer accompanying immune-related 

adverse events than observed with ipilimumab 

treatment. 9 Another immunomodulator, 

pegylated IFN-α-2b, was 

approved in 2011 by the FDA as adjuvant 

therapy for patients with stage III lymphnode 

positive disease after lymph-node 

dissection, on the basis of a significant 

improvement of relapse-free survival (RFS). 10 

This EORTC 18991 trial (n = 1,256 patients) 

had been preceded by the EORTC 18952 

trial, which evaluated intermediate doses 

of regular IFN-α-2b in 1,388 patients. 10 In 

both trials, patients were stratified according 

to nodal status and presence or absence 

of ulceration in the primary tumor. In both 

trials, low tumor-stage and the presence 

of ulceration significantly correlated with 

improved outcome in the IFN-treatment 

arms, as reported by the recently published 

meta-analysis of these trials. 10 In patients with 

an ulcerated primary tumor and stage IIB or 

limited stage III disease (positive sentinel 

node) there was a highly significant reduction 

(30–40%) of the relative risk of RFS, distant 

metastasis-free survival and overall survival. 

In patients with stage III–N2 disease, these 

benefits were progressively lost. This finding 

strongly indicates that ulcerated melanoma 

represents a distinct biologic entity that will 

be assesed in the EORTC 18081 trial, which 

will evaluate pegylated-IFN-α-2b versus 

observation in node-negative patients with 

ulcerated primary melanomas. Adjuvant 

treatment with ipilimumab in patients with 

advanced stage IIIb/IIIc is under evaluation 

in the EORTC 18071 trial that has now 

completed patient accrual. 

There has never been a more exciting and 

dynamic time in the treatment of melanoma. 

To explore all potential combinations is 

impossible. Thus, we need to stick to a rational 

approach—guided by principles such as 

immunogenic cell death—and translational 

research programs to identify biomarkers 

predictive for outcomes of both the immunotherapeutic 

and the mutation-driven drug 

development approach. Without such an 

approach we could revert to the empiric ways 

that characterized clinical drug development 

of the past, and that is no longer acceptable 

in the 21 st century. 

Institut de Cancérologie Gustave Roussy, 114 

Rue Edouard Vaillant, 94805 Villejuif, Paris- 

Sud, France (A. M. M. Eggermont, C. Robert) 

Correspondence to: A. M. M. Eggermont 

alexander.eggermont@igr.fr 


The authors declare associations with the following 

companies: Bristol-Myers Squibb, GlaxoSmithKline, 

Merck, Roche. See the article online for full details 

of the relationships. 

1. Flaherty, K. T. et al. Inhibition of mutated, 

activated BRAF in metastatic melanoma. 

N. Engl. J. Med. 363, 809–819 (2010). 

2. Chapman, P. B. et al. Improved survival with 

vemurafenib in melanoma with BRAF V600E 

mutation. N. Engl. J. Med. 364, 2507–2516 

(2011). 

3. Infante, J. R. et al. Phase I/II study to assess 

safety, pharmacokinetics, and efficacy of the 

oral MEK 1/2 inhibitor GSK1120212 

(GSK212) dosed in combination with the oral 

BRAF inhibitor GSK2118436 (GSK436) 

[abstract]. J. Clin. Oncol. 29 (Suppl.), 

CRA8503J (2011). 

4. Carvajal, R. D. et al. KIT as a therapeutic target 

in metastatic melanoma. JAMA. 305, 

2327–2334 (2011). 

5. Hodi, F. S. et al. Improved survival with 

ipilimumab in patients with metastatic 

melanoma. N. Engl. J. Med. 363, 711–723 

(2010). 

6. Robert, C. et al. Ipilimumab plus dacarbazine 

for previously untreated metastatic melanoma. 

N. Engl. J. Med. 364, 2517–2526 (2011). 

7. Hoos, A. et al. Improved endpoints for cancer 

immunotherapy trials. J. Natl Cancer Inst. 102, 

1388–1397 (2010). 

8. Green, D. R., Ferguson, T., Zitvogel, L. & 

Kroemer, G. Immunogenic and tolerogenic cell 

death. Nat. Rev. Immunol. 9, 353–363 (2009). 

9. Brahmer, J. R. et al. Phase I study of single-agent 

anti-programmed death-1 (MDX-1106) in 

refractory solid tumors: safety, clinical activity, 

pharmacodynamics, and immunologic correlates. 

J. Clin. Oncol. 28, 3167–3175 (2010). 

10. Eggermont, A. M. et al. Ulceration and stage are 

predictive of interferon efficacy in melanoma: 

results of the phase III adjuvant trials EORTC 

18952 and EORTC 18991. Eur. J. Cancer. 

doi:10.1016/j.ejca.2011.09.028 

BONE CANCER IN 2011 

Prevention and treatment of bone 

metastases 

Robert E. Coleman 

Bone-targeting treatments have transformed the quality of life of patients 

with metastatic bone disease. 2011 saw the emergence of denosumab—a 

RANK ligand-specific antibody—as a more-effective alternative treatment 

to bisphosphonates and of data on the use of bone-targeting treatments to 

prevent metastasis from breast and prostate cancers. 

Coleman, R. E. Nat. Rev. Clin. Oncol. 9, 76–78 (2012); published online 20 December 2011; 


Bone disease accounts for substantial morbidity 

and mortality in patients with cancer. 

Advanced-stage solid tumors, notably 

those arising from the breast and prostate, 

and multiple myeloma are associated with 

a heavy burden of skeletal disease, with 

potentially debilitating or life-limiting skeletal-related 

events (SREs). As a result, bonetargeting 

treatments have been introduced 

alongside specific anticancer treatments 

to minimize skeletal morbidity and preserve 

the patients’ quality of life and physical 

function. An increased understanding 

of the interplay among the disseminated 

tumor cells, the bone marrow and both hostderived 

and tumor-derived growth factors 

has shown that the complex interactions in 

the bone marrow micro environment provide 

candidate therapeutic targets. Modification 

of these inter actions is emerging as an 

important anticancer treatment strategy and, 

in 2011, considerable developments have 


■ Denosumab provides a more effective, 

convenient and well-tolerated alternative 

treatment to zoledronic acid for the 

prevention of skeletal morbidity 2,3 

■ The adjuvant use of zoledronic acid in 

early-stage breast cancer should be 

restricted to postmenopausal women, as 

women with residual ovarian function do 

not benefit from this treatment 7 

■ Denosumab delays the development 

of bone metastases in men with 

castration-resistant prostate cancer 10 

occurred in the treatment and prevention of 

bone metastases. 

In the past 20 years, bisphosphonates have 

been the choice of treatment for preventing 

skeletal morbidity associated with malignant 

bone disease. However, recognition of 

the importance of the receptor activator of 

nuclear factor κ-B ligand (RANKL) in bone 


metastasis has provided a new specific therapeutic 

target. Denosumab is a fully human, 

synthetic IgG 2 antibody that is administered 

via subcutaneous injection and binds 

with high affinity to RANKL, preventing 

the interaction of RANKL and RANK and 

inhibiting osteoclast function. 

In 2011, denosumab became available for 

clinical use after the publication of three 

large randomized double-blind registration 

studies. These trials included 5,723 patients 

with bone metastases secondary to breast 

cancer (n = 2,046), 1 castration-resistant 

prostate cancer (n = 1,901) 2 and other 

advanced-stage solid tumors including 

non-small-cell lung cancer (n = 702), other 

types of solid tumors (n = 894) and myeloma 

(n = 180). 3 In these studies, patients were 

randomly assigned to receive denosumab 

or zoledronic acid every 3–4 weeks, plus 

calcium and vitamin D supplements. The 

primary end point was time to first onstudy 

SRE. Stopeck and colleagues 1 showed 

that denosumab was statistically superior 

to zoledronic acid in delaying the first SRE 

in patients with bone meta stasis secondary 

to breast cancer; the median time to first 

on-study SRE was 26.4 months in the zoledronic 

acid-treated group and has not been 

reached in the denosumab-treated group. 

Similarly, Fizazi and colleagues 2 reported 

that denosumab was superior to zoledronic 

acid in delaying the first SRE in patients 

with bone meta stasis secondary to prostate 

cancer; the median time to first on-study 

SRE was 17.1 months in the zoledronic 

acid-treated group and 20.7 months in the 

denosumab-treated group. 

In patients with bone metastasis secondary 

to advanced solid tumors and myeloma, 

Henry and colleagues 3 showed that denosumab 

was not inferior to zoledronic acid in 

delaying the first SRE, but was not superior 

either. In an analysis of multiple events of 

SREs, denosumab was superior to zoledronic 

acid in patients with breast cancer 1 

and prostate cancer 2 (Table 1). In all three 

studies, denosumab was well tolerated, 

and a key difference in the safety profiles 

of denosumab and zoledronic acid was the 

lack of an effect on kidney function with 

denosumab, which obviates the need for 

monitoring renal function that is mandated 

when treating patients with intravenous 

bisphosphonates. Similar to the use of intravenous 

bisphosphonates used in oncology 

settings, osteonecrosis of the jaw (ONJ) was 

the most important adverse event associated 

with denosumab, but it was uncommon. 

The cumulative incidence rates of ONJ were 

similar for both treatments: 0.5% and 0.8% 

in year 1, 1% and 1.8% in year 2, and 1.3% 

and 1.8% in year 3 for zoledronic acid and 

denosumab, respectively. 4 

The use of denosumab in patients with 

advanced-stage cancer is likely to be 

influenced by cost, in particular, because 

denosumab did not improve either progression-free 

survival or overall survival 

compared with zoledronic acid. However, 

collectively these trials show that denosumab 

is slightly more effective and convenient 

to administer, has some advantages in 

terms of safety over the current gold standard 

of treatment and represents an important 

advancement in the quality of life of 

patients with advanced-stage cancer. 

Other agents targeting the bone metastasis 

pathway are in development. The 

most interesting novel strategy for bone 

metastasis treatment during 2011 was 

reported by Parker and colleagues. 5 In 

this study, 922 men with advanced-stage 

castration-resistant prostate cancer who had 

not responded or were considered unsuitable 

for chemotherapy were randomly 

assigned (2:1) to receive a bone-localizing 

α-particle-emitting agent, 223 RaCl 2 (also 

called alpharadin) or placebo. Median 

overall survival increased from 11.2 months 

to 14 months in patients receiving alpharadin 

(hazard ratio [HR] 0.695; 95% CI 

0.552–0.875, P = 0.002). 5 In addition to the 

effects of bone-targeting treatments on the 

risk of skeletal complications in patients 

with cancer, these agents could modify the 

course of the disease via inhibitory effects 

on the ‘vicious cycle’ of growth factor 

and cytokine signaling between tumor 

and bone cells within the bone marrow 

microenvironment. 

In patients with early-stage breast 

cancer, inconsistent effects on disease outcomes 

were previously reported in clinical 

trials of adjuvant bisphosphonate treatment. 

However, in 2009, the results of the 


Table 1 | Phase III registration trials of denosumab in advanced-stage cancer 

Disease setting End point Hazard ratio 95% CI P (relative to ZA) 

Breast cancer 1 Time to 1 st SRE 

Time to 1 st and subsequent SRE 

CRPC 2 Time to 1 st SRE 


OST and MM 3 Time to 1 st SRE 


Total 4 Time to 1 st SRE 


ABCSG-12 trial 6 stimulated a considerable 

amount of interest in the field of targeting 

bone micro environment to modify 

the course of early-stage breast cancer. 

Zoledronic acid treatment every 6 months 

for 3 years significantly improved diseasefree 

survival (DFS) in premenopausal 

women with endocrine-sensitive earlystage 

breast cancer previously treated with 

ovarian suppression therapy (goserelin) 

and tamoxi fen or anastrozole. 6 In 2011, the 

updated results of this trial 7,8 showed that 

DFS was still improved with adjuvant zoledronic 

acid treatment and overall survival 

was also increased. Notably, these beneficial 

effects of zoledronic acid were only 

seen in patients over 40 years of age; goserelin 

treatment induced post menopausal 

levels of circulating reproductive hormones 

consistently in these patients. 

Improvements in DFS and overall survival 

was also reported in postmenopausal 

women in the AZURE trial, a large randomized 

adjuvant trial that was designed 

to determine whether treatment with zoledronic 

acid in addition to adjuvant therapy 

improved disease outcomes in most women 

with early-stage breast cancer. 9 In this study, 

3,360 patients were randomly assigned 

to receive standard adjuvant systemic 

therapy with or without zoledronic acid 

every 3–4 weeks for six doses, then every 

3–6 months thereafter, for a total of 5 years. 9 

After a median follow-up of 59 months, no 

significant difference was seen in DFS or 

overall survival. However, in a prespecified 

subgroup analysis, a significant increase 

in DFS was detected with zoledronic acid in 

1,041 postmenopausal women (who were 

postmenopausal for >5 years at the time of 

diagnosis): 5-year invasive DFS was 71% in 

the control arm and 78.2% in those treated 

with zoledronic acid (adjusted HR 0.75; 

95% CI 0.59–0.96, P = 0.02). 9 In addition, 

zoledronic acid improved overall survival 

in this group of women, with 5-year overall 


0.82 

0.77 

0.82 

0.82 

0.84 

0.90 

0.83 

0.82 

0.71–0.95 

0.66–0.89 

0.71–0.95 

0.71–0.94 

0.71–0.98 

0.77–1.04 

0.76–0.90 

0.77–1.04 

P = 0.01 

P = 0.001 

P = 0.008 

P = 0.008 

P = 0.03 

P = 0.14 

P


survival rates of 79% in the control group 

and 85% in patients treated with zoledronic 

acid (adjusted HR 0.74; 95% CI 0.55–0.98, 

P = 0.04). The data from both ABCSG-12 

and AZURE 6,9 trials suggest that the beneficial 

effects of adjuvant zoledronic acid 

treatment are dependent on an environment 

with low reproductive hormone levels. The 

mechanisms underlying this observation 

are under investigation. 

Prostate cancer has the propensity to 

metastasize almost exclusively to the bone 

and, therefore, provides the ideal clinical 

setting for the evaluation of bone-targeting 

treatments to modify the disease course. In a 

study by Smith and colleagues, 10 1,432 men 

with non-metastatic castration-resistant 

prostate cancer at high risk for bone metastasis 

(determined by either a PSA level 

≥8.0 ng/ml and/or PSA doub ling time of 

≤10 months) were randomly assigned to 

receive a monthly treatment of denosumab 

(120 mg) or placebo. Bone metastasis-free 

survival was significantly increased with 

denosumab by a median of 4.2 months (HR 

0.85; 95%CI 0.73–0.98, P = 0.028), and the 

onset of first symptomatic bone metastases 

was delayed. This effect, however, did not 

translate into any improvement in overall 

survival, and as the cumulative incidence of 

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ONJ was high (4% after 3 years), whether 

the efficacy of denosumab to reduce bone 

meta stasis is sufficient to change clinical 

practice is unclear. 

Overall, 2011 saw important developments 

in the prevention and management 

of bone metastasis. Integrating the current 

bone-targeting treatments in routine clinical 

practice and achieving a better understanding 

of the cellular processes involved 

in bone metastasis are the challenges for 

the future. 

Sheffield Cancer Research Center, Academic 

Unit of Clinical Oncology, Weston Park Hospital, 

Whitham Road, Sheffield S10 2SJ, UK. 

r.e.coleman@sheffield.ac.uk 



companies: Amgen and Novartis. See the article 

online for full details of the relationships. 

1. Stopeck, A. T. et al. Denosumab compared with 

zoledronic acid for the treatment of bone 

metastases in patients with advanced breast 

cancer: a randomized, double-blind study. 

J. Clin. Oncol. 28, 5132–5139 (2010). 

2. Fizazi, K. et al. Denosumab versus zoledronic 

acid for treatment of bone metastases in men 

with castration-resistant prostate cancer: a 

randomised, double-blind study. Lancet 377, 

813–822 (2011). 

3. Henry, D. H. et al. Randomized, double-blind 

study of denosumab versus zoledronic acid in 

the treatment of bone metastases in patients 

with advanced cancer (excluding breast and 

prostate cancer) or multiple myeloma. J. Clin. 

Oncol. 29, 1125–1132 (2011). 

4. Saad, F. et al. Incidence, risk factors, and 

outcomes of osteonecrosis of the jaw: 

integrated analysis from three blinded activecontrolled 

phase III trials in cancer patients 

with bone metastases. Ann. Oncol. http:// 

dx.doi.org/10.1093/annonc/mdr435. 

5. Parker, C. et al. Overall survival benefit of 

radium-223 chloride (alpharadin) in the 

treatment of patients with symptomatic bone 

metastases in castration-resistant prostate 

cancer (CRPC): a phase III randomised trial 

(ALSYMPCA) [abstract]. Eur. J. Cancer 

47 (Suppl. 2), a3 (2011). 

6. Gnant, M. et al. Endocrine therapy plus 

zoledronic acid in premenopausal breast 

cancer. N. Engl. J. Med. 360, 679–691 (2009). 

7. Gnant, M. et al. Adjuvant endocrine therapy 

plus zoledronic acid in premenopausal women 

with early-stage breast cancer: 62-month 

follow-up from the ABCSG-12 randomised trial. 

Lancet Oncol. 12, 631–641 (2011). 

8. Gnant, M. et al. Overall survival with adjuvant 

zoledronic acid in patients with premenopausal 

breast cancer with complete endocrine 

blockade: Long-term results from ABCSG-12 

[abstract]. J. Clin. Oncol. 29 (Suppl. 15), a520 

(2011). 

9. Coleman, R. E. et al. Breast-cancer adjuvant 

therapy with and without zoledronic acid. 

N. Engl. J. Med. 365, 1396–1405 (2011). 

10. Smith, M. R. et al. Denosumab and bone 

metastasis-free survival in men with castrationresistant 

prostate cancer: results of a global 

phase 3, randomised, placebo-controlled trial. 

Lancet http://dx.doi.org/10.1016/ 

S0140-6736(11)61226-9. 


ENDOCRINOLOGY 

THYROID DISEASE IN PREGNANCY IN 2011 

Thyroid function—effects on mother 

and baby unraveled 

Anthony P. Weetman 

The complex relationship between pregnancy and thyroid function, and its clinical effect on mother and baby, 

continued to stimulate research in 2011. Key advances were made on three important issues: how long 

maternal thyroid function affects fetal thyroid hormone levels; whether thyroid autoimmunity affects pregnancy 

outcome; and the prevalence of permanent hypothyroidism after postpartum thyroiditis. 

Weetman, A. P. Nat. Rev. Endocrinol. 8, 69–70 (2012); published online 6 December 2011; doi:10.1038/nrendo.2011.217 

The fetal thyroid gland starts to develop at 

12 weeks of gestation, and for the first half of 

pregnancy, transplacental passage of maternal 

thyroid hormone is essential for normal 

fetal development. Failure to deliver sufficient 

thyroid hormone to the fetus causes impaired 

neurological development, although whether 

other elements of fetal development are also 

affected remains unclear. The essentially 

normal outcome in neonates with congenital 

hypothyroidism promptly treated with levothyroxine 

after birth suggests that maternal 

thyroid hormones also have a fetal role in the 

second half of pregnancy. 

In a prospective survey of 886 pregnant 

Dutch women published in 2011, neonates 

born to mothers who had high-normal TSH 

levels (above the 97.5 th percentile) one or 

more times during pregnancy had lower 

total T 4 levels when routine screening was 

performed for congenital hypothyroidism 

than neonates born to mothers whose TSH 

levels had remained below the 97.5 th percentile. 

1 This result contrasts with that of a 

previous study that showed no relationship 

between maternal and neonatal thyroid function, 

2 a difference possibly related to the use 

of pregnancy-specific refer ence ranges for 

TSH measurement in the 2011 study. 

Although the women with high-normal 

TSH levels had normal free T 4 levels, the TSH 

levels might reflect a resetting of the 

pituitary–thyroid axis, which resulted in 

less T 4 being available to cross the placenta. 

Alternatively, an unsuspected increase in 

placental deiodinase activity might have 

been responsible for low T 4 availability to 

the fetus. Low gestational age was associated 

with low neonatal thyroxine levels in 

this and previous studies, which raises the 

possibility that maternal thyroid function 

throughout pregnancy, rather than just the 

first trimester, is an important determinant 

of gestational outcome. Detailed sampling of 

maternal thyroid function is required to 

investigate this hypo thesis further. 

In a related study from 2011, maternal thyroid 

function variables measured at 28 weeks 

gestation were compared with those measured 

in the umbilical cord at birth in 616 

preg nancies in the UK. 3 Maternal free T 4 and 

cord free T 4 values showed a positive correlation, 

and maternal TSH levels were inversely 

corre lated with cord free T 4 levels. This evidence 

by Shields and co-investigators is consistent 

with that of the Dutch study 1 and 

sug gests that maternal thyroid function has 

a measurable effect on fetal thyroid hormone 

levels throughout pregnancy. 

Shields et al. also examined the effect of 

thyroid hormone levels on various parameters 

of fetal growth. Cord free T 4 levels 

were associated with birth weight, length and 

skin-fold thickness. These results imply that 

fetal thyroid hormone levels have an important 

role in regulating fetal growth, especially 

when taken in conjunction with the results 

of animal experiments. 4 An unexplained 

finding was that birth weight was negatively 

associated with maternal free T 4 levels, given 

that maternal and cord free T 4 levels were 

positively associated. 

Together, these two studies highlight the 

intricacy of the maternal–fetal relationship 

with regard to thyroid function and its clinically 

important effects on fetal growth and 

ges tational age. Studies with detailed assessment 

of maternal thyroid function throughout 

the third trimester that incorpo rate 

assess ment of placental deiodinase activity 

are needed. Variable iodine intake is also a 

con founding factor that needs addressing, 

given the surprising discovery in 2011 of 

inade quate dietary supplies in the UK and 

in other countries. 5 

Multiple studies have shown that euthyroid 

pregnant woman with positive thyroid peroxidase 

(TPO) antibodies have an increased 

risk of spontaneous mis carriage and possibly 

preterm delivery. Two mechanisms might be 

responsible. Firstly, even though ‘euthyroid’, 

these women may have subtle impairment 

of thyroid function, and the effects of maternal 

thyroid function on the fetus, as discussed 

above, are responsible. Secondly, thyroid 

auto immunity dis torts the immunological 

balance required to maintain tolerance to 

the fetal semi-allograft. 6 

In 2011, a study of 245 TPO-antibodypositive 

women with TSH levels

ENDOCRINOLOGY 

in pregnancies of women who were negative 

for TPO antibodies. 7 No association 

with TPO-antibody positivity was observed 

for 12 other adverse outcomes, including 

preterm delivery between 34–37 weeks. 

Although corrected for multiple comparisons, 

the statistical tests applied were onetailed 

rather than two-tailed. Given that the 

association with respiratory distress is novel, 

this finding could be a type 1 statis tical error. 

The key feature of this study was that all the 

par ticipants were chosen to have low-normal 

TSH levels, and thus the results appear to 

show that autoimmunity per se is responsible 

for these adverse out comes. How ever, 

miscarriage rates, pre viously shown to be 

increased in TPO-antibody-positive women, 

were not specifically increased and although 

below 2.5 mU/l, TSH levels were significantly 

higher in the TPO-antibody-positive women 

than in control women. Although the results 

clearly show that a trial of levothyroxine 

during pregnancy is warranted in this subset 

of TPO-antibody-positive women with lownormal 

TSH levels, the pathogenic mechanism 

behind the adverse outcomes of such 

pregnancies is still in question. 

Postpartum thyroiditis is a transient flaring 

of pre-existing autoimmune thyroidi tis in 

the year after delivery, which seems to be a 

consequence of the restoration of nor mal 

immune function after a period of altered 

immuno regulation during pregnancy. 6 

Tran sient abnormalities of thyroid dysfunction 

are common in postpartum thyroiditis; 

however, as has been clear for over two 

decades, 2–21% of such patients have permanent 

hypo thyroidism at the end of the year 

after delivery, and this figure rises during 

follow-up over subsequent years. A survey of 

4,394 women from Southern Italy reported 

in 2011 that 3.9% had postpartum thyroiditis 

and 54% of these were hypo thyroid at 1 year 

after delivery. 8 This figure for the prevalence 

of post partum thyroiditis is rather low 

compared with that in many other studies, a 

difference that could be related to the exclusion 

of women with any thyroid dysfunction 

during the first trimester of pregnancy in the 

2011 study. In addition, the women in this 

Italian study were only screened twice postpartum, 

so some cases of dysfunction might 

have been missed. By contrast, the figure for 

the prevalence of hypothyroidism at 1 year 

is strikingly high. This finding might also be 

related to the study design—if women with 

milder forms of postpartum thyroiditis were 

excluded because of limited sampling, this 

exclusion could have distorted the overall 

prevalence results, given that such women are 


■ Maternal thyroid function has a 

measurable effect on fetal thyroid 

hormone levels throughout pregnancy 1,3 

■ Fetal thyroid hormone levels have an 

important role in regulating fetal growth, 

as measured by birth weight, length and 

skin-fold thickness 3 

■ Very preterm delivery (

gene that encodes steroid 11β-hydroxylase 

and is regulated by adrenocorticotropic 

hor mone (ACTH)—and coding sequences 

from CYP11B2—a gene that encodes aldosterone 

synthase and is primarily regulated 

by angiotensin II. Expression of this hybrid 

gene leads to ACTH-regulated aldo sterone 

overproduction. 2 Glucocorticoids, in small 

doses, suppress hybrid gene expression 

and ameliorate primary aldosteronism and 

hypertension. Because wild-type CYP11B1 

is expressed in the zona fasciculata (ZF) 

of the adrenal cortex, so is the hybrid gene 

(Figure 1). Thus, aberrant aldosterone synthase 

activity, normally restricted to the 

zona glomerulosa (ZG), occurs in the ZF. In 

contrast to the ZG, which lacks the steroid 

17α-hydroxylase enzyme necessary for the 

formation of cortisol precursors, cortisol is 

available as a substrate for aldosterone synthase 

in the ZF. Hence, cortisol is converted 

into the ‘hybrid steroids’ 18-hydroxycortisol 

and 18-oxocortisol, the levels of which are 

elevated in patients with FH-I. 2 

The second recognized form of familial 

hyperaldosteronism (FH-II) is neither 

gluco corticoid-suppressible nor associ ated 

with the hybrid gene mutation. 3 Approximately 

30% of patients with FH-II have 

uni lateral forms of primary aldosteronism 

(mostly due to an aldosterone-producing 

ade noma [APA]), with the remainder 

being bilateral (due to bilateral adrenal 

hyper plasia [BAH]). The genetic basis of 

FH-II remains uncertain and is almost certainly 

hetero geneous; several families have 

demon strated linkage of FH-II with a locus 

at chromosome 7p22. 3 

In 2011, Mulatero and colleagues assessed 

prevalence rates of familial hyper aldo steronism 

among 300 patients consecutively 

diag nosed with primary aldosteronism, 

after exclud ing those suspected or diagnosed 

as having a form of familial primary 

aldo steronism. 4 Hybrid gene testing yielded 

only two (0.7%) patients with FH-I. Of 

the remaining 298 study participants, 199 

had relatives available for and consenting 

to bio chemical screening by aldosterone– 

renin ratio (ARR) testing and, where positive, 

definitive confirmation or exclusion 

of primary aldo steronism by saline infusion 

testing. This analysis revealed that 12 

patients had at least one affected relative, 

result ing in a preva lence of FH-II of at least 

6% (almost 10-fold that of FH-I). The prevalence 

could be higher, as another 54 patients 

were classified as having ‘uncertain’ status, 

either because not all family members 

with hypertension underwent ARR testing 

or because testing of family members 

was inconclusive. 4 

In a major breakthrough towards further 

understanding the genetic basis of primary 

aldosteronism, Choi and col leagues 

reported somatic mutations (Gly151Arg and 

Leu168Arg) in KCNJ5, which encodes an 

inwardly-rectifying K + channel, in eight of 22 

patients with APA. 5 A third, germline mutation 

in KCNJ5 (Thr158Ala) had pre viously 

been identified in affected members of a 

US family with a new familial form of primary 

aldosteronism (FH-III). 6 The affected 

father and two daughters demon strated 

very severe primary aldo steronism, with 

childhood-onset hyper tension, hypo kalemia 

and markedly elevated aldosterone and 

sup pressed renin levels. As in patients with 

FH-I, 18-hydroxycortisol and 18- oxocortisol 

levels were elevated, albeit to a greater 

degree. How ever, the primary aldosteronism 

was not glucocorticoid-suppressible, and 

the hybrid gene mutation was not present. 

Resected adrenal glands showed marked, 

diffuse hyperplasia of the ZF, with the combined 

weight of both adrenal glands in one 

daughter reaching 81 g (normal

ENDOCRINOLOGY 


■ Familial hyperaldosteronism type II (FH-II) 

may account for at least 6% of primary 

aldosteronism cases and is approximately 

5–10 times more common than FH-I 4 

■ A germline mutation in KCNJ5 is 

associated with severe, early-onset 

familial primary aldosteronism, and 

somatic KCNJ5 mutations are common in 

aldosterone-producing adenoma 5 

■ Patients with primary aldosteronism have 

reduced circulating levels of endothelial 

progenitor cells, which might contribute 

to the development of vasculopathy in 

these individuals 9 

■ The degree of left ventricular enlargement 

in primary aldosteronism is largely 

determined by dietary salt; dietary salt 

restriction might reduce cardiovascular 

risk in this condition 10 

their origin? Do KCNJ5 mutations bestow 

ZF-like characteristics (including his tology, 

17α-hydroxylase expression, hybrid 

steroid formation, and loss of aldosterone 

responsive ness to angiotensin-II) to ZG 

cells, or are ZG-like characteristics (aldosterone 

synthase expression) bestowed onto 

ZF cells? Further studies should shed light on 

this fascinating issue. 

Other studies in 2011 have focused on 

the mechanisms underlying adverse cardiovascular 

effects of aldosterone excess. In a 

novel study by Wu et al., 9 levels of endothelial 

progenitor cells (EPCs), which are 

thought to protect against cardiovascular 

disease by repairing endothelial injury, were 

lower in 113 patients with primary aldosteronism 

(APA n = 87; BAH n = 26) than 

in 55 patients with essential hypertension. 9 

Differences in pulse-wave velocity, a marker 

of arterial stiffness, and high- sensitivity 

C-reactive protein (hsCRP) levels, a marker 

of cardiovascular inflammation, and EPC 

counts were attenuated following unilateral 

adrenalectomy or during treatment 

with aldosterone antagonists. Overall, the 

findings suggest that increased circulating 

aldosterone levels in patients with primary 

aldosteronism contribute to vasculopathy 

by reducing EPC numbers, partly by activating 

EPC mineralocorticoid receptors and 

possibly indirectly by raising hsCRP levels. 9 

Animal studies have demonstrated a critical 

role for salt in the development of aldosterone-induced 

cardiovascular damage; 

how ever, corroborative data in humans were 

lack ing. In a case–control study of 21 patients 

with primary aldosteronism and 21 matched 

individuals with essential hyperten sion, 

Pimenta and co-workers reported in 2011 

that patients with primary aldosteronism 

had greater thickness of the left ventricular 

wall, end-diastolic dia meter and mass. Moreover, 

urinary sodium excretion, a mar ker 

of dietary salt intake, positively correlated 

with and was an indepen dent predictor of 

left ventricular wall thickness and mass in 

patients with pri mary aldosteronism, but 

not in those with essential hypertension. 10 

Hence, as in animal studies, salt appears 

to interact with auto nomous aldosterone 

excess to bring about cardio vascular damage 

in patients with primary aldosteronism. The 

lack of a posi tive correlation between plasma 

aldoster one and left ventricular dimen sions 

in patients with primary aldosteronism 

raises the possibility that, above a certain 

thres hold, aldosterone plays a more permissive 

part, whereas salt has a more graduated 

effect. Either way, these results argue for a 

role of dietary salt restriction to reduce the 

risk of cardiovascu lar disease in patients with 

primary aldosteronism. 

Endocrine Hypertension Research Center, 

University of Queensland School of Medicine, 

Greenslopes and Princess Alexandra Hospitals, 

Ipswich Road, Woolloongabba, Brisbane 4102, 

Australia. 

m.stowasser@uq.edu.au 


The author declares no competing interests. 

1. Sutherland, D. J., Ruse, J. L. & Laidlaw, J. C. 

Hypertension, increased aldosterone secretion 

and low plasma renin activity relieved by 

dexamethasone. Can. Med. Assoc. J. 95, 

1109–1119 (1966). 

2. Lifton, R. P. et al. Hereditary hypertension 

caused by chimaeric gene duplications and 

ectopic expression of aldosterone synthase. 

Nat. Genet. 2, 66–74 (1992). 

3. Stowasser, M., Pimenta, E. & Gordon, R. D. 

Familial or genetic primary aldosteronism and 

Gordon syndrome. Endocrinol. Metab. Clin. North 

Am. 40, 343–368, viii (2011). 

4. Mulatero, P. et al. Prevalence and characteristics 

of familial hyperaldosteronism: the PATOGEN 

study (Primary Aldosteronism in TOrino-GENetic 

forms). Hypertension 58, 797–803 (2011). 

5. Choi, M. et al. K + channel mutations in adrenal 

aldosterone-producing adenomas and 

hereditary hypertension. Science 331, 768–772 

(2011). 

6. Geller, D. S. et al. A novel form of human 

mendelian hypertension featuring 

nonglucocorticoid-remediable aldosteronism. 

J. Clin. Endocrinol. Metab. 93, 3117–3123 

(2008). 

7. Gordon, R. D., Hamlet, S. M., Tunny, T. J. & 

Klemm, S. A. Aldosterone-producing adenomas 

responsive to angiotensin pose problems in 

diagnosis. Clin. Exp. Pharmacol. Physiol. 14, 

175–179 (1987). 

8. Tunny, T. J., Gordon, R. D., Klemm, S. A. & 

Cohn, D. Histological and biochemical 

distinctiveness of atypical aldosteroneproducing 

adenomas responsive to upright 

posture and angiotensin. Clin. Endocrinol. (Oxf.) 

34, 363–369 (1991). 

9. Wu, V. C. et al. Endothelial progenitor cells in 

primary aldosteronism: a biomarker of severity 

for aldosterone vasculopathy and prognosis. 


(2011). 

10. Pimenta, E. et al. Cardiac dimensions are largely 

determined by dietary salt in patients with 

primary aldosteronism: results of a case– 

control study. J. Clin. Endocrinol. Metab. 96, 

2813–2820 (2011). 

POLYCYSTIC OVARY SYNDROME IN 2011 

Genes, aging and sleep apnea 

in polycystic ovary syndrome 

Andrea Dunaif 

Polycystic ovary syndrome (PCOS) is a complex genetic disease that 

affects approximately 7% of women of reproductive age worldwide. From 

novel pathways implicated in the etiology of PCOS through genome-wide 

association to characterization of the reproductive and metabolic changes 

that occur in ageing women with PCOS, the year 2011 has seen a number 

of studies published that highlight the intricacies of this condition. 

Dunaif, A. Nat. Rev. Endocrinol. 8, 72–74 (2012); published online 20 December 2011; 

doi:10.1038/nrendo.2011.227 

The year 2011 saw the advent of the first 

genome-wide association study (GWAS) in 

polycystic ovary syndrome (PCOS). 1 GWAS 

have been widely used, since the publication 

of the human haplotype map in 2005, 

to localize susceptibility genes for com plex 

traits, such as obesity and type 2 dia betes 

mellitus (T2DM). 2 This analysis per mits 

an unbiased examination of the entire 

genome for novel disease susceptibility loci 

and, unlike candidate gene approaches, is 

hypothesis-generating. 2 The first GWAS 

of PCOS was conducted in Han Chinese 

women with PCOS, who were diagnosed 


using the Rotterdam cri teria (two of three 

of the following findings: oligomenor rhea, 

hyperandrogen ism and/or poly cystic ovaries 

detected on ultrasono graphy). 1 Asso cia tions 

achiev ing genome-wide levels of significance 

3 between PCOS and loci on chromosomes 

2p16.3 (OR 0.71), 2p21 (OR 0.67) 

and 9q33.3 (OR 1.34) were observed in a 

dis covery sample of 744 PCOS cases and 

895 con trols and in two indepen dent replication 

cohorts of 2,840 PCOS cases and 5,012 

controls, and 498 PCOS and 780 controls. 1 

Several known genes are located near 

the locus at 2p16.3, which showed the 

great est association with PCOS, includ ing 

GTF2A1L and LHCGR. GTF2A1L, which 

encodes TFIIAα/β-like factor (ALF), is a 

germ-cell-specific transcription factor that 

is highly expressed in adult testis and may 

play a part in spermato genesis. How variation 

in GTF2A1L might contribute to PCOS 

is unclear. LHCGR encodes the lutropin– 

choriogonadotropic hormone recep tor 

(LH/CG-R) and is a highly plau si ble PCOS 

candidate gene. The strongest asso ci ation 

at the locus on chromo some 2p21 was with 

THADA, a gene origi nally iden tified in thy - 

roid adenomas. A GWAS in white individuals 

of European ances try reported an 

associa tion of THADA with T2DM. 4 The 

region on chromosome 9q33.3 associ ated 

with PCOS was located within DENND1A, 

which encodes a domain differen tially 

expressed in normal and neoplastic cells 

(DENN) that can bind to and negatively 

regulate endo plasmic reticulum aminopeptidase 

1. Elevations of circulating endoplasmic 

reti culum amino peptidase 1 have 

been reported in obese women with PCOS. 

Thus, it is possible that varia tion in THADA 

and DENND1A contribute to T2DM and 

obesity risk in women with PCOS. 

Confirmation that the GWAS signals 

reflect a variation in these genes, rather 

than in other genes that are in linkage disequilibrium 

with these loci, requires further 

genetic analyses. In addition, the roles 

of these loci in PCOS suscepti bility in other 

racial or eth nic groups and in other phenotypes, 

for instance, in women with PCOS 

diag nosed using the National Insti tute of 

Child Health and Human Develop ment 

(NICHD) criteria (history of oligo menorrhea 

and clinical and/or biochemi cal evidence of 

hyper androgenism), will require further 

investigation. Studies in monozygotic twins 

indicate that the herit ability of PCOS is 

close to 80%. However, the loci identified 

in the PCOS GWAS confer modest (~30%) 

changes in disease risk and do not account 


■ Three genetic susceptibility loci 

have been mapped by genome-wide 

association study in Han Chinese women 

with PCOS 1 

■ Increased ovarian and adrenal androgen 

production and insulin resistance persist 

in postmenopausal women with PCOS 6,7,8 

■ Obstructive sleep apnea contributes 

to insulin resistance and continuous 

positive airway pressure improves insulin 

sensitivity in women with PCOS 10 

for the observed herit ability of PCOS. 5 This 

so-called ‘missing heritability’ has been seen 

in other common complex traits, such as 

T2DM, and might reflect the fact that rare 

rather than common variants contribute 

to complex diseases. 5 Nevertheless, GWAS 

has been important for implicating novel 

b iologic pathways in disease pathogenesis. 

Little was known about the reproductive 

and metabolic changes that occur with age 

in women with PCOS. In 2011, two crosssectional 

studies compared postmenopausal 

women in the sixth decade of life with 

and without PCOS. 6,7 In both studies, the 

diagnosis of PCOS was made on the basis 

of the NICHD diagnostic criteria, although 

the study by Puurunen et al. 7 also contained 

premenopausal women with PCOS 

diagnosed by the Rotterdam criteria and a 

control group consisting of reproductively 

normal, premenopausal women. The study 

by Markopoulos et al. 6 found that postmenopausal 

women with PCOS had significantly 

elevated levels of circulating total 

testosterone, androstenedione, dehydroepiandrosterone 

sulfate (DHEAS) and 

17-hydroxyprogesterone and an increased 

free androgen index (FAI). Sex hormonebinding 

globulin (SHBG) levels, how ever, 

were significantly decreased compared 

with the control group. No evidence of 

increased sensitivity to corticoliberin 

(also known as 

corticotropin- releasing 

hormone) or adrenocortico 

tro pic hormone 

was reported in women 

with PCOS, which suggests 

that increases in 

adrenal androgen production 

did not result from changes in responsiveness 

to tropic hor mones. Dexamethasone 

suppression sug gested that elevated total 

testosterone and DHEAS levels were partly 

adrenal in origin. Puurunen et al. 7 also found 

increased androstenedione levels, basally 

and in response to chorio gonado tropin, 

ENDOCRINOLOGY 

in postmenopausal women with PCOS 

compared with postmenopausal control 

women. Furthermore, they found persistent 

evidence for insulin resistance and increased 

inflammation, independent of BMI, in postmenopausal 

women with PCOS compared 

to those without the disease. 

In a 2011 prospective study, Schmidt et al. 8 

diagnosed PCOS on the basis of ovarian 

histology from ovarian wedge resec tion or 

unilateral oophorectomy per formed in 1956– 

1965. These women were examined in 1987 

and compared with control women from a 

population-based study. Both groups were 

recalled for repeat examination in 2008, in 

their eighth decade of life. The PCOS group 

had higher FAI and lower follitropin (also 

known as follicle-stimulating hormone; 

FSH) and SHBG levels than the control 

group, as was the case in 1987. DHEAS, total 

testo sterone and androstenedione levels were 

significantly increased in premenopausal 

women with PCOS in 1987, but were similar 

to those of the control group after menopause. 

The prevalence of hypo thyroidism 

was lower in post menopausal women with 

PCOS than in control individuals. 

Taken together, these three studies 6,7,8 suggest 

that hyperandrogenism of both ova rian 

and adrenal origin, as well as insulin resistance, 

persist in postmenopausal women 

with PCOS. Increased androgen levels 

declined with age in older post menopausal 

women with PCOS such that only differences 

in FAI were present in women aged 

>70 years. 8 By contrast, decreases in SHBG 

and FSH levels persist into old age. All of 

the studies are limited by small sample sizes, 

which might account for the differences 

in the prevalence of hypothyroidism. In 


ENDOCRINOLOGY 

the cross-sectional studies, the accuracy of 

diagnosis of PCOS on the basis of medical 

records is a potential limitation, although 

oligo menorrhea and symptoms of androgen 

excess, such as hirsutism, have been shown 

to be excellent proxies for PCOS. 9 

The prevalence of obstructive sleep apnea 

(OSA) is significantly increased in women 

with PCOS, independent of obesity—a wellknown 

risk factor for OSA. Androgen levels 

and insulin resistance are positively associated 

with OSA in PCOS. In 2011, Tasali and 

colleagues proposed that OSA contributes 

to insulin resistance in PCOS, as it does in 

other OSA populations. 10 The investigators 

directly tested this hypothesis by treating 

affected women with continuous positive 

airway pressure (CPAP), which resulted in a 

modest but significant improvement in 

insulin sensitivity. 10 A dose–response effect 

of CPAP on insulin sensitivity was observed, 

with greater improvements in sensitivity 

with longer duration of CPAP. A significant 

decrease in circulating norepinephrine 

levels was also reported, without changes in 

epinephrine, cortisol or leptin levels. This 

observation suggests that the decrease in 

insulin sensitivity is mediated by sympathetic 

nervous system activation. Diastolic 

blood pressure, which was not elevated in 

women with PCOS who had OSA, decreased 

significantly with CPAP. 

The limitations of this study were the small 

number of women (n = 9) who completed the 

CPAP intervention with acceptable compliance 

(≥4 h of use per night). 10 Furthermore, 

the study population was extremely 

obese, with a mean BMI of 48.4 kg/m 2 . 

The improvements in insulin sensitivity, 

although significant, were very modest (on 

average 7%); the study par ticipants remained 

profoundly insulin resistant after CPAP 

treatment. Modeling of the data suggested 

that the beneficial effect of CPAP would 

be greater in overweight or mildly obese 

patients with PCOS. How ever, the robustness 

of the model is questionable given the 

small sample size. Never the less, this study 

suggests that OSA con tributes to insulin 

resistance in PCOS and that CPAP improves 

insulin sensitivity in affected women. 

In conclusion, these 2011 publications 

will have a major effect on the field. It is now 

clear from an adequately powered and replicated 

study that genetic variation contributes 

to the etiology of PCOS. Furthermore, 

reproductive and metabolic features of the 

dis order persist beyond the reproductive 

years, increasing the impact of PCOS as 

a leading women’s health issue. Finally, a 

component of the insulin resistance associated 

with PCOS is secondary to OSA and 

improves with CPAP treatment. 

Division of Endocrinology, Metabolism and 

Molecular Medicine, Northwestern University 

Feinberg School of Medicine, 303 East Chicago 

Avenue, Tarry 15‑745, Chicago, IL 60611, USA. 

a‑dunaif@northwestern.edu 



1. Chen, Z. J. et al. Genome-wide association 

study identifies susceptibility loci for polycystic 

ovary syndrome on chromosome 2p16.3, 2p21 

and 9q33.3. Nat. Genet. 43, 55–59 (2011). 

2. Hirschhorn, J. N. & Daly, M. J. Genome-wide 

association studies for common diseases and 

complex traits. Nat. Rev. Genet. 6, 95–108 

(2005). 

3. Hoggart, C. J., Clark, T. G., De Iorio, M., 

Whittaker, J. C. & Balding, D. J. Genome-wide 

significance for dense SNP and resequencing 

data. Genet. Epidemiol. 32, 179–185 (2008). 

4. Zeggini, E. et al. Meta-analysis of genome-wide 

association data and large-scale replication 

identifies additional susceptibility loci for type 2 

diabetes. Nat. Genet. 40, 638–645 (2008). 

5. Manolio, T. A. et al. Finding the missing 

heritability of complex diseases. Nature 461, 

747–753 (2009). 

6. Markopoulos, M. C. et al. Hyperandrogenism in 

women with polycystic ovary syndrome 

persists after menopause. J. Clin. Endocrinol. 

Metab. 96, 623–631 (2011). 

7. Puurunen, J. et al. Unfavorable hormonal, 

metabolic, and Inflammatory alterations persist 

after menopause in women with PCOS. J. Clin. 

Endocrinol. Metab. 96, 1827–1834 (2011). 

8. Schmidt, J., Brännström, M., Landin- 

Wilhelmsen, K. & Dahlgren, E. Reproductive 

hormone levels and anthropometry in 

postmenopausal women with polycystic ovary 

syndrome (PCOS): a 21-year follow-up study of 

women diagnosed with PCOS around 50 years 

ago and their age-matched controls. J. Clin. 


9. Taponen, S. et al. Hormonal profile of women 

with self-reported symptoms of 

oligomenorrhea and/or hirsutism: Northern 

Finland Birth Cohort 1966 Study. J. Clin. 


10. Tasali, E., Chapotot, F., Leproult, R., 

Whitmore, H. & Ehrmann, D. A. Treatment of 

obstructive sleep apnea improves 

cardiometabolic function in young obese 

women with polycystic ovary syndrome. J. Clin. 


EPIGENETICS AND METABOLISM IN 2011 

Epigenetics, the life-course 

and metabolic disease 

Peter D. Gluckman 

Clinical and experimental studies suggest that early life experiences, 

perhaps spanning multiple generations, affect lifelong risk of metabolic 

dysfunction through epigenetic mechanisms. Data published in 2011 

suggest that epigenetic analysis could potentially have utility as a marker 

of early metabolic pathology and might enable early life prophylaxis. 

Gluckman, P. D. Nat. Rev. Endocrinol. 8, 74–76 (2012); published online 20 December 2011; 

doi:10.1038/nrendo.2011.226 

Both population and individual variation 

in sus ceptibility to an obesogenic environment 

exist. Genome-wide association studies 

have been disappointing in explaining this 

variation, and there is a growing focus on 

possible epigenetic explanations. Epigenetic 

variation is most likely to arise early in the 

life-course. An extensive body of experimental, 

clini cal and epidemiological evidence 

demon strates that early life develop mental 

factors— including the maternal diet, but 

operating within the normative range of 

develop mental exposures—affect the risk 

of developing meta bolic disease later in life. 1 

This phe nomenon is sometimes termed 

developmental programming. The early 

observations were largely ignored because 

of the absence of a plausible biological 

mechanism, but explana tions developed 

over the past decade have been framed in 

terms of developmental plasticity—the 

adaptive processes enabling an organism 

to respond to environmental cues acting in 

early life and adjust its develop mental trajectory. 

Developmental plasticity is at least 

partly underpinned by epigenetic mechanisms, 

including DNA methylation and 

histone modifications. A number of papers 

published during 2011 have re inforced the 

validity of these conclusions. 

Extensive previous work has shown that 

rats whose mothers are underfed during 

preg nancy and lactation develop an insulin 

resis tant and obese phenotype in adulthood. 

Moreover, mice lacking the transcription 

factor hepatocyte nuclear factor 4α 


(HNF-4α), a crucial regulator of gene expression 

in pancreatic islet β cells, have impaired 

glucose tolerance. In 2011, Sandovici et al. 

reported how maternal diet in rats affects the 

epigenetic regulation of the Hnf4a locus in 

pancreatic islets of offspring. 2 The researchers 

found that a low-protein maternal diet 

led to underexpression of Hnf4a in the islets 

of the offspring. Mechanistically, the underexpression 

could be attributed in part to 

his tone modifications at the gene enhancer 

region of Hnf4a, which led to changes in 

chromatin looping that ultimately weakened 

the interaction between the enhancer region 

and a specific promoter region. The normative 

age-dependent epigenetic silencing 

of the Hnf4a locus was exacerbated in rats 

exposed in utero to a low-protein diet. These 

data add to the growing experimental literature 

showing epigenetic consequences from 

the manipulation of early life undernutrition 

in metabolically relevant tissues. 

Previous studies in rats have shown that 

neonatal administration of the adipokine 

leptin can reverse developmental programming 

leading to metabolic compromise as 

well as some of the associated epi genetic 

changes. 3 Such studies are provocative 

in that they suggest that develop mental 

program ming in humans might be reversible. 

Pinney et al. examined how administration 

of exenatide, an analogue of the 

incretin glucagon-like peptide 1, acts to 

prevent the development of glucose intolerance 

in adulthood in rats subjected to intrauterine 

growth restriction. 4 Rats subjected 

to this abnormal intrauterine environ ment 

develop glucose intolerance and are characterized 

by progressive epi genetic silencing 

of pancreatic islet transcription factor 

Pdx1. The 2011 paper found that injection 

of exenatide during postnatal day 1–6 in 

rats after intrauterine growth restriction 

increased Pdx1 transcription by normalizing 

post-translational and epigenetic changes 

© Paul Hakimata | Dreamstime.com 


related to this gene, including Pdx1 activator 

phosphorylation, histone acetylation and 

trimethylation, and DNA methylation at the 

CpG island in the Pdx1 promoter. Exenatide 

is already in use in the treatment of adults 

with type 2 diabetes mellitus (T2DM), and 

this study provides an experimental proof 

of concept for its usage early in life prior to 

disease onset. 

Prophylactic treatment of at-risk individuals 

early in life is generally more efficacious 

and provides greater health and cost 

benefits than treatment after a disease 

de velops. This is particularly the case for 

diseases such as diabetes mellitus, where 

the cost of treat ing associated morbidities 

and complica tions compounds over many 

years. How ever, beyond the obvious research 

program that would be needed to validate 

such interventions, a challenge remains: 

how do we identify infants whose particular 

developmental programming has placed 

them at increased metabolic risk? Birth 

weight is not a satisfactory proxy, given that 

metabolically adverse developmental programming 

can occur independent of birth 

weight. 5 A recent paper by Godfrey et al. 

—to which I contributed—has suggested that 

the epigenetic state at birth can both predict 

childhood adiposity and be a measure of prenatal 

nutritional exposures. 6 Umbilical cord 

tissue-derived DNA was sourced from two 

independent large-scale prospective cohorts, 

and the methylation status at specific CpGs 

in the promoter region of RXRα, which 

encodes a transcription factor involved in 

fat metabolism and insulin sensitivity, was 

measured after a preliminary genome-wide 

scan. A positive correlation between degree 

of RXRα methyla tion at one specific site in 

the promoter and childhood body adiposity 

at age 6 years or 9 years was found in 

both within-cohort and between-cohort 

replicates. Additionally, a negative association 

was observed between mater nal carbohydrate 

intake during the first tri mes ter of 

pregnancy and the degree of methylation at 

ENDOCRINOLOGY 

■ Changes in promoter–enhancer interactions underlie the epigenetic regulation of a 

transcription factor in rat pancreatic islets induced by poor maternal diet 2 

■ The trajectory towards onset of type 2 diabetes mellitus (T2DM) in the growth-compromised 

newborn rat can be reversed by an incretin analogue that normalizes epigenetic 

modifications associated with pancreatic β-cell dysfunction 4 

■ Strong relationships exist between epigenotype at birth and later adiposity, and between 

maternal nutrition and offspring epigenotype in humans 6 

■ The epigenetic states of genes associated with T2DM and obesity might be a 

presymptomatic marker of the lifetime risk of T2DM in humans 7 

■ The phenotypic effects of early life overnutrition can be transgenerationally transmitted 

through the paternal line in mice 9 

this site. In contrast to the small effect sizes 

typically seen with genetic polymorp hisms 

associated with metabolic disease risk, this 

single site epigenotype could account for 

at least 25% of the variance in child hood 

adipo sity. This association was obser ved 

across a healthy population, indicating 

that develop mental programming of metabolic 

risk and associated epigenetic variation 

occurs across the normative range of 

developmental experiences. 

Genes for which polymorphisms have 

strong associations with disease risk might 

be anticipated to have epimutations (aberrant 

epigenetic marks). One such gene is 

FTO, which has been identified by genomewide 

association studies as being involved 

in obesity risk. In a prospective study of 

nonsymptomatic indivi duals of a mean age 

of 30 years by Toperoff et al., 7 those who 

showed hypomethylation at an intronic 

CpG site of FTO in blood samples had 

an increased risk of develop ing impaired 

glucose metabolism by a mean age of 

43 years. This pattern was also seen in a 

sepa rate case–control analysis, although the 

level of hypomethylation in cases relative to 

controls was small, as was the effect size. 7 

These findings were made in a tissue not 

specifically related to metabolic function, 

and the differential methylation levels may 

have been established in early development 

before major cell differentiation had 

occurred, although this inference is contingent 

on the long-term stability of the FTO 

epigenotype after its establishment. The 

methylation levels could not be explained 

by the presence or absence of the risk allele, 

indicating that their association with disease 

risk was independent of DNA sequence. 

Global prevalence of maternal obesity 

and ges tational diabetes mellitus is rising, 

and both are risk factors for the development 

of meta bolic disorder in offspring; 8 

there fore, the potential for an escalating 

prevalence of intergenerationally induced 

T2DM is a par ticular concern. Epigenetic 


ENDOCRINOLOGY 

mechanisms could underlie the intergenerational 

transmis sion of predisposition 

to T2DM, but unraveling the mechanisms 

involved is highly complex owing to the 

multiple pathways by which nongenomic 

inheritance, involving either direct or indirect 

epi genetic mechanisms, could occur. 

Dunn and Bale utilized a maternal high-fat 

diet mouse model and sought to eliminate 

maternal physiological or behavioral effects 

and grand-maternal effects by studying 

pheno typic outcomes up to the F3 generation 

through the paternal line. 9 They found 

that female-specific increased body weight 

and length was inherited through the 

pater nal, not the maternal, lineage. Taken 

together with other research show ing that 

specific histone marks located at developmental 

loci in sperm are maintained beyond 

spermio genesis, 10 this research suggests that 

the phenotype was transmitted through the 

male germline via stable epigenetic marks 

in sperm. 

Our knowledge of developmental pathways 

to metabolic disease is rapidly increasing. 

It is becoming apparent that epi genetic 

variations induced early in life or that are 

present later in life are associated with metabolic 

risk. How far environ mentally induced 

plasticity, associated with epi genetic changes 

that have metabolic sequelae, operates into 

the life-course is, how ever, not yet clear. 

Research to date has largely been based on a 

candidate gene approach, but newer methodologies 

in sequencing that enable whole 

genome approaches, such as ChIP-Seq 

(chromatin immuno precipitation together 

with massively parallel DNA sequencing), 

should allow more rapid develop ment of 

understandings. Many potential methodological 

pitfalls exist, and the importance 

of validation across multiple cohorts is 

emphasized in the work of Godfrey et al., 

who found an apparently impressive association 

between adiposity and methylation at 

the endothelial nitric oxide synthase gene 

NOS3, which could not be validated in a 

second cohort. 

Strategies could emerge whereby epigenetic 

state at birth or in infancy could be 

used to assess developmental exposures, to 

pre dict metabolic risk and to assist in the 

iden tification of new preventative or therapeutic 

approaches. Indeed the work with 

exena tide discussed above 4 could be considered 

an experimental proof of concept; 

the chal lenge would be to find valid risk 

markers and acceptable interventions. The 

outlook for epigenetic research in human 

metabolic and other diseases is promising. 

Liggins Institute, The University of Auckland, 

Private Bag 92019, Auckland 1142, 

New Zealand. 

pd.gluckman@auckland.ac.nz 

Acknowledgments 

F. Low provided assistance with reviewing 

the literature. 



1. Fernandez-Twinn, D. S. & Ozanne, S. E. Early 

life nutrition and metabolic programming. Ann. 

NY Acad. Sci. 1212, 78–96 (2010). 

2. Sandovici, I. et al. Maternal diet and aging alter 

the epigenetic control of a promoter–enhancer 

interaction at the Hnf4a gene in rat pancreatic 

islets. Proc. Natl Acad. Sci. USA 108, 

5449–5454 (2011). 

3. Gluckman, P. D. et al. Metabolic plasticity 

during mammalian development is directionally 

dependent on early nutritional status. Proc. 

Natl Acad. Sci. USA 104, 12796–12800 

(2007). 

4. Pinney, S., Jaeckle Santos, L., Han, Y., 

Stoffers, D. & Simmons, R. Exendin-4 

increases histone acetylase activity and 

reverses epigenetic modifications that silence 

Pdx1 in the intrauterine growth retarded rat. 

Diabetologia 54, 2606–2614 (2011). 

5. Gale, C. R. et al. Maternal diet during pregnancy 

and carotid intima-media thickness in children. 

Arterioscler. Thromb. Vasc. Biol. 26, 1877–1882 

(2006). 

6. Godfrey, K. M. et al. Epigenetic gene promoter 

methylation at birth is associated with child’s 

later adiposity. Diabetes 60, 1528–1534 

(2011). 

7. Toperoff, G. et al. Genome-wide survey reveals 

predisposing diabetes type 2-related DNA 

methylation variations in human peripheral 

blood. Hum. Mol. Genet. http://dx.doi.org/ 

10.1093/hmg/ddr472. 

8. Poston, L., Harthoorn, L. F. & Van Der 

Beek, E. M. on behalf of contributors to the ILSI 

Europe workshop. Obesity in pregnancy: 

implications for the mother and lifelong health 

of the child. a consensus statement. Pediatr. 

Res. 69, 175–180 (2011). 

9. Dunn, G. A. & Bale, T. L. Maternal high-fat diet 

effects on third-generation female body size via 

the paternal lineage. Endocrinology 152, 

2228–2236 (2011). 

10. Hammoud, S. S. et al. Distinctive chromatin in 

human sperm packages genes for embryo 

development. Nature 460, 473–478 (2009). 

OSTEOPOROSIS IN 2011 

Osteoporosis therapy—dawn 

of the post-bisphosphonate era 

Roland Baron 

Over the past decade, investigators have actively searched for 

safer therapeutic approaches to replace or complement the use 

of bisphosphonates and/or parathyroid hormone, exploring both 

antiresorptive and osteoanabolic pathways. Besides marked progress 

in basic research, the year 2011 has seen several compounds for the 

treatment of osteoporosis enter or progress within clinical trials. 

Baron, R. Nat. Rev. Endocrinol. 8, 76–78 (2012); published online 6 December 2011; 

doi:10.1038/nrendo.2011.207 

Osteoporosis is characterized by a marked 

decrease in BMD and strength, resulting 

in fragility fractures associated with high 

morbidity and mortality. The development 

of bis phosphonates has substantially 

altered the course of the disease in treated 

patients. This class of drugs binds rapidly 

to the mineral ized skeleton and impairs the 

process of bone resorption, which leads to a 

progressive increase in BMD and a decrease 

in the risk of fractures, albeit mostly in vertebral 

rather than hip or other non vertebral 

fractures. However, as bone resorption and 

bone formation are linked by the process of 

bone remodeling, the anti resorptive effect 

of these drugs rapidly decreases bone formation 

and tissue turnover, limiting the 

gain in BMD. This progressive decrease in 

bone turnover and the persistent effect of 

bis phosphonates even years after their withdrawal 

might contribute to two undesirable 

long-term adverse effects: osteonecrosis of 

the jaw and atypical femoral fractures. 

In addition to bisphosphonates, within 

the past few years osteoporosis treatment 

has seen the arrival of the first osteo anabolic 

drugs: injectable parathyroid hormone 

(PTH) fragments. When administered 

daily, PTH, unlike bisphosphonates, initially 

induces clear increases in the levels 

of bone formation markers, bone turnover 

and BMD. The combination of PTH with 

bisphosphonates, especially when the latter 

are given at long intervals, has some additive 

effects over monotherapy with either 

compound. 1 Yet, the effects of PTH wane 

with time, and a concomitant increase in 

bone resorption can be observed. Moreover, 


some concerns have been raised over the 

drug’s oncogenic potential. As a result, academic 

and industry laboratories have been 

engaged in active research over the past 

decade to find safer therapeutic approaches, 

both antiresorptive and osteoanabolic, 

to replace or complement the use of bisphosphonates 

and/or PTH. Besides significant 

advances in basic science, the year 

2011 has seen several compounds enter or 

progress within clinical trials. 

Mutations in the gene encoding sclerostin, 

an osteocyte-derived Wnt antagonist, 

cause sclerosteosis or van Buchem disease, 

two high-bone-mass syndromes. 2,3 Together 

with pre vious findings, these observations 

made a strong case for develop ing antagonists 

to this protein. The year 2011 has seen 

the first clinical trial of a humanized monoclonal 

antibody to sclerostin (AMG785) in 

healthy men and postmenopausal women. 4 

In this phase I, randomized, double-blind, 

placebo- controlled study, 72 healthy individuals 

received a single subcutaneous or 

intravenous injection of ascending doses 

of the antibody and were followed up for a 

maximum of 85 days. The results showed 

not only a dose-dependent increase in the 

levels of several bone formation markers 

but also a decrease in those of bone resorption 

markers. Despite the short duration of 

the study, significant increases in BMD 

of up to 5% in the spine and 3% in the hip 

were measured. In this short period, the 

compound was safe and well-tolerated. Six 

patients, however, developed anti-AMG785 

antibodies, which were neutralizing in two 

individuals—a reason for some con cern. 

Never theless, this trial demonstrates the 

valid ity of this novel therapeutic approach, 

which stands out not only because of its 

efficacy but also owing to its mechanism 

of action, being possibly both anabolic and 

antiresorptive. A phase II study has been 

completed, and next year will undoubtedly 

bring more data on this development 

program. In the long term, and despite the 

fact that haploinsufficient sclerosteosis 

or van Buchem mutation carriers experience 

no significant adverse effects, the 

risks of foramen closures due to bone overgrowth 

and the potential oncogenicity of 

this thera peutic approach will have to be 

carefully examined. 

The search for antiresorptive compounds 

that do not remain in bone for long periods 

of time and/or that decrease bone resorption 

without negative effects on bone formation 

has also been active. One approach has been 

to block the differentiation of osteoclasts by 


■ A single injection of humanized 

antibodies to sclerostin, an endogenous 

Wnt antagonist secreted mostly by 

osteocytes, markedly raised markers 

of bone formation and decreased 

markers of bone resorption, increasing 

BMD over a short period of time in a 

phase I clinical trial 4 

■ Orally delivered inhibitors of cathepsin K 

increased BMD continuously at all bone 

sites over a 3-year period in extensions 

of phase II clinical trials 9,10 

■ Antibodies to RANKL reduced the 

incidence of vertebral and hip fractures 

in women at high risk 7 

■ Discontinuation of cathepsin K inhibitors 

or antibodies to RANKL induced a rapid 

increase in bone turnover and return to 

pre-treatment BMD values 8,9 

antagonizing RANKL, a cytokine that is 

required for osteoclast formation, through 

the use of antibodies. Detailed analysis of 

the effect of denosumab, a human monoclonal 

antibody against RANKL, on bone 

turnover markers confirmed that it induces 

a very rapid, profound and sustained 

decrease in bone resorption markers, but 

also in bone formation markers. 5 This finding 

con firmed that denosumab induces a 

marked decrease in bone turnover, which 

indeed reaches levels below the premenopausal 

reference interval. Although 

this decrease could be of some concern on 

the basis of our previous experi ence with 

bis phosphonates, no adverse skeletal effects 

were noted after 3 years of denosumab 

therapy in the FREEDOM trial. 6 The study 

is being extended for 10 years, which should 

adequately address long-term safety issues. 

Des pite these theoretical concerns, another 

study in postmenopausal women at high 

risk of fractures has demonstrated that 

denosumab efficiently reduces the incidence 

of new vertebral and hip fractures in highrisk 

sub groups. 7 Of the 7,808 women enrolled 

in the FREEDOM trial in 213 centers 

worldwide, a subgroup with known risk 

factors (multiple prevalent vertebral fractures, 

aged ≥75 years and/or with a femoral 

neck BMD T-score of ≤–2.5) was analyzed 

post hoc. 7 In all three groups, denosumab 

significantly reduced the risk of fracture 

to a degree consistent with that in low-risk 

patients. Thus, denosumab has a consistent 

antifracture efficacy in patients with varying 

degrees of fracture risk. Interestingly, the 

higher absolute risk observed in the highrisk 

group was associated with the greatest 

denosumab-induced risk reduction. 

ENDOCRINOLOGY 

Another novel antiresorptive approach has 

been to antagonize not the differen tiation 

but the function of osteoclasts through 

inhi bition of cathepsin K, an enzyme utilized 

by osteoclasts to degrade the dense 

col lagen that constitutes most of the bone 

matrix. Following the report of a 2-year 

phase II trial, 8 Eisman et al. 9 reported in 

2011 the results of a 1-year extension study. 

Con tinued treatment of postmenopausal 

women with 50 mg odanacatib (orally once 

a week for 3 years) produced significant 

increases from baseline and from year 2 in 

BMD at both the spine and the hip. Bone 

resorption markers remained suppressed, 

whereas the bone formation marker BALP 

was unchanged from baseline, a feature 

that distinguishes this treatment modality 

from other antiresorptive therapies, including 

bisphosphonates and denosumab (see 

above). Confirming this unique profile of 

cathepsin K inhibition, Eastell et al. 10 showed 

that another inhibitor (ONO-5334), given 

to postmenopausal women orally once daily 

for 12 months, also resulted in significant 

increases in BMD at the lumbar spine, total 

hip and femoral neck. These studies sug gest 

that inhibition of cathepsin K, which does 

not decrease osteoclast differentiation, can 

reduce osteoclast acti vity while maintaining 

the ‘coupling’ to bone formation and osteoblast 

activity, thereby efficiently increasing 

BMD. Interestingly, this approach has a 

less negative effect on bone turnover than 

bisphosphonates or denosumab. 

The year 2011 also saw the first reports 

on a novel and potentially troublesome phenomenon: 

the resolution of drug effects. 8,9 

Whereas most therapeutic fields would not 

expect anything other than a resolution of 

effect upon discontinuation of treatment, 

the osteoporosis field was somewhat caught 

by surprise. This surprise can be explained 

by the fact that, for the past 20 years, we 

have been used to the bisphosphonates, 

a class of drugs which remains bound to 

the skeleton and continues to have therapeutic 

acti vity for several years after cessation 

of treat ment. This characteristic has 

both advantages (nothing happens when 

you stop treat ment) and drawbacks (possible 

long-term adverse effects). A more 

troublesome finding is that the studies on 

discontinuation of treatment of both denosumab 

8 and odanacatib 9 have shown not 

only a resolution of effect—that is, rapid 

reversibility of treatment, which would be 

an advantage over bisphosphonates—but 

also a ‘rebound’ effect. High bone turnover 

activity has been shown to rapidly (within 


ENDOCRINOLOGY 

6–12 months) return the patient’s BMD (at 

least spine and hip) to values found before 

initiation of treatment. Biologically, these 

results illustrate the long-suspected existence 

of a ‘skeletal mechanostat’ whereby 

BMD is determined by the balance of a 

large number of factors intrinsic to each 

individual. Unsurprisingly, if these factors 

remain unchanged, the ‘excess’ bone generated 

by antiresorptive treatments is rapidly 

removed by excessive bone resorption once 

we allow osteoclasts to do their job. Yet, this 

phenomenon will create new challenges for 

osteoporosis treatment, probably calling 

for the combined or sequential use of several 

thera peutic principles. Already, the use of 

bis phosphonates to stabilize bone gains after 

PTH treatment has been suggested. Whether 

a similar resolution of effect will occur 

with other anabolic therapies, in particular 

sclero stin anti bodies, will be an important 

question to answer in the coming years. 

In summary, 2011 has seen significant 

pro gress in the understanding and implementation 

of several new therapeutic options 

for the treatment of osteoporosis, in what 

could be called the postbisphosphonate 

era. Although very promising novel antiresorptive 

and anabolic agents have entered 

or been further assessed in clinical trials, 

showing extraordinary efficacies and promises 

for the future, they will have to be 

tested in the long term to better establish 

their safety relative to bisphosphonates. 

These studies have also uncovered novel 

chal lenges, in particular the resolution of 

drug effects, which will need to be addressed 

in order for novel therapeutic strategies to be 

implemented for osteoporosis. 

Department of Medicine, Harvard Medical 

School, Massachusetts General Hospital, 

Endocrine Unit, 188 Longwood Avenue, Boston, 

MA 02115, USA. 

roland_baron@hms.harvard.edu 



companies: Amgen, Arcarios, Bone Therapeutics, 

Merck, Novartis, Roche. See the article online for full 

details of the relationships. 

1. Cosman, F. et al. Effects of intravenous 

zoledronic acid plus subcutaneous teriparatide 

[rhPTH(1–34)] in postmenopausal 

osteoporosis. J. Bone Miner. Res. 26, 503–511 

(2011). 

2. Balemans, W. et al. Increased bone density in 

sclerosteosis is due to the deficiency of a novel 

secreted protein (SOST). Hum. Mol. Gen. 10, 

537–543 (2001). 

3. Balemans, W. et al. Identification of a 52kb 

deletion downstream of the SOST gene in 

patients with van Buchem disease. J. Med. 

Genet. 39, 91–97 (2002). 

4. Padhi, D. et al. Single-dose, placebo-controlled, 

randomized study of AMG 785, a sclerostin 

monoclonal antibody. J. Bone Miner. Res. 26, 

19–26 (2011). 

5. Eastell, R. et al. Effects of denosumab on bone 

turnover markers in postmenopausal 

osteoporosis. J. Bone Miner. Res. 26, 530–537 

(2011). 

6. Cummings, S. R. et al. Denosumab for 

prevention of fractures in postmenopausal 

women with osteoporosis. N. Engl. J. Med. 361, 

756–765 (2009). 

7. Boonen, S. et al. Treatment with denosumab 

reduces the incidence of new vertebral and hip 

fractures in postmenopausal women at high 

risk. J. Clin. Endocrinol. Metab. 96, 1727–1736 

(2011). 

TYPE 1 DIABETES MELLITUS IN 2011 

Heterogeneity of T1DM raises 

questions for therapy 

Paolo Pozzilli 

Research in 2011 regarding β-cell destruction, early 

immunointervention trials and development of late complications 

in type 1 diabetes mellitus have highlighted the heterogeneity 

of this disease. Patient phenotyping should be performed for the 

implementation of tailored therapies, especially taking into account 

the age at which the disease is diagnosed. 

Pozzilli, P. Nat. Rev. Endocrinol. 8, 78–80 (2012); published online 20 December 2011; 

doi:10.1038/nrendo.2011.228 

Type 1 diabetes mellitus (T1DM) is an autoimmune 

disorder involving the destruction 

of pancreatic β cells. Why T1DM develops is 

still debated, but a role of oxidative stress in 

genetically susceptible individuals has been 

proposed in the past few years. Oxidative 

stress in these individuals might be caused 

by a lack of antioxidant enzymes and/or by 

environ mental triggers such as viral infections, 

and has been linked to β-cell cytotoxicity; 

1,2 however, the role of reactive 

oxygen species (ROS) in the pathogenesis 

of T1DM remains controversial. 

In 2011, Thayer et al. 3 reported the 

required cellular sources of ROS for T1DM 

induction in mice models of T1DM. The 

researchers showed that nonobese, diabetic 

(NOD) mice were protected from T1DM as a 

consequence of macrophage and neutrophil 

depletion. Interestingly, depletion of neutrophils 

alone did not protect or delay the onset 

of the disease. In other experiments, using 

mice with spleno cytes genetically altered 

to prevent the production of ROS, development 

of T1DM was significantly delayed. 

These findings suggest that ROS produced 

by macrophages are critical factors in inducing 

damage to the β cells and that targeting 

8. Bone, H. G. et al. Effects of denosumab 

treatment and discontinuation on bone mineral 

density and bone turnover markers in 

postmenopausal women with low bone mass. 


(2011). 

9. Eisman, J. A. et al. Odanacatib in the 

treatment of postmenopausal women with 

low bone mineral density: three-year 

continued therapy and resolution of effect. 

J. Bone Miner. Res. 26, 242–251 

(2011). 

10. Eastell, R. et al. Safety and efficacy of the 

cathepsin K inhibitor ONO-5334 in 

postmenopausal osteoporosis: the OCEAN 

study. J. Bone Miner. Res. 26, 1303–1312 

(2011). 

this mechanism could be a novel approach 

worth considering for T1DM prevention and 

early treatment. 

The results of two trials published in 

2011 revealed the potential of immunotherapy 

to protect β-cell function in patients 

with recent onset of T1DM. 4,5 Abatacept 

is a drug already in use in the treatment of 

rheumatoid arthritis. This fusion protein 

of cytotoxic T-lymphocyte protein 4 and 


■ Signaling of reactive oxygen species 

appears to be a relevant mechanism for 

the initiation of β-cell autoimmunity by 

T cells in mice 3 

■ Immunointervention trials in patients with 

recent onset of type 1 diabetes mellitus 

did not meet everyone’s expectations 4,5 

■ Poor glycemic control is associated with 

an increased risk of heart failure in adult 

patients with T1DM 8 

■ Protective factors for late complications 

exist in some patients with type 1 

diabetes mellitus, 9 and their 

identification would help prevention 

of retinopathy, neuropathy and 

cardiovascular disease 


immunoglobulin modulates costimulatory 

receptors to prevent full T-cell activation. In a 

multi center, double-blind, random ized controlled 

trial of abatacept, 112 patients with 

recent onset of T1DM received abatacept or 

placebo infusions intravenously on days 1, 

14, 28 and monthly for a total of 27 infusions 

over 2 years. 4 The pri mary outcome was the 

C-peptide response following a mixed meal 

evaluated at 2 years. Abata cept, as compared 

to placebo, increased the adjusted C-peptide 

area under the curve (AUC) by 59%, with a 

difference between the two groups persisting 

through out the trial and with a delay in the 

reduc tion of C-peptide of 9.6 months using 

abata cept. The investigators concluded that 

modulation of T cells with abatacept slowed 

reduction in β-cell function over 2 years; 

however, after the 6-months time point, the 

decrease in β-cell function in the abata cept 

group was parallel to that in the placebo 

group, which suggests that the effect of 

a batacept declined over time. 

The second trial tested the capacity of a 

humanized, anti-CD3 monoclonal anti body 

(teplizumab) to preserve β-cell func tion 

and decrease insulin needs in patients with 

T1DM of recent onset aged 8–35 years. 5 In 

a phase III trial, 516 patients diag nosed with 

T1DM for

ENDOCRINOLOGY 

Department of Endocrinology and Diabetes, 

University Campus Bio‑Medico, Via Álvaro del 

Portillo, 21, 00128 Rome, Italy. 

p.pozzilli@unicampus.it 


The author declares associations with the 

following companies: Andromeda Biotech, 

Bristol-Meyers Squibb, GlaxoSmithKline, Novartis, 

Sanofi-Aventis. See the article online for full details 

of the relationships. 

1. Bottino, R. et al. Response of human islets to 

isolation stress and the effect of antioxidant 

treatment. Diabetes 53, 2559–2568 (2004). 

2. Tran, P. O et al. Adenoviral overexpression of 

the glutamylcysteine ligase catalytic subunit 

protects pancreatic islets against oxidative 



in Nature Reviews Endocrinology. Research Highlights, News & Views, Reviews, 



stress. J. Biol. Chem. 279, 53988–53993 

(2004). 

3. Thayer, T. C, et al. Superoxide production by 

macrophages and T cells is critical for the 

induction of autoreactivity and type 1 diabetes. 

Diabetes 60, 2144–2151 (2011). 

4. Orban, T. et al. Co-stimulation modulation 

with abatacept in patients with recent-onset 

type 1 diabetes: a randomised, double-blind, 

placebo-controlled trial. Lancet 378, 412–419 

(2011). 

5. Sherry, N. et al. Teplizumab for treatment of 

type 1 diabetes (Protégé study): 1-year results 

from a randomised, placebo-controlled trial. 

Lancet 378, 487–497 (2011). 

6. Klinke, D. J. Age-corrected beta cell mass 

following onset of type 1 diabetes mellitus 

correlates with plasma C-peptide in humans. 

PLoS ONE 6, e26873 (2011). 

7. Buzzetti, R. et al.C-peptide response and HLA 

genotypes in subjects with recent-onset type 1 

diabetes after immunotherapy with 

DiaPep277: an exploratory study. Diabetes 60, 

3067–3072 (2011). 

8. Lind, M. et al. Glycaemic control and incidence 

of heart failure in 20,985 patients with type 1 

diabetes: an observational study. Lancet 378, 

140–146 (2011). 

9. Sun, J. K. et al. Protection from retinopathy and 

other complications in patients with type 1 

diabetes of extreme duration: the Joslin 

50-Year Medalist Study. Diabetes Care 34, 

968–974 (2011). 

10. Thomas, M. C, et al. Soluble receptor for AGE 

(RAGE) is a novel independent predictor of allcause 

and cardiovascular mortality in type 1 

diabetes. Diabetologia 54, 2669–2677 

(2011). 


GASTROENTEROLOGY & HEPATOLOGY 

HEPATITIS C IN 2011 

A new standard of care and the race towards 

IFN-free therapy 

Wolf Peter Hofmann and Stefan Zeuzem 

Chronic HCV infection is a leading cause of liver-related morbidity and mortality. In 2011, treatment options for 

patients infected with HCV genotype 1 changed dramatically with the approval of two nonstructural protein 3 

protease inhibitors—boceprevir and telaprevir—by the FDA and the European Medicines Agency. 

Hofmann, W. P. & Zeuzem, S. Nat. Rev. Gastroenterol. Hepatol. 9, 67–68 (2012); published online 20 December 2011; doi:10.1038/nrgastro.2011.249 

In phase III clinical trials, the combination 

of boceprevir or telaprevir with PEG- 

IFN-α–ribavirin has been shown to result 

in increased sustained virological response 

(SVR) rates compared with PEG-IFN-α– 

ribavirin (67–75% and 38–44%, respectively) 

in therapy-naive patients. 1,2 As 

these new triple therapies also resulted in 

increased rapid virological response (RVR; 

undetectable levels of HCV RNA at week 4 

of triple therapy) rates, response-guided 

therapy to shorten the duration of treatment 

from 48 weeks to 24–28 weeks is now 

possible for a large proportion of patients. 

Additional phase III clinical trials showed 

that many patients who did not respond 

RVR and SVR (%) 

100 – 

90 – 

80 – 

70 – 

60 – 

50 – 

40 – 

30 – 

20 – 

10 – 

RVR 

SVR 

0 – 

BMS-790052 + 

BMS-650032 

BMS-790052 + 

BMS-650032 + 

PEG-IFN-α–RBV 

well to previous PEG-IFN-α–ribavirin 

therapies also benefited from re-treatment 

with PEG-IFN-α–ribavirin and boceprevir 

or telaprevir. 3,4 Patients who had previously 

relapsed achieved SVR rates of 69–88% 

when re-treated, and previous partial 

responders showed SVR rates of 40–59%. 

In those who had a previous null response, 

SVR rates following re-treatment were still 

poor (33% for telaprevir). 4 

Despite these encouraging achievements 

for patients infected with HCV genotype 1, 

the low tolerability, particularly for PEG- 

IFN-α, and the emergence of resistant 

variants associated with treatment failure 

of triple therapies that include boce previr 

BMS-790052 + 

BMS-650032 

PSI-7977 PSI-7977 + 

RBV12 

or telaprevir are still major drawbacks. 

Furthermore, current dosing schedules are 

complex and the pill burden is high, which 

might result in suboptimal adherence to 

treatment. Combination therapies with two 

direct-acting antiviral agents (DAAs) that 

have different modes of action, and an alloral 

IFN-free DAA therapy should overcome 

resistance, reduce the incidence of adverse 

events and improve treatment adherence. 

Different substance classes with anti-HCV 

activity include nonstructural protein (NS) 

3 protease inhibitors, NS5A inhibitors, and 

nucleoside inhibitors and non-nucleoside 

inhibitors of the HCV NS5B polymerase. 

Results of several trials of DAA combination 

PSI-7977 + 

RBV12 + 

PEG-IFN-α (4) 

PSI-7977 + 

RBV12 + 


PSI-7977 + 

RBV12 + 


Study 1 Study 2 Study 3 

Figure 1 | The effectiveness of an all-oral IFN-free therapy for patients with HCV has been demonstrated in some study arms of three recent trials. 

Patients in study 1 had HCV genotype 1a or 1b infection and previously a null response to PEG-IFN-α–RBV. 8 These patients received 200 mg of the 

protease inhibitor BMS-650032 twice a day plus 60 mg of the NS5A inhibitor BMS-790052 once a day with or without PEG-IFN-α–RBV for 24 weeks. 

Patients with viral breakthrough during dual therapy received PEG-IFN-α–RBV and achieved SVR thereafter (not shown). Patients in study 2 all had HCV 

genotype 1b and had previously had a null response to PEG-IFN-α–RBV. 9 These patients received 200 mg of the protease inhibitor BMS-650032 twice 

a day and 60 mg of the NS5A inhibitor BMS-790052 once a day for 24 weeks. Patients in study 3 had HCV genotypes 2 or 3 and were treatment 

naive. 10 These patients all received 400 mg of the nucleoside inhibitor PSI-7977 once a day as monotherapy or with RBV for 12 weeks. Three arms 

also received PEG-IFN-α for 4, 8 or 12 weeks. Abbreviations: RBV, ribavirin; RVR, rapid virological response; SVR, sustained virological response. 




■ The newly licensed protease inhibitors 

boceprevir and telaprevir substantially 

increase sustained virological response 

rates in treatment-naive 1,2 patients 

infected with HCV genotype 1 and those 

who failed previous therapy 

■ Several IFN-free regimens that combine 

protease inhibitors and polymerase 

inhibitors with or without ribavirin achieve 

undetectable HCV RNA levels early during 

therapy 5,6 

therapies that had at least one IFN-free treatment 

arm were published in 2011 and open 

the race for an all-oral combination therapy 

for patients with chronic hepatitis C. 

In the SOUND-C1 study, 32 patients who 

were infected with HCV genotype 1 were 

randomly assigned to receive the protease 

inhibitor BI 201335 in combination with one 

of two doses of the non- nucleoside inhibitor 

BI 207127 and ribavirin for 4 weeks, followed 

by PEG-IFN-α– ribavirin and BI 201335 until 

week 24. 5 Only patients without optimal 

initial virologic response received PEG- 

IFN-α–ribavirin until week 48. Patients in 

the high-dose treatment group achieved 

better RVR and SVR rates than those in the 

low-dose treatment group (100% and 94% 

versus 73% and 73%). The all-oral triple 

combination administered for 4 weeks was 

generally well tolerated and did not cause 

serious adverse events. 

In a phase II trial, 46 treatment-naive 

patients infected with HCV genotype 1 were 

assigned to receive one of three regimes: the 

protease inhibitor GS-9256 in combination 

with the non-nucleoside inhibitor tegobuvir 

(dual combination); GS-9256, tegobuvir 

and ribavirin (triple combination); or 

GS-9256, tegobuvir, PEG-IFN-α and ribavirin 

(quadruple combination) for 4 weeks. 6 

All patients received PEG-IFN-α–ribavirin 

thereafter, or immediately if they did not 

respond or had virological breakthrough. 

In the dual, triple and quadruple combination 

therapy arms, RVR rates were 7%, 38% 

and 100%, respectively. The low RVR rate 

in the dual DAA combination was mainly 

attributable to the emergence of resistant 

variants, particularly in patients infected 

with HCV genotype 1a. The addition of 

ribavirin to the DAA combina tion further 

reduced viral levels and decreased viral 

breakthrough. None of the patients receiving 

the quad ruple therapy experienced viral 

plateau or breakthrough during the 4 weeks 

of treatment. The combination of GS-9256 

and tegobuvir was generally well tolerated 

and a transient increase in levels of bilirubin 

was observed in all treatment arms. 

In the ZENITH study, 106 patients were 

randomly assigned to receive telaprevir in 

combination with two different doses of 

the non-nucleoside inhibitor VX-222 either 

as a dual DAA therapy or as a quadruple 

therapy in combination with PEG-IFN-α– 

ribavirin for 12 weeks. 7 Patients received 

PEG-IFN-α–ribavirin for an additional 12 

or 24 weeks, depending on their virological 

results at weeks 2 and 8. The RVR rates in 

the low-dose and high-dose VX-222 dual 

DAA combination arms were 17% and 

59%, respectively, and a significant proportion 

of patients developed virological 

breakthrough. In the quadruple combination 

arms, RVR rates for patients receiving 

low-dose and high-dose VX-222 were 86% 

and 87%, respectively, and no virologic 

breakthrough was observed. The DAA 

combina tion was generally well tolerated. 

In two independent trials from the USA 

and Japan, small cohorts of patients with 

HCV genotype 1 infection who were previous 

null responders were treated with the 

protease inhibitor BMS-650023 in combination 

with the NS5A inhibitor BMS-790052 

with or without PEG-IFN-α–ribavirin 

(Figure 1). 8,9 In the US study, patients with 

HCV genotype 1a and 1b infection who 

received quadruple therapy with PEG- 

IFN-α–ribavirin had a better response than 

those who received dual DAA combination 

therapy. 8 Treatment failure with the 

dual therapy was mainly associated with 

HCV genotype 1a. In the Japanese study, 

10 patients, all infected with HCV genotype 

1b, who had previously not responded 

to therapy completed IFN-free DAA 

combina tion therapy with BMS-650023 and 

BMS-790052 for 24 weeks. 9 HCV RNA was 

undetectable from treatment week 8, and all 

patients achieved SVR. 

In addition, a separate study found that 

100% of patients infected with HCV genotypes 

2 or 3 who were treated with the 

nucleoside inhibitor PSI-7977 plus ribavirin 

for 12 weeks achieved an SVR (Figure 1). 10 

The combination with ribavirin (but not 

PEG-IFN-α) remained necessary, as relapses 

occurred with PSI-7977 monotherapy 

in four of 10 patients. 

A new standard of care is now available 

for patients infected with HCV genotype 1. 

Furthermore, exciting results from several 

clinical trials demonstrate that a high proportion 

of patients can achieve undetectable 

levels of HCV RNA during therapy 

with an all-oral IFN-free combination of 

DAAs. Treatment failure of IFN-free DAA 

combina tions is associated with host factors, 

virus factors and the barrier to resistance of 

different compounds and substance classes. 

In this context, the future role of host- 

targeting antiviral agents such as alis porivir 

(cyclophilin inhibitor) and miravirsen 

(miR-122 inhibitor) must be explored. The 

development of a pan-genotypic and an 

all-oral regimen for patients with chronic 

hepatitis C is rapid and promising. 

POLIKUM Friedenau Berlin, POLIKUM MVZ 

GmbH, Rubensstraβe 119, 12157 Berlin, 

Germany (W. P. Hofmann). Medizinische 

Klinik 1, Klinikum der Johann Wolfgang Goethe- 

Universität, Theodor Stern-Kai 7, Frankfurt am 

Main 60590, Germany (S. Zeuzem). 

Correspondence to: S. Zeuzem 

zeuzem@em.uni-frankfurt.de 


W. P. Hofmann declares associations with the 

following companies: Bristol-Meyers Squibb, Gilead, 

Roche, MSD and Janssen Cilag. S. Zeuzem declares 

associations with the following companies: Abbott, 

Achillion, Boehringer Ingelheim, Bristol-Meyers 

Squib, Gilead, iTherX, Merck, Pharmasset, Roche, 

Santaris, Tibotec and Vertex. See the article online 

for full details of the relationships. 

1. Poordad, F. et al. Boceprevir for untreated 

chronic HCV genotype 1 infection. N. Engl. J. 

Med. 364, 1195–1206 (2011). 

2. Jacobson, I. M. et al. Telaprevir for previously 

untreated chronic hepatitis C virus infection. 

N. Engl. J. Med. 364, 2405–2416 (2011). 

3. Bacon, B. et al. Boceprevir for previously treated 

chronic HCV genotype 1 infection. N. Engl. J. 

Med. 364, 1207–1217 (2011). 

4. Zeuzem, S. et al. Telaprevir for retreatment of 

HCV infection. N. Engl. J. Med. 364, 2417–2428 

(2011). 

5. Zeuzem, S. et al. Efficacy of the protease 

inhibitor BI 201335, polymerase inhibitor 

BI 207127, and ribavirin in patients with chronic 

HCV infection. Gastroenterology 141, 

2047–2055 (2011). 

6. Zeuzem, S. et al. The protease inhibitor GS-9256 

and non-nucleoside polymerase inhibitor 

tegobuvir alone, with RBV or peginterferon plus 

RBV in hepatitis C. Hepatology http:// 

dx.doi.org/10.1002/hep.24744. 

7. Di Bisceglie, A. et al. VX-222 with TVR alone or in 

combination with peginterferon alfa2a and 

ribavirin in treatment-naive patients with chronic 

hepatitis C: ZENITH study interim results 

[abstract]. J. Hepatol. 54, S540 (2011). 

8. Lok, A. S. et al. Quadruple therapy with 

BMS-790052, BMS-650032 and PEG-IFN/RBV 

for 24 weeks results in 100% SVR12 in HCV 

genotype 1 null responders [abstract]. 

J. Hepatol. 54, S536 (2011). 

9. Chayama, K. et al. Dual oral combination therapy 

with the NS5A inhibitor BMS-790052 and the 

NS3 protease inhibitor BMS-650032 achieved 

90% sustained virologic response (SVR12) in 

HCV genotype 1b-infected null responder [LB-4]. 

Hepatology 54 (Suppl. 1), 100A (2011). 

10. Gane, E. et al. Once daily PSI-7977 plus RBV: 

pegylated interferon-ALFA not required for 

complete rapid viral response in treatment-naive 

patients with HCV GT2 or GT3 [abstract 34]. 

Hepatology 54 (Suppl. 1), 377A (2011). 


HEPATOCELLULAR CARCINOMA IN 2011 

Genomics in hepatocellular 

carcinoma—a big step forward 

Ryosuke Tateishi and Masao Omata 

Despite enthusiastic efforts using the latest advanced molecular 

technologies, no specific universal genetic alteration has been found 

in hepatocellular carcinoma (HCC). The application of whole-genome 

sequencing using next-generation sequencing technologies is starting 

to clarify the intraindividual and intratumoral diversity in genomic 

alterations in HCC. A new sequencing era in HCC has begun. 

Tateishi, R. & Omata, M. Nat. Rev. Gastroenterol. Hepatol. 9, 69–70 (2012); published online 10 January 2012; 

doi:10.1038/nrgastro.2011.255 

Primary liver cancer is the fifth most frequently 

diagnosed cancer worldwide in men 

and the seventh in women. 1 Hepatocellular 

carcinoma (HCC) is the predominant histological 

type, accounting for 70–85% of total 

liver cancers. 1 Globally, chronic HBV infection 

is the most prevalent cause of HCC, followed 

by chronic HCV infection. Although 

HCC is a typical example of a virus-related 

cancer, it is also strongly associated with 

certain lifestyle factors. Chronic alcoholism 

is a classic risk factor; obesity is also 

recognized to strongly affect HCC development 

compared with other malignancies. 2 

In either case (virus-related or lifestyle 

factors), it is assumed that accumulated 

DNA damage, caused by long-standing 

necroinflammation and regeneration, has a 

major role in the process of hepatocarcinogenesis. 

Despite enthusiastic efforts using 

the latest advanced molecular technologies, 

no specific universal genetic alteration 

has been found in HCC. However, the 

success of sorafenib, a multikinase inhibitor 

of Raf-1 and B-Raf, has provided proof that 

molecularly targeted agents have a role in 

the treatment of HCC. 3 An understanding 

of the comprehensive picture of mol ecular 

alterations in HCC is now profoundly 

needed (Figure 1). 

The International Cancer Genome 

Consortium (ICGC) is an international 

project aiming to obtain a comprehensive 

description of genomic, transcriptomic 

and epigenomic changes in 50 different 

tumor types and/or subtypes that are of 

clinical and societal importance across the 

globe. Japanese and French researchers 

are investigating virus-related and virusunrelated 

HCC, respectively. A study by 

Totoki et al. 4 is the first report in HCC as 

part of this project. The authors sequenced 

HCV-related HCC and lymphocytes from 

a Japanese male using massively parallel 

sequencing. By comparing tumor and nontumor 

sequences, they identified 11,731 

somatic mutations in the tumor. The prevalence 

of somatic substitutions was substantially 

less in the genic (intronic, noncoding 

exon and coding exon) regions relative to 

the intergenic regions, which suggests that 

negative selection of lethal mutations or 

repair of transcribed regions occurs. Totoki 

et al. 4 also detected 90 somatic substitutions 

and seven small somatic insertions 

and deletions in protein-coding regions, 

including in two well-known tumor suppressor 

genes for HCC (TP53 and AXIN1). 

They found somatic alterations in five 

genes that have previously been reported 

in other cancers but were unknown in 

HCC. Whole-exome sequencing revealed 

47 somatic substitutions. Among the validated 

substitutions, a nonsense substitution 

in TSC1 was not detected by whole-genome 

sequencing as only 13.2% of the tumor 

16 

15 

14 

17 

13 

18 

22 

21 

20 

19 

12 

X 



■ Next-generation high-throughput 

sequencing has enabled the 

comprehensive description of genomic 

alterations throughout the genome at 

extremely high resolution; the first report 

using this technology in hepatocellular 

carcinoma (HCC) from an individual with 

chronic hepatitis C revealed previously 

uncharacterized mutation patterns, 

intra-chromosomal rearrangements and 

genetic heterogeneity within the tumor 4 

■ The first application of genome-wide 

association studies to HCV-related HCC 

has identified new susceptibility loci 6,7 

alleles harbored this substitution, which 

demonstrates the variability of genetic 

alterations among cancer cells. 

Li et al., 5 in the USA, also used wholeexome 

sequencing to determine the 

sequences of approximately 18,000 proteincoding 

genes in the cancers and normal 

tissues of ten individuals with HCV-related 

HCC. They identified 689 potential somatic 

mutations, including 429 non synonymous 

somatic mutations in 411 genes. Five genes 

that were found to be mutated in more than 

one tumor (CTNNB1 in four tumors, TP53 

in three tumors and ARID2, DMXL1 and 

NLP1 in two tumors each) were selected for 

further analysis. Li et al. 5 investigated the 

coding exons of these five genes in 23 additional 

HCV-related HCCs, which revealed 

that CTNNB1, TP53, ARID2, DMXL1 and 

NLRP1 were mutated in eight (24.2%), four 

(12.1%), six (18.2%), two (6.1%) and two 

(6.1%) of the total 33 HCCs, respectively. 

Among these genes, the authors identified 

ARID2 as a novel tumor suppressor gene in 

Y 1 

Outer ring: chromosome ideograms 


2 

6 

3 

5 

4 

Somatic mutations in coding regions 

Blue: substitution 

Red: small deletion 

Orange: small insertion 

Copy number changes 

Red: copy number loss 

Green: copy number gain 

11 

10 

9 8 

7 

Inner circle: chromosomal rearrangements 

Green: inversion 

Red: deletion 

Purple: translocation 

Figure 1 | Whole-genome view of somatically acquired alterations in the liver cancer genome. 

Permission obtained from Nature Publishing Group © Totoki et al. Nat. Genet. 43, 464–469 (2011).


HCC, as mutations were found throughout 

the coding region of this gene, all of 

which were predicted to inactivate protein 

function. They evaluated the prevalence 

of ARID2 mutations in 106 additional 

HCC samples of other etiology; the results 

revealed that ARID2 mutations were more 

common in HCV-related HCC (14%) 

compared with HBV-related HCC (2.0%). 

In addition, the prevalence of TP53 mutations 

was significantly higher in HCC of 

individuals from China than those from 

the USA and Europe. These findings could 

be another proof of principle that etiological 

background and mutation profiles are 

mutually correlated. 

In 2011, two genome-wide association 

studies (GWASs) by Japanese investigators 

reported on genetic susceptibility to HCVrelated 

HCC. Kumar et al. 6 performed a 

GWAS using 432,703 autosomal single 

nucleotide polymorphisms (SNPs) in 721 

individuals with HCV-related HCC and 

2,890 HCV-negative controls of Japanese 

origin. The validation study in 673 patients 

with HCC and 2,596 controls using eight 

candidate SNPs identified a locus in the 

5' flanking region (rs2596542) of the gene 

encoding major histocompatibility complex 

class I polypeptide-related sequence A 

(MICA) protein as strongly associated 

with HCV-related HCC (odds ratio 1.39). 

MICA is a membrane protein that activates 

natural killer cells and CD8 + T cells 

by acting as a ligand for NKG2D. The risk 

allele of rs2596542 was associated with low 

levels of soluble MICA, which were shown 

to be proportional to levels of membranebound 

MICA, which suggests that MICA 

potentially has a suppressive role in HCV 

infection (and thus progression to HCC). 

Miki et al. 7 applied the same technique in 

212 individuals with HCV-related HCC and 

765 individuals with chronic HCV without 

HCC. The validation study in 710 cases 

and 1,625 controls identified one intronic 

SNP in the DEPDC5 gene as associated with 

susceptibility to HCV-related HCC (odds 

ratio 1.75). 

Carcinogenesis is basically a collapse in 

a biological system caused by the random 

accumulation of genomic, transcriptomic 

and epigenomic alterations. Using highthroughput 

sequencing, Totoki et al. 4 

found more than 10,000 mutations in the 

HCC tumor, which suggests that many of 

these are meaningless passenger mutations. 

To find a major player or a driver 

mutation, whole-genome sequencing in 

large sample sets is needed; the ICGC 

intend sample sets of 500 (in fact the study 

group updated its whole-genome data on 

27 HCCs as of July 2011). 8 Increasing the 

number of sample sets will contribute not 

only to finding common genetic alterations 

among indivi duals but also to the 

establishment of molecular classifications 

of cancers. 

GWASs are an undoubtedly powerful 

tool for elucidating genetic susceptibility 

to cancer development. However, the odds 

ratios in both of the studies described here 

were less than two. Given that clinical risk 

factors for HCC are well established by past 

epidemiological studies (for example, it is 

widely recognized that males are at least 

two times more susceptible to HCC than 

females), genetic risk factors revealed by 

GWASs should yield odds ratios much 

higher than two in order to influence daily 

clinical practice. Thus, the 1000 Genomes 

Project, 9 which intends to develop a catalog 

of common human genetic variants with a 

frequency of ≥1% by using next-generation 

sequencing technologies, could have an 

important role. 

Despite difficulties in handling large 

amounts of data, next-generation sequencing 

technologies will lead to revolutionary 

change in biomedical research. We have 

reason to be optimistic; if the major problems 

are associated with limited computing 

resources, according to Moore’s law 

(that is, the number of transistors on a chip 

doubles approximately every 2 years), these 

resources are likely to progress rapidly. A 

new sequencing era in HCC has begun. 

Department of Gastroenterology, Graduate 

School of Medicine, The University of Tokyo, 

7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, 

Japan (R. Tateishi). Yamanashi Prefectural 

Hospital Organization, 1-1-1, Fujimi, Kofu-shi, 

Yamanashi-ken 400-8506, Japan (M. Omata). 

Correspondence to: M. Omata 

momata-tky@umin.ac.jp 

Acknowledgements 

The authors appreciate the advice given by 

Dr Yoshinari Asaoka in preparing the manuscript. 


The authors declare no competing interests. 

1. Jemal, A. et al. Global cancer statistics. CA 

Cancer J. Clin. 61, 69–90 (2011). 

2. Calle, E. E., Rodriguez, C., Walker-Thurmond, K. 

& Thun, M. J. Overweight, obesity, and mortality 

from cancer in a prospectively studied cohort of 

US adults. N. Engl. J. Med. 348, 1625–1638 

(2003). 

3. Llovet, J. M. et al. Sorafenib in advanced 

hepatocellular carcinoma. N. Engl. J. Med. 359, 

378–390 (2008). 

4. Totoki, Y. et al. High-resolution characterization 

of a hepatocellular carcinoma genome. Nat. 

Genet. 43, 464–469 (2011). 

5. Li, M. et al. Inactivating mutations of the 

chromatin remodeling gene ARID2 in 

hepatocellular carcinoma. Nat. Genet. 43, 

828–829 (2011). 

6. Kumar, V. et al. Genome-wide association study 

identifies a susceptibility locus for HCV-induced 

hepatocellular carcinoma. Nat. Genet. 43, 

455–458 (2011). 

7. Miki, D. et al. Variation in the DEPDC5 locus is 

associated with progression to hepatocellular 

carcinoma in chronic hepatitis C virus carriers. 

Nat. Genet. 43, 797–800 (2011). 

8. International Cancer Genome Consortium. 

Dataset Summary. International Cancer 

Genome Consortium [online], http:// 

dcc.icgc.org/pages/summary/ (2011). 

9. 1000 Genomes. About the 1000 Genomes 

Project. 1000 Genomes [online], 

http://1000genomes.org/page.php (2011). 

IBD IN 2011 

Advances in IBD management 

—towards a tailored approach 

Guillaume P. Pineton de Chambrun and William J. Sandborn 

Important advances have been made in the management of IBD in 2011. 

Research has focused on optimizing the currently available therapies and 

taking a more tailored approach to each individual patient. 

Pineton de Chambrun, G. P. & Sandborn, W. J. Nat. Rev. Gastroenterol. Hepatol. 9, 70–72 (2012); 

published online 10 January 2012; doi:10.1038/nrgastro.2011.248 

During the past decade, large genome-wide 

association studies in patients with Crohn’s 

disease or ulcerative colitis have brought 

new insights into IBD patho genesis. 1 

Despite this improved understanding of the 

underlying mechanisms regulating mucosal 

inflammation, most of the newly developed 

targeted therapies for IBD are yet to reach 

clinical practice. Anti-tumor necrosis factor 

(TNF) agents, immuno suppressive drugs 

(thiopurines and methotrexate), steroids 

and mesalazine remain the only therapeutic 

options for patients with IBD. A large 

part of IBD clinical research in 2011 was 


focused on the optimization of currently 

available therapies. 

One important advance in 2011 was an 

extension of the indications for currently 

available IBD drugs. Three anti-TNF agents 

are presently available for Crohn’s disease— 

infliximab, adalimumab and certolizumab 

pegol (only approved in the USA)—whereas 

infliximab is the only approved agent for 

ulcerative colitis. 2 A 2011 phase III trial 3 

evaluated the efficacy of two adalimumab 

dosing regimens in patients with moderateto-severe 

ulcerative colitis. Patients (n = 390) 

were randomly assigned to receive one 

of two adalimumab induction protocols: 

ADA160/80 (adalimumab subcutaneously 

160 mg at week 0, 80 mg at week 2 and 40 mg 

at week 4 and 6); and ADA80/40 (adalimumab 

subcutaneously 80 mg at week 0, 

40 mg at weeks 2, 4 and 6) or placebo. At 

week 8, the rates of clinical remission were 

18.5% and 10% in patients treated with 

ADA160/80 and ADA80/40, compared 

with 9.2% in those on placebo. In the subgroup 

analysis, increased baseline C-reactive 

protein concentrations and body weight 

were associated with reduced remission 

rates at week 8 (especially in the ADA160/80 

group), indicating that some patients might 

require a higher dose of adalimumab to 

induce remission. These data provide 

the basis for extension of adalimumab to 

ulcerative colitis, and raises the possibility 

that treatment optimization (potentially 

through therapeutic drug monitoring) 

could further increase drug efficacy. 

In this context, new research should 

be undertaken to tailor IBD treatment 

to each individual. Research addressing 

the selection of patients and drugs based 

on predefined and validated criteria that 

predict treatment efficacy and the need 

for treatment intensification or even treatment 

discontinuation are required to 

further improve the outcome of patients 

with IBD. Among potential criteria useful 

for treatment decision- making, complete 

mucosal healing has emerged as an important 

surrogate marker of ‘deep remission’ 

in IBD and evidence is accumulating that 

mucosal healing can alter the course of the 

disease when achieved. 4 Indeed, anti-TNF 

agents can induce and maintain mucosal 

healing in patients with IBD, and mucosal 

healing was associated with longer clinical 

remission and fewer disease-related 

hospitalizations in patients with Crohn’s 

disease treated with infliximab. 4 In 2011, 

data from the ACT-1 and ACT-2 studies 

demonstrated the importance of mucosal 


■ Adalimumab, a fully humanized 

recombinant monoclonal antibody 

against tumor necrosis factor, is effective 

for induction of remission in patients 

with moderate-to-severe active ulcerative 

colitis 3 

■ Early achievement of mucosal healing 

in patients with ulcerative colitis treated 

with infliximab decreases the risk of 

colectomy during follow-up 5 

■ Switching to adalimumab for reasons 

of convenience or cost in patients with 

Crohn’s disease in clinical remission on 

maintenance therapy with infliximab is 

not advised 7 

■ In Crohn’s disease, discontinuing 

infliximab in those in remission on 

combination therapy (infliximab and 

thiopurines) might be possible in 

selected patients, but cannot as yet be 

recommended in clinical practice 8 

■ Thiopurines do not increase the risk 

of complications during pregnancy in 

women with IBD 10 

healing as a therapeutic goal in patients with 

ulcerative colitis. 5 Patients with refractory, 

moderate- to-severe active disease (n = 364 

in each study) received intravenous placebo, 

inflix imab 5 mg/kg or infliximab 10 mg/kg 

at weeks 0, 2 and 6 and then every 8 weeks 

until week 46 in ACT-1 and week 22 in 

ACT-2. The 2011 re-analysis of previously 

published data showed that infliximabtreated 

patients with mucosal healing at 

week 8 after treatment were less likely to 

progress to colectomy during the first year 

of follow-up. 5 Thus, early evaluation of a 

‘hard’ end point such as mucosal healing 

during the treatment induction phase could 

be useful to determine which patients need 

treatment intensification, and to decrease 

disease-related complica tions. 

The optimal strategy for inducing and 

maintaining remission for 1 year in Crohn’s 

disease is combination therapy with anti- 

TNF agents and thiopurines. 6 For those 

in clinical remission on anti-TNF maintenance 

therapy, a number of questions exist 

regarding switching between or discontinuing 

these agents. In Crohn’s disease, 

both inflix imab and adalimumab are more 

effective than placebo for the maintenance 

of clinical remission, 7 but prospective 

trials directly comparing the efficacy of 

infliximab and adalimumab are lacking. 

Although switching between these two 

agents is effective in patients with Crohn’s 

disease who previously responded to one 

agent and then lost response, switching in 


patients in clinical remission has not been 

studied. Because adalimumab can be selfadministered, 

patients and physicians might 

wish to consider switching from infliximab 

to adalimumab for convenience or costs. 

The clinical outcome of electively switching 

from infliximab to adalimumab in 

patients with Crohn’s disease who were in 

clinical remission on infliximab maintenance 

therapy was investigated in a 2011 

prospective trial. 7 Patients (n = 73) treated 

with a stable infliximab regimen (infusion 

intervals at least every 6 weeks) for the past 

6 months were randomly assigned to continue 

infliximab (5 mg/kg intravenously) 

at the same interval or to switch to adalimumab 

(80 mg subcutaneously at inclusion, 

then 40 mg every other week). At 

1 year, discontinuation of treatment was 

observed in 10 of 36 (six due to intolerance, 

four due to loss of efficacy) patients 

in the adalimumab group and one patient 

in the infliximab group. Moreover, markedly 

more patients preferred subcutaneous 

adalimumab over intravenous infliximab. 

Nevertheless, within 1 year, almost one in 

three patients who switched to adalimumab 

returned to infliximab therapy to control 

Crohn’s disease. On the basis of this inferior 

clinical outcome, switching should be 

reserved only for those with loss of response 

or intolerance. 

Another important issue is whether, 

and when, to stop treatment with anti- 

TNF agents in patients on maintenance 

therapy who have long-standing remission. 

Indeed, patients and physicians might wish 

to consider discontinuation of treatment 

for a variety of reasons—concerns about 

long-term safety, perceived risk during 

pregnancy and costs. A 2011 prospective 

study 8 investigated the risk of relapse 

after withdrawal of infliximab in patients 

with Crohn’s disease (n = 125 on infliximab 

and anti metabolite combination therapy) 

in long-standing remission. Overall, 52 

relapses occurred in 115 patients who 

stopped inflix imab and continued antimetabolites, 

with an estimated risk of 

relapse over 1 year and 2 years of 43.9% and 

52.2%, respectively. Factors associated with 

low risk of relapse were identified, most corresponding 

to surrogate markers of intestinal 

inflammation (Box 1). Re-treatment 

of relapsing patients with inflix imab was 

generally effective and well tolerated 

when evaluated just before the third infusion. 

Notably, about one-half of selected 

patients who stopped infliximab—those 

receiving combination therapy for at least 



Box 1 | Relapse in Crohn’s disease* 

Risk factors 

■ Corticosteroid use 6–12 months before 

infliximab discontinuation 

■ No previous surgical resection 

■ Male sex 

■ Hemoglobin level ≤145 g/l 

■ Leukocyte count >6 × 109 per l 

■ CDEIS >0 

■ hsCRP level ≥5 mg/l 

■ Infliximab trough level ≥2 mg/l 

■ Fecal calprotectin level ≥300 μg/g 

Clinical relapse rates ‡ 

■ 65 years), with 

thiopurines fairly safe in younger patients 

(

Microbes account for 10-fold more cells 

and 100-fold more genes than those of their 

human host. The information encoded in 

the microbiome supplements that of the 

human genome by provision of trophic, 

metabolic and protective signals to the 

host. Although metagenomic sequencing 

has shown a predominance of two major 

families or phyla in the human gut in 

roughly equal proportions (Firmicutes and 

Bacteroidetes), a report on over 20 newly 

sequenced metagenomes from four countries, 

in combination with previous data, 

demonstrated that variation of the microbiota 

at the species level is not continuous 

and tends to congregate within distinct 

clusters or enterotypes. 1 These enterotypes 

are identifiable by their enrichment 

in Bacterioides (enterotype 1), Prevotella 

(enterotype 2) or Ruminococcus (enterotype 

3) and are known to be unrelated to 

nationality or host characteristics such as 

BMI, age or gender, although their diagnostic 

potential remains to be explored. 

Diet seems to be the main lifestyle or 

environ mental modifier of the microbiota, 

and it is noteworthy that although 

short-term dietary interventions have a 

rapid influence on microbial composition 

in the gut, only long-term diets are associated 

with the microbial enterotypes. For 

example, dietary protein and animal fat 

favors Bacteroides, whereas carbohydrates 

seem to favor Prevotella. 2 

The relationship between diet, microbes 

and the metabolic health of the host, including 

the risk of obesity and diabetes, continues 

to generate intriguing information. 3 

The translation of this information to clinical 

medicine took a step forward in 2011 

with the discovery of a direct link between 

the gut microbiota and the risk of atherosclerosis 

caused by microbial- dependent 

metabolism of dietary phospholipids 

and the generation of pro-atherosclerotic 

metabolites. 4 Three metabolites of the 

dietary lipid phosphatidylcholine were 

identified by a metabolomics approach to 

predict the risk of cardiovascular disease. 

The participation of the microbiota in the 

generation of the metabolites is obligate and 

suggests that a pro biotic or other form of 

dietary manipulation may have prophy lactic 

potential against heart disease. 

Although the microbiota shapes intestinal 

immunity and the metabolic welfare 

of the host, host–microbe interactions 

are bidirectional. The mucosal immune 

system influences the composition and 

pro inflammatory potential of the gut 

Diet 

Antibiotics 

Hygiene 

Urbanization 

Family size 

10 13 

human cells 

+ 

10 14 

microbial cells 

microbiota, and disturb ances of innate 

immunity have been linked with aberrant 

expansion of components of the microbiota 

that have been associated with risk 

of inflammatory and metabolic disease. 

For example, mice lacking Toll-like receptor 

(TLR) 5 develop obesity and metabolic 

syndrome, which seems to be dependent 

on alterations in the microbiota. 5 Other 

models of defective innate immunity have 

been associated with the emergence of a 

‘colitogenic’ microbiota with the capacity to 

transfer colitis to normal recipients and, in 

one report, Koch’s postulates were fulfilled 

in a host-genotype-specific way. 6 

The regulatory mechanisms used by the 

host to maintain compositional equilibrium 

within the microbiota are uncertain, but a 

newly identified molecular pathway highlights 

the pivotal role of intestinal epithelial 

cells. 7 The epithelium contributes to both 

afferent and efferent limbs of the mucosal 

immune response by detecting microbeassociated 

molecular patterns (MAMPs), 

using surface receptors and intra cellular 

sensors, and by responding to danger 

signals with the production of bacteriocides, 

cytokines or chemokines. Intracellular 

inflammasomes are multiprotein complexes 

comprised, in part, of nod-like 

receptors (NLRs), such as NLRP6, and they 

sense endogenous and exogenous stress 

or damage-associated molecular patterns. 

In response to pathogenic components of 

the commensal microbiota, the intestinal 


Mucosal immunity 

Trophic, 

metabolic 

and 

protective 

signals 

Disease risk 

Cardiovascular 

Metabolic 

In�ammatory 

Other 

Repository of bioactive agents 

Metabolome 

(e.g. antimicrobial, anti-in�ammatory, metabolic) 

Figure 1 | Clinical importance of the gut microbiota. The human metabolome is the composite 

product of the human genome and the microbiome, the latter providing trophic, metabolic and 

protective signals to the host that are crucial for development and homeostasis. Host–microbe 

signaling is bidirectional; in susceptible individuals, aberrant host–microbe interactions 

represent a risk factor for disease. Several aspects of a modern lifestyle influence the 

composition of the microbiota, with the most important being diet. Microbe–host signaling, as 

well as microbe–microbe signaling, within the gut represents a rich repository from which 

bioactive agents for drug discovery can be mined. 

epithelium mobilizes the NLRP6 inflammasome, 

triggering a cascade of events that 

includes activation of caspase 1, maturation 

of IL-18, recruitment of γ-interferonproducing 

natural killer cells and T cells 

and enhanced bactericidal activity of local 

macrophages. When NLRP6 is deficient, 

the epithelium fails to respond appropriately 

to pathogens and the composition of 

the commensal bacteria may become colitogenic. 

This provokes epithelial production 


■ The diversity of species within the gut 

microbiota is organized into identifiable 

clusters or enterotypes that are 

correlated with long-term but not 

short-term dietary patterns 1,2 

■ A direct link between the intestinal 

microbiota, dietary phosphatidylcholine 

and risk of atherosclerosis has been 

identified 4 

■ Mechanisms by which the host 

distinguishes harmless commensals 

from pathogens are uncertain, but 

a molecular cascade within enteric 

epithelial cells (triggered by the NLRP6 

inflammasome) could have a role in 

maintaining a balanced composition 

within the microbiota 7 

■ The metabolic diversity within the 

microbiota represents a repository from 

which bioactive agents can be mined, 

as shown with the discovery of an 

antimicrobial bacteriocin with specific 

activity against Clostridium difficile 10 



of the CCL5 chemokine, which recruits 

neutrophils and manifests as IBD. 7 

The identity of the activating trigger for 

the NLRP6 inflammasome in epithelial cells 

is unknown. The trigger might be a damageinduced 

molecular pattern, which is one 

mechanism by which the host could distinguish 

harmless commensals from pathogens, 

both of which express similar molecular patterns 

as ligands for TLRs. However, in some 

instances, the pathogen and commensal 

dichotomy might simply relate to the context 

of their encounter with the immune system. 

Thus, a commensal in the wrong place will 

be treated as a pathogen; likewise, the handling 

of commensals in certain genetically 

susceptible individuals might be similar 

to that of pathogens. Another explanation 

for immunologic discrimination between 

pathogens and commensals could involve 

recognition of symbiotic bacterial molecules 

in a process that favors colonization 

with commensals. 8 An immunomodulatory 

polysaccharide produced by the prominent 

gut commensal, Bacteroides fragilis, has 

been reported to suppress T H 17 effector 

cells by signaling through TLR2 on regulatory 

T cells, thereby enabling the commensal 

to avoid an adverse immune response and 

successfully colonize the host. The response 

to polysaccharide is distinct from that seen 

with other TLR2 ligands that promote clearance 

of pathogens. The immunomodulatory 

properties of polysaccharide also have efficacy 

in an animal model of IBD, confirming 

the potential for mining the microbiota for 

drug discovery (Figure 1). 

Other examples of bacterial-derived 

metabolites with therapeutic potential 

include the production of a soluble protein 

ligand for the epidermal growth factor 

receptor by Lactobacillus rhamnosus GG 

(which attenuates intestinal inflammation 

by inhibiting cytokine-induced apoptosis in 

intestinal epithelial cells), and the discovery 

of an antimicrobial agent with narrow- 

spectrum activity against Clostridium 

difficile. 9,10 The latter was uncovered by an 

extensive screen of fecal colonies for antimicrobial 

producers and resulted in the 

identification of a strain of B. thuringiensis 

that produces a heterodimeric bacteriocin, 

thuricin CD, which has potent activity 

against C. difficile. Using a distal colon 

model, thuricin CD was shown to be as 

effective as vancomycin and metronid azole 

but exhibited a narrower spectrum of activity 

without causing ‘collateral damage’ to the 

dominant phyla within the surrounding 

commensal microbiota. 

What can we expect from this field in the 

immediate future? Microbial enterotypes 

are likely to be refined and correlated with 

human genotypes with respect to disease 

risk, and longitudinal studies will shed light 

on the impact of lifestyle variables over time. 

However, as molecular profiling continues 

apace, studies of the microbiota should be 

complemented with a return to culturebased 

in vitro studies to fulfil the promise 

of mining the microbiota and to understand 

the molecular basis of host–microbe 

interactions in health and disease. 

Department of Medicine, Clinical Sciences 

Building, Cork University Hospital, Wilton, Cork, 

Ireland. 

f.shanahan@ucc.ie 


F. Shanahan is supported, in part, by Science 

Foundation Ireland. 



companies: Alimentary Health Ltd, GlaxoSmithKline, 

Procter & Gamble. See the article online for full 

details of the relationships. 

1. Arumugam, M. et al. Enterotypes of the human 

gut microbiome. Nature 473, 174–180 (2011). 

2. Wu, G. U. et al. Linking long-term dietary 

patterns with gut microbial enterotypes. 

Science 334, 105–108 (2011). 

3. Shanahan, F. & Murphy, E. The hybrid science 

of diet, microbes, and metabolic health. Am. 

J. Clin. Nutr. 94, 1–2 (2011). 

4. Wang, Z. et al. Gut flora metabolism of 

phosphatidylcholine promotes cardiovascular 

disease. Nature 472, 57–63 (2011). 

5. Vijay-Kumar, M. et al. Metabolic syndrome 

and altered gut microbiota in mice lacking 

Toll-like receptor 5. Science 328, 228–231 

(2010). 

6. Bloom, S. M. et al. Commensal Bacteroides 

species induce colitis in 

host-genotype-specific fashion in a mouse 

model of inflammatory bowel disease. Cell 

Host Microbe 9, 390–403 (2011). 

7. Elinav, E. et al. NLRP6 inflammasome 

regulates colonic microbial ecology and risk 

for colitis. Cell 145, 745–757 (2011). 

8. Round, J. L. et al. The Toll-like receptor 2 

pathway establishes colonization by a 

commensal of the human microbiota. Science 

332, 974–977 (2011). 

9. Yan, F. et al. Colon-specific delivery of a 

probiotic-derived soluble protein ameliorates 

intestinal inflammation in mice through an 

EGFR-dependent mechanism. J. Clin. Invest. 

121, 2242–2253 (2011). 

10. Rea, M. C. et al. Effect of broad- and narrowspectrum 

antimicrobials on Clostridium 

difficile and microbial diversity in a model of 

the distal colon. Proc. Natl Acad. Sci. USA 108 

(Suppl. 1), 4639–4644 (2011). 

NEUROGASTROENTEROLOGY IN 2011 

Emerging concepts in 

neurogastroenterology and motility 

Keith A. Sharkey and Gary M. Mawe 

Neurogastroenterology encompasses intrinsic and extrinsic neural 

processes that regulate gut functions, sensation and related behaviors 

such as ingestion. In 2011, key advances were made in understanding 

gut–brain interactions, visceral sensation, serotonin signaling, 

neurogenesis and neuromuscular transmission. 

Sharkey, K. A. & Mawe, G. M. Nat. Rev. Gastroenterol. Hepatol. 9, 74–76 (2012); 

published online 13 December 2011; doi:10.1038/nrgastro.2011.247 

Neural control of the gastrointestinal tract 

in both health and disease is a rapidly 

evolving and intriguing subject area. Key 

advances have been made on several fronts 

in neurogastroenterology in 2011. Here, we 

highlight a breadth of studies that represent 

major milestones in our understanding of 

the effect of nutrients and gut microbiota on 

emotion and food intake; the role of stress 

in visceral hypersensitivity; the concept 

that enteric glia can serve as neuronal precursors; 

and the roles of serotonin signaling 

in the gut. In addition, we discuss the 

identifica tion of a novel class of cells that 

could mediate inhibitory neuromuscular 

signaling in the gastrointestinal tract. 

It is becoming increasingly clear that 

signals arising in the lumen of the gastrointestinal 

tract can lead to changes in emotional 

state and behaviors such as food 

intake. The notion that foods with a high fat 

content are ‘comfort foods’ was substantiated 

this year by MRI studies demon strating 

that intragastric infusion of fatty acid positively 

enhanced emotional states, decreased 

hunger scores and increased neural activity 

in the regions of the brain that process 

emotions. 1 These findings indicate that 


luminal nutrients can have acute effects on 

mood as well as satiety. Evidence indicates 

that endocannabinoid signaling in the gut 

regulates fat consumption. Thus, the capacity 

to regulate fat intake exists within the 

gut, and this process could, in turn, have 

an effect on emotional state and long-term 

energy balance. 

In addition to nutrients, gut–brain 

communication can also be influenced 

by enteric microflora, including resident 

microbes and ingested probiotics. A recent 

study has shown that probiotic bacteria 

influence emotional behavior by modulating 

the subunits of receptors of the neurotransmitter 

γ-aminobutyric acid, and 

attenuate anxiety via activation of vagal 

pathways. 2 Probiotic treatment strategies 

might, therefore, prove to be beneficial in 

stress-related disorders (such as anxiety and 

depression), which are common comorbidities 

of functional and inflammatory 

bowel disorders. 

Although stress is known to potentiate 

visceral pain and discomfort, a lack of 

adequate animal models has meant that 

the mechanisms that underlie this form 

of visceral hypersensitivity have not been 

resolved. Advances in the past year have 

provided insights into peripheral and central 

mechanisms and have helped to explain how 

stress exacerbates visceral pain. Following 

the resolution of infectious colitis in mice, 

induction of stress resulted in exaggerated 

peripheral nociceptive signaling—which is 

analogous to post infectious IBS. 3 The hyperexcitabity 

of primary afferent neurons in this 

model is associated with enhanced expression 

of β-adrenergic and gluco corticoid 

receptors in these cells. Interestingly, the 

effects of stress are mimicked by agonists 

of these receptors, thus providing potential 

new therapeutic targets. In addition to 

changes in primary afferent neurons, stressinduced 

activation of astroglial cells in the 

spinal cord also seems to contribute to visceral 

hypersensitivity through the modulation 

of glutaminergic signaling. 4 These novel 

observations highlight the importance of 

spinal glia and glutamate metabolism in the 

sensation of pain. 

Glia in the brain and gut serve a wide 

array of functions beyond their original 

definition as the ‘glue’ that holds neurons 

together. In the gut, these functions are 

known to include metabolic regulation, 

neurotransmission and support of barrier 

integrity. Two independent studies published 

during the past year provide compelling 

evidence that enteric glia have the 


■ Nutrients and bacteria in the lumen of 

the gut can affect mood and ingestive 

behavior through vagal pathways 1,2 

■ Peripheral and central mechanisms 

contribute to stress-induced visceral 

hypersensitivity 3,4 

■ Enteric glia can give rise to new enteric 

neurons 5,6 

■ Neuronal serotonin protects the integrity 

of the enteric nervous system and 

regulates gastrointestinal motility and 

inflammation 7–9 

■ Fibroblast-like cells mediate inhibitory 

purinergic neuromuscular transmission 10 

potential to give rise to neurons in adult 

gut or in culture under certain restricted 

conditions. Laranjeira and colleagues 5 used 

genetic lineage tracing to confirm previous 

results showing that neurogenesis does 

not seem to occur in the enteric nervous 

system under steady state conditions. This 

observa tion was corroborated by Joseph 

and colleagues 6 who used incorporation 

of a thymidine analogue to investigate 

cell division. Remarkably, after injury to 

the myenteric plexus, glia were shown to 

generate new neurons in vivo. 5 However, 

the conditions under which neurons can 

be replaced seem to be limited to injury to 

the plexus. Gliogenesis was observed both 

in steady-state conditions and in response 

to injury, but the function of new glial cells 

remains to be determined. In culture conditions, 

enteric glia could readily form new 

neurons, which indicates that endogenous 

pre cursors exist within a patient’s own 

bowel and could be used for transplantation 

to replace neurons lost or damaged as 

a result of idiopathic or acquired enteric 

neuropathies. 

Serotonin (5-hydroxytryptamine; 5-HT) 

in the gastrointestinal tract can trigger 

motor, secretory and vasodilator reflexes 

under physiological conditions, and acts 

as a proinflammatory mediator and stimulator 

of emesis, pain and discomfort in 

pathophysiological conditions. Changes 

in serotonin signaling have been reported 

in patients with functional gastrointestinal 

disorders; however, the causative role of 

serotonin in the symptoms of these conditions 

is not yet fully established. A report 

suggests that mucosal serotonin could contribute 

to visceral pain in these individuals. 7 

In patients with IBS, spontaneous serotonin 

release from the mucosa is increased, which 

correlates with the severity of abdominal 

pain. Moreover, biopsy supernatants 


from these individuals activate discharge 

of extrinsic afferent fibers in an ex vivo rat 

preparation, and this response is inhibited 

by granisetron—an antagonist of the 

5-HT 3 receptor. 

The majority of serotonin is synthesized, 

stored and released by entero chromaffin 

cells in the gastrointestinal mucosa; serotonin 

also serves as an enteric neurotransmitter, 

but the physiological role of 

enterochromaffin cell and neuronal serotonin 

signaling has not been fully determined. 

Li and colleagues 8 addressed this 

issue using mice that lack the genes for 

tryptophan hydroxylase 1 or 2 (enzymes 

required for serotonin biosynthesis in 

enterochromaffin cells and neurons, respectively). 

Although mice lacking mucosal 

serotonin did not exhibit a clear phenotype 

with regard to gut function, mice deficient 

in neuronal serotonin exhibited lower neuronal 

density, slower intestinal transit and 

accelerated gastric emptying when compared 

with healthy mice. These findings 

indicate that neuronal serotonin protects 

the integrity of the enteric nervous system 

and contributes to normal gastrointestinal 

motility. Mucosal serotonin can act as a 

proinflammatory mediator, but Tsuchida 

et al. 9 demonstrated that activation of 5-HT 4 

receptors on enteric nerve terminals triggers 

an anti-inflammatory effect. 5-HT 4 

agonists facilitate acetylcholine release, 

which, in turn, can dampen proinflammatory 

cytokine induction via α7 nicotinic 

receptors on macrophages. This finding 

suggests that 5-HT 4 agonists might, by 

inhibiting the inflammatory response and 

promoting propulsive motility, have a beneficial 

effect in certain conditions, such as 

postoperative ileus. 

One of the ongoing controversies in 

neuro gastroenterology over the past decade 

has been the mechanism by which smooth 

muscle cells receive inhibitory purinergic 

signals from enteric motor neurons. These 

signals do not seem to be mediated either 

directly by smooth muscle or indirectly 

by interstitial cells of Cajal because mice 

lacking interstitial cells of Cajal still exhibit 

purinergic inhibitory junction potentials, 

and isolated smooth muscle cells exhibit 

mixed excitatory and inhibitory responses 

to ATP. Kurahashi and colleagues 10 shed 

light on this dilemma in a report demonstrating 

that a novel class of excitable cells 

(referred to as ‘fibroblast-like cells’), which 

express platelet-derived growth factor 

receptor α, exhibit all of the properties necessary 

to detect and transmit puri nergic 



signals from nerve terminals to smooth 

muscle. These interstitial cells should be 

investigated for potential contributions to 

gastrointestinal motor disorders. 

The gastrointestinal dysfunctions that 

fit under the umbrella of neurogastroenterology 

represent a considerable burden 

to society with limited treatment options. 

Continued efforts, such as those highlighted 

here, will provide a better understanding of 

these enigmatic disorders and open new 

avenues for therapies of the future. 

Hotchkiss Brain Institute & Snyder Institute of 

Infection, Immunity and Inflammation, 

Department of Physiology & Pharmacology, 

University of Calgary, AB T2N 4N1, Canada 

(K. A. Sharkey). Department of Anatomy & 

Neurobiology, University of Vermont, Burlington, 

VT 05405, USA (G. M. Mawe). 



in Nature Reviews Gastroenterology & Hepatology. Research Highlights, News & Views, 

Reviews, and Perspectives—you won’t miss a thing! 


Correspondence to: K. A. Sharkey 

ksharkey@ucalgary.ca 



1. Van Oudenhove, L. et al. Fatty acid-induced gutbrain 

signaling attenuates neural and behavioral 

effects of sad emotion in humans. J. Clin. Invest. 

121, 3094–3099 (2011). 

2. Bravo, J. A. et al. Ingestion of Lactobacillus strain 

regulates emotional behavior and central GABA 

receptor expression in a mouse via the vagus 

nerve. Proc. Natl Acad. Sci. USA 108, 

16050–16055 (2011). 

3. Ibeakanma, C. et al. Brain-gut interactions 

increase peripheral nociceptive signaling in mice 

with postinfectious irritable bowel syndrome. 

Gastroenterology 141, 2098–2108 (2011). 

4. Bradesi, S. et al. Role of astrocytes and altered 

regulation of spinal glutamatergic 

neurotransmission in stress-induced visceral 

hyperalgesia in rats. Am. J. Physiol. Gastrointest. 

Liver Physiol. 301, G580–G589 (2011). 

5. Laranjeira, C. et al. Glial cells in the mouse 

enteric nervous system can undergo 

neurogenesis in response to injury. J. Clin. 

Invest. 121, 3412–3424 (2011). 

6. Joseph, N. M. et al. Enteric glia are multipotent 

in culture but primarily form glia in the adult 

rodent gut. J. Clin. Invest. 121, 3398–3411 

(2011). 

7. Cremon, C. et al. Intestinal serotonin release, 

sensory neuron activation, and abdominal pain 

in irritable bowel syndrome. Am. J. 

Gastroenterol. 106, 1290–1298 (2011). 

8. Li, Z. et al. Essential roles of enteric neuronal 

serotonin in gastrointestinal motility and the 

development/survival of enteric dopaminergic 

neurons. J. Neurosci. 31, 8998–9009 (2011). 

9. Tsuchida, Y. et al. Neuronal stimulation with 

5hydroxytryptamine 4 receptor induces antiinflammatory 

actions via α7nACh receptors on 

muscularis macrophages associated with 

postoperative ileus. Gut 60, 638–647 (2011). 

10. Kurahashi, M. et al. A functional role for the 

‘fibroblast-like cells’ in gastrointestinal smooth 

muscles. J. Physiol. 589, 697–710 (2011). 


NEPHROLOGY 

GLOMERULAR DISEASE IN 2011 

New clues to environmental influences 

in glomerular disease 

Peter J. Nelson and Charles E. Alpers 

Research into genetic susceptibilities for proteinuric glomerular diseases has uncovered key pathogenic 

contributions from inheritable defects in podocytes. However, much less is known about environmental factors 

that may initiate or propagate podocyte injury. Seminal reports in 2011 provided new mechanistic insights into 

how this may occur. 

Nelson, P. J. & Alpers, C. E. Nat. Rev. Nephrol. 8, 65–66 (2012); published online 13 December 2011; doi:10.1038/nrneph.2011.214 

Over the past 10 years, numerous high- 

profile studies in forward and reverse genetics 

have mapped several genetic causes for 

proteinuric glomerular diseases. 1 Many 

identified genes encode mutant proteins 

(for example, nephrin, podocin, or TRPC6) 

or variant proteins (for example, APOL1 or 

HLA-DQ) that render podocytes susceptible 

to injury, highlighting the critical contribution 

of podocytes to the glomerular filtration 

barrier (GFB). This research is leading 

towards prog nostic strategies to gauge 

hereditary risk for disease and response to 

treatment in protein uric glomerular diseases. 

The findings have also, however, 

exposed the comparatively little attention 

given to identi fying environmental factors 

that unmask genetic susceptibilities. 

One reason for this imbalance of research 

in gene–environment interactions in 

protein uric glomerular diseases is the lack 

of validated methods to measure and integrate 

effects from the environment. 2 Unlike 

genome-wide association studies, there is a 

lack of techniques for ‘environment-wide’ 

association studies that can identify and 

assign hierarchy to complex exposures from 

diet, the microbiome, xenobiotics, and other 

potential environmental insults that contribute 

to podocyte injury. With this deficiency 

in mind, we briefly review seminal studies 

in proteinuric glomerular diseases published 

in 2011 which reported new pathogenic 

mechanisms that may heighten the focus of 

research in glomerular disease on the role of 

the environment. 

Membranous nephropathy, among 

the most common causes of nephrotic 

syndrome in adults, results from the 

forma tion of glomerular subepithelial 

antibody–antigen immune complexes that 

injure podocytes. Studies have shown that 

antibodies to bovine serum albumin (BSA) 

can induce membranous nephropathy in 

animals, and exposure to BSA is common 

in the human diet. Based on these findings, 

Debiec, Ronco and colleagues hypothesized 

that antibody–BSA immune complexes 

cause secondary membranous nephro pathy 

in humans. 3 The authors found that 11 of 

50 patients with idiopathic membranous 

nephropathy, but only two of 172 controls, 

harbored high-titer serum antibody that 

recognized epitopes in BSA not present in 

human albumin. Seven of the 11 patients 

with membranous nephropathy, but no controls, 

also had higher than normal serum 

levels of BSA, and in four of these patients 

the cationic BSA colocalized with the BSAspecific 

antibody in their subepithelial 

immune complex deposits. 


■ Bovine serum albumin has been identified 

as a dietary cause of membranous 

nephropathy, 3 raising the possibility that 

other dietary antigens may also cause 

membranous nephropathy 

■ Soluble urokinase-type plasminogen 

activator receptor is a likely cause of focal 

segmental glomerulosclerosis that can 

be induced by lipopolysaccharide, 5 and 

probably by other pathogen-associated 

molecular patterns, potentially linking 

podocyte injury to heightened exposure to 

commensal and non-commensal microbes 

■ Overactivation of the podocyte 

mammalian target of rapamycin pathway 

in response to the dysregulated nutrient 

environment of diabetes may contribute to 

the development of diabetic nephropathy 9 

The study by Debiec, Ronco and colleagues 

is a landmark study in that it identi fied a circulating 

exogenous antigenic protein derived 

from dietary exposure that is deposited in 

glomerular walls and serves as a ‘planted’ 

antigen to induce membranous nephropathy. 

The findings of this study raise the possibility 

that other dietary antigens may also 

cause secondary membranous nephropathy. 

Peripheral tolerance to protect podocytes 

and the GFB from dietary antigens filtered 

within the kidney is maintained by the renal 

mononuclear phagocytic system. 4 This 

system may not operate when immunogenic 

dietary antigen is retained at the anionic GFB, 

such as may occur for cationic BSA, leading 

to its recognition by antibody and subsequent 

immune complex formation in situ. 

Without epidemio logic or experimental 

clues, however, the challenge that lies in the 

untargeted discovery of other dietary antigens 

in idiopathic membranous nephropathy 

will be in knowing how best to sample candidates 

and map them to dietary sources and 

potentially to other environmental stimuli. 

Wei, Reiser and colleagues similarly translated 

knowledge gained through animal 

studies to discover that soluble urokinase- 

type plasminogen activator receptor (suPAR) 

is a probable cause of recurrent focal segmental 

glomerulosclerosis (FSGS). 5 The system 

involving suPAR, urokinase-type plasminogen 

activator receptor (uPAR) and urokinase- 

type plasminogen activator (uPA) is an 

innate immune mediator of tissue remodeling 

during inflammation. 6 Wei, Reiser et al. 

showed that endotoxin (lipopolysaccharide), 

produced by commensal bacteria in the gut 

and ubiquitous in the environment, 7 caused 

proteinuria in mice by inducing systemic 


NEPHROLOGY 

release of suPAR, which crossed the GFB 

and activated podocyte β 3 integrin in both 

native uPAR +/+ kidneys and transplanted 

uPAR –/– kidneys. The researchers also 

found that experi mentally sustained secretion 

of suPAR from sites outside the kidney 

induced FSGS. In addition, they found that 

serum suPAR level was significantly elevated 

in patients with primary FSGS (but 

not in those with minimal-change disease 

or membranous nephro pathy) compared 

with levels in healthy people; among those 

with FSGS, serum suPAR levels were highest 

in those who developed recurrent FSGS 

after transplanta tion. In patients in whom 

FSGS recurred, glomerular lesions showed 

activated podocyte β 3 integrin, and suPAR 

removed from serum by plasma pheresis 

correlated with remission of recurrent FSGS. 

The results of this study provide a major 

breakthrough in the study of FSGS on several 

fronts. They identify a long-sought-after circulating 

factor that is causative of recurrent 

FSGS, is a potential biomarker for the development 

of or the risk of development of FSGS, 

and is a new potential therapeutic target for 

treating a disease in which current therapies 

show limited efficacy. Although not emphasized 

in the article, this study also provides 

suggestive evidence that FSGS may be an 

outcome of otherwise ‘clinically silent’ inflammation 

from environ mental pathogens. The 

marked upregulation of suPAR by lipopolysaccharide 

in mice suggests that chronic, 

heightened exposure to lipopolysaccharide 

or other pathogen-associated mol ecular patterns 

(PAMPs) derived from commensal or 

non-commensal microbes might cause elevated 

suPAR in humans, resulting in FSGS 

in susceptible individuals. 8 If found to be 

true, this hypothesis could lead to prophylactic 

strategies that manipulate the microbiome 

to lessen exposure and secondary 

damage to podocytes from these PAMPs. 

Podocytes may also be injured by serving 

as sensors and not simply by being bystanders 

of environmental insults. The mammalian 

target of rapamycin (mTOR) signaling 

pathways are of great interest at present; 

sirolimus (also known as rapamycin), a 

drug that targets these pathways, is clinically 

useful in immune suppression, as an antiproliferative 

agent in cardiac stenting, and 

as a potential therapeutic agent for the treatment 

of renal cancer and polycystic disease. 

More recently it has been shown that mTOR 

pathways control aging in multiple model 

systems. In 2011, the mTOR pathway in 

podocytes emerged as a key molecular sensor 

of the nutrient environment. Godel, Huber 

and colleagues examined gene expression 

in microdissected glomeruli from human 

kidneys with early diabetic nephropathy. 9 

They found marked upregulation of target 

genes of the mTOR pathway, suggesting that 

overactivation of this pathway in response 

to the dys regulated nutrient environment of 

diabetes contributes to the development of 

diabetic nephropathy. 9 To test this hypothesis, 

the authors bred mice haplo insufficient 

for mTORC1 in podocytes, thereby curtailing 

the activity of the mTOR pathway, and then 

induced experimental diabetic nephro pathy 

with streptozotocin. Intriguingly, the mice 

showed significant amelioration of diabetic 

nephropathy, clearly demonstrating that 

podocyte gene–environment interactions 

can drive the progression of diabetic nephropathy, 

and also identifying mTOR pathways 

as a potential thera peutic target to abrogate 

the progression of diabetic nephropathy. 

This selection of studies published in 

2011 highlight three seemingly disparate 

glomerular diseases, each with a different 

pathogenesis, but which together account 

for the majority of cases of nephrotic syndrome 

and end-stage renal disease in adults. 

Each of these studies has identified new and 

compelling mechanisms underlying glomerular 

injury. A common feature of these 

studies is that each also indicates the importance 

of under standing the complex role of 

the environ ment in mediating proteinuric 

glomerular diseases. Although we may continue 

to hope that gene replacement therapy 

can eliminate inheritable disease risks, we 

also need to identify concurrent modifiable 

environ mental factors to protect susceptible 

patients from developing disease. These 

studies are signaling the way forward in 

this quest. 

Division of Nephrology (P. J. Nelson), Division of 

Nephrology and Department of Pathology 

(C. E. Alpers), University of Washington Medical 

Center, 1959 NE Pacific Street, Seattle, 

WA 98195, USA. 

Correspondence to: P. J. Nelson 

nelsonpj@uw.edu 



1. Machuca, E., Benoit, G. & Antignac, C. Genetics 

of nephrotic syndrome: connecting molecular 

genetics to podocyte physiology. Hum. Mol. 

Genet. 18, R185–R194 (2009). 

2. Renz, H. et al. Gene-environment interactions in 

chronic inflammatory disease. Nat. Immunol. 

12, 273–277 (2011). 

3. Debiec, H. et al. Early-childhood membranous 

nephropathy due to cationic bovine serum 

albumin. N. Engl. J. Med. 364, 2101–2110 

(2011). 

4. Nelson, P. J. et al. The renal mononuclear 

phagocytic system. J. Am. Soc. Nephrol. (in 

press). 

5. Wei, C. et al. Circulating urokinase receptor as 

a cause of focal segmental glomerulosclerosis. 

Nat. Med. 17, 952–960 (2011). 

6. Smith, H. W. & Marshall, C. J. Regulation of cell 

signalling by uPAR. Nat. Rev. Mol. Cell Biol. 11, 

23–36 (2010). 

7. Michel, O. Severity of asthma is related to 

endotoxin in house dust. Am. J. Respir. Crit. 

Care Med. 154, 1641–1646 (1996). 

8. Kau, A. L, Ahern, P. P., Griffin, N. W., 

Goodman, A. L. & Gordon, J. I. Human nutrition, 

the gut microbiome and the immune system. 

Nature 474, 327–336 (2011). 

9. Godel, M. et al. Role of mTOR in podocyte 

function and diabetic nephropathy in humans 

and mice. J. Clin. Invest. 121, 2197–2209 

(2011). 

POLYCYSTIC KIDNEY DISEASE IN 2011 

Connecting the dots toward a 

polycystic kidney disease therapy 

Vicente E. Torres and Peter C. Harris 

Understanding the complex interactions between the various pathways 

disrupted in polycystic kidney and liver disease is essential to identify and 

optimize therapies for these disorders. Studies published in the past year 

have demonstrated a functional interaction between the main proteins 

implicated in these diseases and identified novel therapeutic approaches. 

Torres, V. E. & Harris, P. C. Nat. Rev. Nephrol. 8, 66–68 (2012); published online 13 December 2011; 

doi:10.1038/nrneph.2011.196 

The enlarged kidneys and liver character istic 

of polycystic kidney disease (PKD) have for 

centuries attracted attention. Pathologists 

in the 19 th century debated whether cysts 

are develop mental or the result of tubular 

obstruction or excessive epithelial cell 

prolifera tion. Microdissection, electron 

micro scopy and physiology studies carried 

out during the 20 th century showed that cysts 

in patients with autosomal dominant PKD 


(ADPKD) detach from renal tubules and 

grow as blind sacs by a process that requires 

cell prolifera tion, net fluid secretion and 

remodeling of extracellular matrix. After the 

PKD1 and PKD2 genes and their encoded 

proteins, polycystin-1 and polycystin-2, 

were identified in 1994 and 1996, respectively, 

research in this area greatly accelerated. 

In the following years, genes mutated 

in autosomal recessive PKD (PKHD1 encoding 

fibro cystin) and in autosomal dominant 

polycystic liver disease (PRKCSH encoding 

glucosidase 2 subunit β, and SEC63 encoding 

translocation protein SEC63 homolog) 

were identified. Polycystin-1, polycystin-2 

and fibrocystin are membrane glyco proteins, 

whereas glucosidase 2 subunit β and SEC63 

are endoplasmic reticulum resident proteins 

needed for translocation and folding 

of integral membrane proteins and secreted 

proteins. Polycystin-1, polycystin-2 and 

fibrocystin have numerous interacting partners 

and their disruption affects multiple 

signaling pathways. Despite the multi plicity 

of genes and signaling pathways involved in 

PKD, interventions affecting many diverse 

targets have been effective in animal models 

of PKD, which indicates the presence of 

connections between the various pathways. 

Understanding these complex interactions 

will be essential to effectively treat PKD. 

Fedeles et al. used mouse mutants to 

show that the main proteins implicated in 

ADPKD, autosomal recessive PKD and 

autosomal dominant polycystic liver disease 

functionally interact. 1 Loss of gluco sidase 2 

subunit β or SEC63 reduces polycystin-1 

and, to a lesser extent, polycystin-2 expression, 

blocks polycystin-1 trafficking to 

primary cilia, causes renal and hepatic cysts, 

worsens cystic disease in hetero zygous 

Pkd1 +/− and Pkd2 +/− mice and induces 

renal cystogenesis in Pkhd1 del4/del4 mice. 

Transgenic overexpression of poly cystin-1, 

but not polycystin- 2, rescues the renal and 

hepatic pheno type of tissue- selective Prkcshknockout 

or Sec63-knockout mice and 

the renal phenotype of Pkhd1 del4/del4 mice. 

Polycystin-1 is the rate-limiting component 

in the polycystin-1/poly cystin-2 complex as 

its level of expression determines the severity 

of the cystic pheno type, but some functional 

polycystin-2 is essential for polycystin-1 

to exert this effect. Immunocytochemical 

analysis revealed that the collecting duct is 

the segment most susceptible to the cystogenic 

effect of reduced polycystin-1 dosage. 

Proteasome inhibition increases poly cystin-1 

levels and attenuates cystic disease in Prkcshknockout 

models, thus offering a conceptual 


■ The main proteins implicated in polycystic 

kidney disease (PKD)—polycystin-1, 

polycystin-2 and fibrocystin—and in 

autosomal dominant polycystic liver 

disease (glucosidase 2 subunit β and 

SEC63) functionally interact 1 

■ The vasopressin V2 receptor antagonist, 

tolvaptan, inhibits cystogenesis in vitro, 2 

and reduced the volume of polycystic 

kidneys after 1 week of treatment, and 

slowed the growth of polycystic kidneys 

in a 3-year, open-label study of patients 

with PKD 3 

■ Two insulin-sensitizing drugs used to 

treat type 2 diabetes mellitus, metformin 

and a peroxisome proliferator-activated 

receptor-γ agonist, inhibit cyst growth in 

rodent models of PKD by different and 

possibly complementary mechanisms 4–6 

■ Macrophage infiltration contributes to the 

proliferation of cyst-lining cells and PKD 

progression 7 

■ STAT3, a transcription factor that is 

essential during development but 

dispensable postnatally, is a novel 

therapeutic target in PKD 8–10 

therapeutic approach to auto somal dominant 

polycystic liver disease and possibly ADPKD. 

The central role of cyclic AMP in PKD, 

and the ability to hormonally modulate 

cyclic AMP in a cell-specific manner, 

enables targeting of an important cystogenic 

pathway with relative safety. Among 

hormonal systems that affect renal cyclic 

AMP is the vasopressin–V2 receptor axis. 

This target is attractive because V2 receptors 

are mostly restricted to the thick 

ascending limb and collecting ducts, which 

are main sites of cystogenesis where vasopressin 

is the major agonist of cyclic AMP. 

These sites are continuously subjected to 

tonic vaso pressin action. Circulating vasopressin 

levels are increased in ADPKD and 

V2 receptors are overexpressed in polycystic 

kidneys. Pharmacological and genetic 

inhibition of vasopressin or V2 receptor 

expression has been shown to be effective 

in rodents. Reif et al. examined the effects of 

tolvaptan on human ADPKD cyst epithelial 

cells. 2 Low concentrations inhibited vasopressin-induced 

cyclic AMP production, 

cell prolifera tion, chloride secretion and cyst 

growth in collagen matrices. Other analyses 

showed that tolvaptan administration for 

1 week reduced total kidney volume by 3.1% 

in patients with ADPKD, and that 3 years of 

tolvaptan therapy reduced kidney growth 

by 70% compared to historical controls 

(1.7% versus 5.8% increase per year, respectively). 

3 Changes in kidney volume and in 

NEPHROLOGY 

estimated glomerular filtration rate were 

significantly and negatively correlated. This 

finding supports the use of kidney volume 

as a biomarker to monitor ADPKD progression. 

Further evaluation of tolvaptan for the 

treatment of patients with ADPKD awaits the 

conclusion of a randomized, double-blind 

clinical trial (NCT00428948) in 2012. 

Metformin and peroxisome proliferatoractivated 

receptor (PPAR)-γ agonists are 

widely used to treat type 2 diabetes melli tus. 

Takiar et al. found that metformin stimulates 

the energy-sensing molecule AMP-activated 

protein kinase (AMPK), inhibits the activities 

of AMPK-dependent cystic fibrosis transmembrane 

conductance regulator (CFTR) 

and mammalian target of rapamycin in 

Madin–Darby canine kidney renal epithelial 

cells, and attenuates cyclic AMP-dependent 

growth of Madin–Darby canine kidney cysts 

in collagen matrices and of cysts in metanephric 

organ explants, and cystogenesis in 

constitutive and inducible Pkd1-knockout 

mice. 4 Yoshihara et al. and Blazer-Yost et al. 

found that the PPAR-γ agonist pioglitazone 

inhibits renal and hepatic cystogenesis in 

PCK rats by possibly complementary mechanisms 

through the inactivation of mitogen- 

activated protein kinase 3 and mammalian 

target of rapa mycin, 5 and inhibition of CFTR 

synthesis and cyclic AMP-activated chloride 

secretion. 6 Because metformin and PPAR-γ 

agonists exert salutary effects by affecting the 

same pathways through different mechanisms 

(such as phosphoryla tion and inhibition of 

CFTR by metformin and inhibi tion of CFTR 

synthesis by pioglitazone), clinical trials of 

metformin and PPAR-γ agonist combinations 

in early ADPKD should be considered 

to exploit their possible synergism. 

Evidence accumulated over the past 

two decades points to the importance of 

inflamma tion in PKD. Karihaloo et al. 

hypothesized that macrophage infiltration 

contributes to the proliferation of cyst-lining 

cells and PKD progression. 7 This premise 

was based on work showing that macrophages 

homing to the kidney after ischemia– 

reperfusion undergo a transition from 

classically activated, pro inflammatory cells 

to alternatively activated cells that promote 

epithelial cell proliferation. The investigators 

found that Pkd1-null cells secrete 

large amounts of the macrophage chemoattractant 

C-C motif chemokine 2 (also 

known as monocyte chemotactic protein 1) 

and C-X-C motif chemokine 16. Kidneys 

from conditional Pkd1-knockout mice 

and the Pkd2 WS25/– mouse model of PKD2 

exhibit a 10-fold increase in the number of 


NEPHROLOGY 

macrophages (most with an alternatively 

activated phenotype and aligned along cyst 

walls). Macrophage depletion by intraperitoneal 

liposomal clodronate administration 

inhibits epi thelial cell proliferation and 

cyst growth and improves renal function. 7 

How the loss of polycystin expression leads 

to increased cytokine production remains to 

be determined. Approaches that inhibit the 

expression or action of homing and proliferation 

signals provide novel strategies for 

treating PKD. 

Three studies have shown marked 

upregula tion of the signal transducer and 

transcription activator (STAT)3 in patients 

with ADPKD and in rodent PKD models. 8–10 

In the STAT3 signaling pathway, activation of 

various cell surface growth factor receptors 

and cytokine receptors induces specific tyrosine 

phosphorylation of the receptors, which 

creates docking sites for latent cytoplasmic 

STAT3. STAT3 is then phosphorylated at 

tyrosine 705 by intrinsic tyrosine kinase activity 

of the activated growth factor receptors or 

by cytokine receptor-associated Janus kinase. 

The trigger for phosphorylation and activation 

of STAT3 in PKD is uncertain. Talbot 

et al. showed that phosphorylated STAT3 

is highly expressed in cyst-lining cells and 

normal- appearing tubules and inter stitial 

cells in proximity to cysts. 8 This finding suggests 

that diffusible factors such as cytokines 

and growth factors are involved in the activation 

of STAT3. Phosphorylated STAT3 homodimers 

translocate to the nucleus and bind 

to promoter elements of genes that regulate 

cell differentiation, proliferation, apoptosis 

and angiogenesis. Because STAT3 is critical 

during development (deletion of STAT3 

leads to embryonic lethality), but is dispensable 

postnatally in conditional knockouts, 

targeting STAT3 might be well tolerated in 

patients with PKD. Takakura et al. screened 

a small-molecule library using a cell-based 

functional assay and found that pyrimethamine, 

a drug used to treat malaria and 

toxoplasmosis, inhibits STAT3 signaling. 9 

Pyrimethamine and S3I-201, an inhibitor 

of STAT3 homodimer complex formation, 

suppressed epithelial cell proliferation and 

cystogenesis in an inducible Pkd1-knockout 

mouse model without toxic effects. In another 

study, Leonhard et al. found that curcumin, 

a compound with anti-inflammatory and 

antiproliferative properties, reduced STAT3 

activation, attenuated cell proliferation 

and cysto genesis and delayed renal failure 

from 105 to 119 days in an inducible Pkd1knockout 

model. 10 As curcumin has poor 

bioavailability, however, novel analogues with 

improved pharmacological profiles might be 

more effective than curcumin itself. 

In summary, insights into the complex 

network of signaling pathways disrupted in 

PKD have increasingly led to the identification 

of potential therapies, some of which are 

currently used for other indications. Those 

compounds best supported by preclinical 

studies and with the desired pharmacological 

profile should be prioritized for 

clinical trials. 

Division of Nephrology and Hypertension, Mayo 

Clinic College of Medicine, 200 First Street SW, 

Rochester, MN 55905, USA (V. E. Torres, 

P. C. Harris). 

Correspondence to: V. E. Torres 

torres.vicente@mayo.edu 


V. E. Torres and P. C. Harris are supported by the NIH 

grant DK090728. 


V. E. Torres declares an association with the 

following company: Otsuka Pharmaceuticals. See 

the article online for full details of the relationship. 

P. C. Harris declares no competing interests. 

1. Fedeles, S. V. et al. A genetic interaction 

network of five genes for human polycystic 

kidney and liver diseases defines polycystin-1 

as the central determinant of cyst formation. 

Nat. Genet. 43, 639–647 (2011). 

2. Reif, G. A. et al. Tolvaptan inhibits ERKdependent 

cell proliferation, Cl – secretion, and 

in vitro cyst growth of human ADPKD cells 

stimulated by vasopressin. Am. J. Physiol. Renal 

Physiol. 301, F1005–F1013 (2011). 

3. Higashihara, E. et al. for the TEMPOFormula 

and 156-05-002 Study Investigators. Tolvaptan 

in autosomal dominant polycystic kidney 

disease: three years’ experience. Clin. J. Am. 

Soc. Nephrol. 6, 2499–2507 (2011). 

4. Takiar, V. et al. Activating AMP-activated protein 

kinase (AMPK) slows renal cystogenesis. Proc. 

Natl Acad. Sci. USA 108, 2462–2467 (2011). 

5. Yoshihara, D. et al. PPAR-γ agonist ameliorates 

kidney and liver disease in an orthologous rat 

model of human autosomal recessive 

polycystic kidney disease. Am. J. Physiol. Renal 

Physiol. 300, F465–F474 (2011). 

6. Blazer-Yost, B. L. et al. Pioglitazone attenuates 

cystic burden in the PCK rodent model of 

polycystic kidney disease. PPAR Res. 2010, 

274376 (2010). 

7. Karihaloo, A. et al. Macrophages promote cyst 

growth in polycystic kidney disease. J. Am. Soc. 

Nephrol. 22, 1809–1814 (2011). 

8. Talbot, J. J. et al. Polycystin-1 regulates STAT 

activity by a dual mechanism. Proc. Natl Acad. 

Sci. USA 108, 7985–7990 (2011). 

9. Takakura, A. et al. Pyrimethamine inhibits adult 

polycystic kidney disease by modulating STAT 

signaling pathways. Hum. Mol. Genet. 20, 

4143–4154 (2011). 

10. Leonhard, W. N. et al. Curcumin inhibits 

cystogenesis by simultaneous interference of 

multiple signaling pathways: in vivo evidence 

from a Pkd1-deletion model. Am. J. Physiol. 

Renal Physiol. 300, F1193–F1202 (2011). 

ACUTE KIDNEY INJURY IN 2011 

Biomarkers are transforming our 

understanding of AKI 

Lakhmir S. Chawla and John A. Kellum 

Acute kidney injury (AKI) is a syndrome of decreased renal function that is 

associated with an increased risk of death. Studies from 2011, particularly 

in the field of AKI biomarkers, have provided important insights into the 

diagnosis, prognosis, and treatment of AKI. These advances are now being 

brought to the bedside to improve diagnosis and treatment of AKI. 

Chawla, L. S. & Kellum, J. A. Nat. Rev. Nephrol. 8, 68–70 (2012); published online 17 January 2012; 

doi:10.1038/nrneph.2011.216 

Over 2 million people are afflicted by 

acute kidney injury (AKI) worldwide. 1 

AKI is a serious complication of acute 

illness, typically occurring as a result of 

underlying conditions such as sepsis, and 

is independently associated with death. It 

has become increasingly clear that AKI is 

associated with the development of endstage 

renal disease (ESRD) and chronic 

kidney disease (CKD). 2,3 Individuals fortunate 

enough to survive a severe episode 

of AKI are therefore at risk of develop ing 

CKD-related disease. 

Our understanding of AKI has advanced 

over the past decade, with a unified definition 

and standard criteria for staging, a 

quantification of renal replacement therapy 

(RRT) dosing, and the emergence of biomarkers 

related to AKI. In 2011, multiple 

studies were published that improve our 

understanding of AKI through the use of 

various biomarkers. Perhaps the most illuminating 

study published in 2011 was one by 

Paragas et al. that examined the expression 

of neutrophil-related gelatinase lipocalin 

(NGAL) using a luciferase reporter assay. 4 


Although NGAL has been shown in multiple 

large cohort studies to be a biomarker for 

early AKI diagnosis and for AKI prognosis, 5 

NGAL is expressed in multi ple organs and 

is thus not kidney specific. Understanding 

how non-kidney sources of NGAL impact 

the urinary NGAL signal and indeed 

establishing the sources of NGAL in AKI 

is essential. Paragas and colleagues 4 conducted 

their novel experiment by creating 

a reporter mouse for NGAL. They inserted 

a double-fusion reporter gene that encoded 

luciferase-2 and mCherry (Luc2-mC) in 

the locus for NGAL (lcn-2). In so doing, the 

investigators could assess the endogenous 

NGAL message in real time and assess in 

which organs the message was being transcribed. 

In separate experiments, mice were 

subjected to unilateral renal ischemia, bilateral 

renal ischemia or nephrotoxic injury 

with cisplatin. In addition, the investigators 

tested whether NGAL-Luc2-mC was activated 

in pre-renal azotemia and ascertained 

the segments of the nephron responsible 

for urinary NGAL (uNGAL) production in 

AKI. The investi gators determined that the 

principal or exclusive source of uNGAL was 

the thick ascending limb and the collecting 

ducts of the nephron. In addition, in the prerenal 

azotemia model, serum creatinine level 

rose, but NGAL-Luc2-mC was not activated 

and no increase in uNGAL level occurred. 

These data show that uNGAL is an appropriate 

kidney-injury-specific biomarker 

despite not being exclusively expressed in 

the kidney. 

Another study involving NGAL displayed 

the range of methods by which AKI 

biomarkers can assist clinicians caring for 

patients with AKI. NGAL has been primarily 

thought of as a biomarker for the early 

diagnosis of AKI, 5 but utility of this biomarker 

and others may be much broader. 

Using a large multicenter cohort of patients 

with community-acquired pneumonia, 

Srisawat and colleagues 6 examined plasma 

of patients on the first day they experienced 

severe AKI (defined as RIFLE-F by the Risk, 

Injury, Failure, Loss and ESRD (RIFLE) criteria). 

In this study, recovery was defined 

as being alive and neither requiring RRT 

during hospitalization nor having a persistent 

RIFLE-F classification at hospital 

discharge. The investigators found that 

elevated plasma NGAL (pNGAL) levels 

were associated with renal non-recovery. 

Although the absolute predictive value of 

pNGAL alone was only fair (area under 

the receiver operating characteristic curve 

0.74), the reclassification of risk of not 


■ The source of urinary neutrophil-related 

gelatinase lipocalin (NGAL) seems to be 

nearly exclusively from the renal tubule 

and does not seem to be released during 

pre-renal azotemia in healthy animals 4 

■ Plasma NGAL level helps predict which 

patients with severe acute kidney injury 

(AKI) will recover renal function 6 

■ Urine output remains an important 

‘biomarker’ of AKI, and predicts death 

even in the absence of a rise in serum 

creatinine level 7 

■ Micro RNAs are a new class of AKI 

biomarkers that may prove to be 

important new tools in the diagnosis and 

treatment of AKI 8 

recovering renal function was increased 

by 17%. These data are most notable for 

two reasons. First, because AKI can cause 

CKD and ESRD, decisions regarding longterm 

care (for example, use of dialysis, 

vascular access, and follow-up) are often 

made in a piecemeal approach. If objective 

metrics coupled with clinical assessment 

can improve prognostic accuracy, a 

better informed decision can be made for 

survivors of AKI. Second, the association 

between pNGAL and renal non-recovery 

suggests that renal injury is ongoing, and 

even if a patient is under going dialysis, 

thera pies directed at mitiga ting ongoing 

injury may have a role in AKI treatment. 

‘‘ ...some existing biomarkers 

such as NGAL will begin to shape 

clinical practice... 

Within the advancing field of AKI, the 

oldest known biomarker is urine output. The 

precise utility of oliguria has been controversial, 

and within the Acute Kidney Injury 

Network (AKIN) staging system, there has 

been discussion on the precise definition of 

oliguria over time (for example, consecutive 

hours of oliguria versus average urine 

output over a period of time). To further 

the understanding, Macedo and colleagues7 ’’ 

utilized high-fidelity urimeters to compare 

various definitions of oliguria in critically 

ill patients. In their study, 317 patients 

had speciali zed high-accuracy urimeters 

placed on their urinary catheters in order to 

measure their urine output hourly. Serum 

creatinine was measured every 12 h, and 

definitions of AKI based on urine output 

were compared with those based on serum 

creatinine. Urine output was classified in 

NEPHROLOGY 

three ways: consecutive hours of oliguria 

(oligo6-cons), an average amount of oliguria 

over a fixed block of time (

NEPHROLOGY 

Also in 2011, investigators sought new 

AKI biomarkers that are more directly 

related to the injury itself. Munshi and 

colleagues 10 reported a study where potential 

biomarker candidates were chosen 

from urinary excretion of injury-induced 

mRNAs. The investigators posited that the 

resulting proteins of these mRNAs might 

be good AKI biomarkers and may offer 

pathogenic information in addition to 

diag nostic information. Munshi et al. quantified 

the urinary excretion of the mRNAs 

for one of these candi date proteins, monocyte 

chemo attractant protein-1 (MCP-1). 

The investi gators conducted multiple preclinical 

studies wherein various forms of 

AKI were induced and MCP-1 was compared 

with a known representative AKI 

biomarker, NGAL. In the models of AKI, 

MCP-1 protein and mRNA levels increased 

more than corresponding increases in 

NGAL. Uremia, without kidney injury, 

induced the NGAL gene, but not MCP-1, 

which suggests that MCP-1 may be more 

specific for AKI. These findings were 

tested in a candidate cohort of Acute 

Physiology and Chronic Health Evaluation 

(APACHE)-II-matched critically ill 

patients with and without AKI. In these 

patients, MCP-1 levels were significantly 

higher in those with AKI. 

In our view, these studies advanced 

the field in 2011 and collectively provide 

important information on the current state 

of medi cine pertaining to AKI as well as 

suggesting future directions. We believe 

that some existing biomarkers such as 

NGAL will begin to shape clinical practice 

while new biomarkers will continue to be 

discovered. This ongoing process of new 

discovery and reinvention of existing tools 

(including those as primitive as urine flow) 

will advance the field further and we will 

eventually emerge with a set of tools that 

will not only help us diagnose AKI, but will 

also help us determine its cause, monitor its 

course and predict response to therapy. We 

eagerly await this bright future. 

Department of Anesthesiology and Critical Care 

Medicine, George Washington University 

Hospital, 900 23 rd Street, NW Room G‑105, 

Washington DC 20037, USA (L. S. Chawla). 

604 Scaife Hall, Department of Critical Care 

Medicine, University of Pittsburgh, 

3550 Terrace Street, Pittsburgh, PA 15261, 

USA (J. A. Kellum). 

Correspondence to: J. A. Kellum 

kellumja@ccm.upmc.edu 


L. S. Chawla declares associations with the following 

companies: Abbott, Alere, Astute Medical. 

J. A. Kellum declares associations with the following 

companies: Abbott, Alere, Astute Medical, Roche. 

See the article online for full details of the 

relationships. 

1. Hoste, E. A. et al. Epidemiology of acute kidney 

injury. Contrib. Nephrol. 165, 1–8 (2010). 

2. Chawla, L. S., Amdur, R. L., Amodeo, S., 

Kimmel, P. L. & Palant, C. E. The severity of 

acute kidney injury predicts progression to 

chronic kidney disease. Kidney Int. 79, 

1361–1369 (2011). 

3. Ishani, A. et al. The magnitude of acute serum 

creatinine increase after cardiac surgery and 

the risk of chronic kidney disease, progression 

of kidney disease, and death. Arch. Intern. Med. 

171, 226–233 (2011). 

4. Paragas, N. et al. The Ngal reporter mouse 

detects the response of the kidney to injury in 

real time. Nat. Med. 17, 216–222 (2011). 

5. Shemin, D. & Dworkin, L. D. Neutrophil 

gelatinase-associated lipocalin (NGAL) as a 

biomarker for early acute kidney injury. Crit. 

Care Clin. 27, 379–389 (2011). 

6. Srisawat, N. et al. Plasma neutrophil gelatinaseassociated 

lipocalin predicts recovery from 

acute kidney injury following community-acquired 

pneumonia. Kidney Int. 80, 545–552 (2011). 

7. Macedo, E., Malhotra, R., Bouchard, J., 

Wynn, S. K. & Mehta, R. L. Oliguria is an early 

predictor of higher mortality in critically ill 

patients. Kidney Int. 80, 760–767 (2011). 

8. Lorenzen, J. M. et al. Circulating miR-210 

predicts survival in critically ill patients with 

acute kidney injury. Clin. J. Am. Soc. Nephrol. 6, 

1540–1546 (2011). 

9. Fasanaro, P. et al. MicroRNA-210 modulates 

endothelial cell response to hypoxia and 

inhibits the receptor tyrosine kinase ligand 

Ephrin-A3. J. Biol. Chem. 283, 15878–15883 

(2008). 

10. Munshi, R. et al. MCP-1 gene activation marks 

acute kidney injury. J. Am. Soc. Nephrol. 22, 

165–175 (2011). 

NONDIALYSIS CHRONIC KIDNEY DISEASE IN 2011 

Progression, prediction, 

populations and possibilities 

Adeera Levin 

In 2011, studies of chronic kidney disease (CKD) were published in 

abundance. The articles selected here represent the growing appreciation 

of the importance of CKD as a modifier of outcomes, breakthroughs in 

understanding the pathobiology and genetics of specific conditions, and 

clinical trials of treatment strategies that offer hope to patients with CKD. 

Levin, A. Nat. Rev. Nephrol. 8, 70–72 (2012); published online 6 December 2011; 

doi:10.1038/nrneph.2011.195 

In 2011, almost a decade after the initial 

publication that described a new system 

of evaluation, classification, and definition 

of chronic kidney disease (CKD), this 

condition has become of mainstream interest. 

Articles published in 2011 reflect an 

increase in sophistication of analysis, collaboration 

and real attempts at understanding 

the impact of CKD on individuals and 

health-care systems, the importance of predicting 

disease progression, and, perhaps 

most crucially, the effect of specific therapies 

on outcomes such as cardio vascular 

disease. Selecting the most influential 

papers of 2011 is subject to bias and perspectives 

of the reviewer, but the selection 

here represents the spectrum of studies that 

I believe will influence thinking and practice 

for the next decade. 

Although controversies regarding the 

identification and definition of CKD in the 

general population still exist, Peralta and 

colleagues determined that the addition of 

cystatin C to traditional measures of kidney 

function (creatinine and albumin uria) 

better identifies individuals with ‘true’ CKD 

and those who are likely to progress to endstage 

renal disease (ESRD) than using a 

one-marker or two-marker approach. 1 Much 

controversy surrounding CKD staging has 

related to individuals with higher values of 

estimated glomerular filtration rate (eGFR). 

The study by Peralta et al., which used eGFR 

derived from cystatin C in a general population 

cohort within the REGARDS study, 

confirms that this additional biomarker can 

reliably identify those at high risk of adverse 

events (death, cardiovascular disease, or 

renal replacement therapy). This finding is 

extremely important for the large group of 

patients who have been identified as having 

milder stages of CKD, but for whom outcomes 

are uncertain. Peralta et al. demonstrate 

that knowledge of cystatin C values, 

used in an eGFR equation, will reclassify 

individuals and distinguish important prognostic 

differences (a threefold increased risk 

of death and fourfold increased risk of ESRD 

in this study). This simple observation could 

profoundly affect patients and care providers 


with respect to care-plan modification. 

Confirmation that this simple test helps 

to appropriately reclassify these patients 

is important. Further studies will facilitate 

our understanding. 

Variability in outcomes between ethnic 

groups and within CKD populations with 

similar diseases, has been another source 

of confusion over the past decades. Two 

important breakthroughs were made in 

2011 with respect to genetic determinants 

of kidney disease. Firstly, the importance 

of the apolipoprotein L1 (APOL1) gene in 

predicting any form of progressive CKD in 

African Americans, 2 will have a profound 

impact on clinical care (by suggesting alternative 

treatment), familial donation strategies 

and our understanding of progressive 

disease in this vulnerable population. 

Secondly, in another study, the finding that 

soluble urokinase-type plasminogen activator 

receptor (suPAR) is an important propagator 

of focal segmental glomerulosclerosis 

(FSGS), given its ability to activate podocyte 

β2 integrin, provides new insights into this 

condition. 3 In an elegant set of experiments, 

Wei et al. demonstrated the importance of 

elevated levels of suPAR in patients with 

FSGS, and found that lowering of suPAR 

levels with plasmapheresis led to remission 

of disease. 3 Using a series of mouse models, 

Wei and collaborators clearly identified a 

relationship between suPAR and podocyte 

damage. Although the reason for the elevation 

in suPAR levels remains to be determined, 

the fact that not all patients with 

FSGS have high levels of this protein further 

confirms that FSGS is a response to injury 

rather than a specific disease. Improving 

diagnostics and identifying new therapies 

based on a better understanding of the 

pathobiology is becoming possible with 

discoveries such as those described above. 

‘‘ Overall, 2011 was an 

astounding year in terms 

of publications focusing on 

nondialysis CKD 

Predicting progression of CKD and 

outcomes of patients with CKD has been 

the focus of many publications over the 

past 2 years. Increasingly, investigators 

have identified aspects of kidney disease 

that portend poorer outcomes. A series of 

papers have described the ability of simple 

laboratory parameters to predict progression 

to ESRD over 5 years, 4 ’’ 

and highlighted 

that the rate of eGFR decline needs 


■ Consensus is increasing in the clinical and 

scientific community that classification 

of chronic kidney disease (CKD) needs 

to evolve to a more complex staging 

system that includes etiology, albuminuria, 

estimates of glomerular filtration rate and 

other available parameters 1,4,7 

■ More sophisticated methods of 

genotyping and phenotyping individuals 

have led to an improved ability to predict 

outcomes in patients with CKD 2,3,8 

■ The SHARP trial determined that a 

lipid-lowering strategy safely reduced 

atherosclerotic events in patients with 

CKD; these findings, which showed that 

the benefits were proportional to the lipid 

lowering achieved, irrespective of initial 

lipid values, have huge implications for 

clinical care 10 

to be considered in prediction equations, 5 

as well as the need to incorporate urine 

albumin excretion and estimates of GFR 

into risk prediction models 6 in patients 

with established CKD. The report of the 

consensus conference arranged under the 

KDIGO (Kidney Disease Improving Global 

Outcomes) organizational banner helped to 

consolidate a series of key conceptual issues 

relating to prognosis and risk stratification. 7 

Another important paper was that by 

Isakova et al., who demonstrated the importance 

of fibroblast growth factor 23 (FGF23) 

in predicting adverse outcomes in patients 

with CKD. 8 Levels of FGF23 demonstrated 

a stepwise increase in association with 

mortal ity and ESRD. Within the context 

of our increasing knowledge of the unique 

role of FGF23 in cardiac hypertrophy and 

potential therapeutic interventions, this 

study has refocused the nephrology community 

on the utility of newer biomarkers 

in risk stratification and in understanding 

the underlying biological processes involved 

in disease progression. 

The importance of well-conducted clinical 

trials that answer questions of key importance 

cannot be overstated. Two such papers 

were published in 2011, one addressing a 

new compound that might delay dialysis in 

patients with CKD, and the other addressing 

atherosclerotic events in patients with CKD. 

A study examining the effect of bardoxolone 

(an oral antioxidant, anti-inflammatory 

modulator) in patients with diabetes and 

CKD, demonstrated an improvement in 

eGFR at 24 weeks and 52 weeks in the participants. 

9 This study is the first to potentially 

offer some hope to patients with CKD, 

although issues related to mechanism of 

NEPHROLOGY 

action of the medication, long-term effects 

of increasing eGFR (that is, potential for 

accelerated progression), and utility in all 

clinical circumstances were not addressed 

in this phase II study. However, these findings, 

which show that therapeutic agents 

that might improve kidney function exist, 

are a source of optimism for the millions 

of patients with CKD. 

The SHARP study, an international 5-year 

randomized, placebo-controlled trial of 

>9,000 patients with CKD, found that active 

lipid-lowering treatment (simva statin 20 mg 

and ezetimibe 10 mg) was effective in reducing 

atherosclerotic events in patients both 

on and off dialysis. 10 This study is seminal 

in that it is the largest trial ever conducted 

in CKD, and enables clini cians to appreciate 

the benefit and very low risk profile of 

a fixed dose of lipid-lowering medication 

for this population. Although the study 

was not powered to examine mortality, the 

results did demon strate a 17% reduction in 

major atherosclerotic events. Publication of 

this study in the Lancet further validates the 

importance of these findings and the impact 

it is likely to have on general care. Moreover, 

the consistent finding that for any lowering 

of LDL-cholesterol levels, there was a benefit 

to patients with CKD similar to that found 

in the general population, adds credence to 

the hypothesis that atherosclerotic events 

can be ameliorated by targeted therapy in 

a wide range of patients. The SHARP study 

also reminds us that morbidity and mortality 

in CKD is more complex than simply 

being linked to atherosclerotic events, and 

thus highlights that there is more research 

to be done. 

Overall, 2011 was an astounding year 

in terms of publications focusing on nondialysis 

CKD. The majority of these papers 

are in general medical journals, 1,3,4,8–10 which 

is further testimony to the recognition of 

the importance of this area of medicine. 

The overall message from these studies 

is that CKD is important, identi fiable by 

simple means, is variable in its expression 

and outcomes, and both progressive disease 

and associated comorbidi ties are amenable 

to thera peutic interventions, which is reassuring 

for patients and their caregivers. 

Ongoing genomic and proteomic studies will 

further unravel the mystery of CKD progression 

and outcomes. The breadth and depth 

of nephrology insights and understandings 

continues to grow, as is evidenced in this 

landmark year. With such growth, we would 

anticipate an exciting future for both science 

and clinical care in the years to come. 


NEPHROLOGY 

Division of Nephrology, Department of 

Medicine, St Paul’s Hospital, University of 

British Columbia, 1081 Burrard Street, Room 

6010‑A, Vancouver, BC V6Z 1Y6, Canada. 

alevin@providencehealth.bc.ca 


A. Levin declares an association with the following 

company: Merck. See the article online for full 

details of the relationship. 

1. Peralta, C. A. et al. Detection of chronic kidney 

disease with creatinine, cystatin C, and urine 

albumin-to-creatinine ratio and association 

with progression to end-stage renal disease 

and mortality. JAMA 305, 1545–1552 (2011). 

2. Friedman, D. J., Kozlitina, J., Genovese, G., 

Jog, P. & Pollak, M.R. Population-based risk 

assessment of APOL1 on renal disease. J. Am. 

Soc. Nephrol. 22, 2098–2105 (2011). 

3. Wei, C. et al. Circulating urokinase receptor as 

a cause of focal segmental 

glomerulosclerosis. Nat. Med. 17, 952–960 

(2011). 

4. Tangri, N. et al. A predictive model for 

progression of chronic kidney disease to 

kidney failure. JAMA 305, 1553–1557 (2011). 

5. Perkins, R. M. et al. GFR decline and mortality 

risk among patients with chronic kidney 

disease. Clin. J. Am. Soc. Nephrol. 6, 

1879–1886 (2011). 

6. Astor, B. C. et al. and the Chronic Kidney 

Disease Prognosis Consortium. Lower 

estimated glomerular filtration rate and higher 

albuminuria are associated with mortality and 

end-stage renal disease. A collaborative metaanalysis 

of kidney disease population cohorts. 

Kidney Int. 79, 1331–1340 (2011). 

7. Levey, A. S. et al. The definition, classification, 

and prognosis of chronic kidney disease: 

a KDIGO Controversies Conference report. 

Kidney Int. 80, 17–28 (2011). 

8. Isakova, T. et al. for the Chronic Renal 

Insufficiency Cohort (CRIC) Study Group. 

Fibroblast growth factor 23 and risks of 

mortality and end-stage renal disease in 

patients with chronic kidney disease. JAMA 

305, 2432–2439 (2011). 

9. Pergola, P. E. et al. for the BEAM Study 

Investigators. Bardoxolone methyl and kidney 

function in CKD with type 2 diabetes. N. Engl. J. 

Med. 365, 327–336 (2011). 

10. Baigent, C. et al. on behalf of the SHARP 

Investigators. The effects of lowering LDL 

cholesterol with simvastatin plus ezetimibe in 

patients with chronic kidney disease (Study of 

Heart and Renal Protection): a randomised 

placebo-controlled trial. Lancet 377, 

2181–2192 (2011). 

DIALYSIS IN 2011 

Can cardiovascular risk in dialysis 

patients be decreased? 

Peter Stenvinkel and Peter Bárány 

More than 1.4 million patients are on renal replacement therapy 

worldwide. Mortality in patients with end-stage renal disease (ESRD) is 

as high as that seen in some types of metastatic cancer, and premature 

cardiovascular disease is the major killer in ESRD. Several publications in 

2011 addressed how interventions can modify cardiovascular risk factors 

and improve outcomes. 

Stenvinkel, P. & Bárány, P. Nat. Rev. Nephrol. 8, 72–74 (2012); published online 13 December 2011; 

doi:10.1038/nrneph.2011.212 

Although nephrologists have witnessed 

many technical advances in dialysis therapy 

over the past few decades, these improvements 

have translated into only minor 

reductions in mortality rate. Another major 

concern in nephrology is that several randomized 

controlled trials (RCTs) have 

not been able to demonstrate a significant 

effect of targeting various traditional and 

nontraditional risk factors on outcomes in 

this high-risk patient group. Inflammation 

seems to be a major driving force for the 

uremic phenotype and the majority of 

dialy sis patients have signs of persistent lowgrade 

inflammation with repetitive bursts 

of increased inflammatory activity. Because 

increased levels of circulating inflammatory 

biomarkers, such as C-reactive protein 

(CRP), pentraxin 3, and IL-6, consistently 

predict poor outcome in dialysis patients, 

inflammation seems to be a logical therapeutic 

target for putative anti-inflammatory 

nutritional and pharmaco logical interventions 

in this high-risk patient group. Recent 

observational studies suggest that the 

presence of persistent inflammation via a 

catalytic effect magnifies the risk of poor 

outcome via mechanisms related to selfenhancement 

of the inflammatory cascade 

and exacerbation of wasting and vascular 

calcification processes. 1 Results from a 

2011 study in a cohort of 225 hemodialysis 

patients followed over a period of 13 years 

support the catalyst hypothesis: inflammation 

was shown to amplify the risk of 

death and cardio vascular events associated 

with high asymmetric dimethylarginine 

(ADMA) levels. 2 Given the multi factorial 

origin of uremic inflammation, treatment 

is complex and the nephrologist needs to 

consider both factors related to the dialysis 

procedure (such as dialysis catheters and 

quality of dialysate) and factors unrelated 

to the dialysis procedure per se (such as 

infectious complica tions and volume overload). 

Nevertheless, following the exclusion 

of such factors, no apparent reason for 

persistent low-grade inflammation would 

be found in a consider able proportion of 

patients on dialysis. In a small RCT of 22 

patients published in 2011, Hung et al. 3 

demonstrated that 4 weeks of treatment 

with a recombinant human IL-1 receptor 

antagonist (anakinra) significantly reduced 

mean CRP level (by 53%) and mean IL-6 

level (by 40%), while mean prealbumin 

level increased by 23%. Moreover, the anti- 

cytokine treatment was well tolerated and 

safe. Although the small patient number and 

the short treatment period limit the value of 

this study, it still provides important information 

to the nephrology community. It is 

the first study showing that targeted anticytokine 

treatment decreases inflammation 

parameters in this patient group. Thus, 

long-term studies should be initiated to 

study the impact of anti- inflammatory treatment 

strategies on cardiovascular outcomes, 

quality of life, nutritional status and death in 

patients on dialysis. 

‘‘ Inflammation seems to be a 

major driving force for the uremic 

phenotype... 

The Study of Heart and Renal Protection 

(SHARP), also published in 2011, is the 

largest randomized study ever conducted 

in nephrology and included 9,270 patients 

random ized to receive either 20 mg simvastatin 

plus 10 mg ezetimibe daily or 

placebo. 4 ’’ 

One-third of the participants 

were dialysis dependent (2,527 on hemodialysis 

and 496 on peritoneal dialysis) 

and median follow-up was 4.9 years. In the 

whole cohort, treatment with simvastatin 

plus ezetimibe resulted in a 17% reduction 

in the primary end point of the risk of 

major athero sclerotic events (relative risk 

0.83; 95% CI 0.74–0.94). Significant reductions 

in revascularization procedures and 

non hemorrhagic strokes contributed most 

to the effect on the primary end point. 

Importantly, treatment with simvastatin 

plus ezetimibe was not associ ated with 


any survival benefit or a renal protective 

effect. Although the effect on the primary 

end point was similar in all subgroups, 

the risk reduction was less prominent in 

patients on dialysis (relative risk 0.90; 95% 

CI 0.75–1.08) than in nondialysis patients 

(relative risk 0.78; 95% CI 0.67–0.91). Thus, 

the modest effect on cardiovascular risk in 

patients on dialysis is of a similar magnitude 

to that reported in previous studies of statins 

(nonsignificant risk reductions of 8% in the 

4D study and 4% in AURORA). Persistent 

inflammation and comorbidities may influence 

the effects of lipid- lowering treatment 

in patients on dialysis. Although the precise 

role of these factors and the mechanism/s 

through which they interact with statin 

treatment are not yet evident, it can be speculated 

that if persistent inflammation serves 

as a catalyst and magnifies risk, 1 the effect 

of long-term statin treatment may differ 

in patients on dialysis with and without 

inflammation; these groups should be analyzed 

separately. Comorbidities, such as diabetes, 

may also influence the cardiovascular 

effects of statin treatment in this patient 

group. To determine whether rosuvastatin 

might reduce the risk of cardiac events in 

731 hemo dialysis patients with diabetes, a 

post hoc analysis of the AURORA cohort 

was performed. 5 Rosuvastatin treatment 

significantly reduced the rates of cardiac 

events by 32% among patients with diabetes. 

However, it is a concern that although 

there was no difference in overall stroke 

incidence between the rosuvastatin and 

the placebo groups, rosuvastatin-treated 

patients with diabetes had a higher risk of 

hemorrhagic strokes than the placebo group 

(relative risk 5.21; 95% CI 1.17–23.27). 

The high prevalence of atrial fibrillation 

is another major clinical problem in dialysis 

units. In a recent study based on 2.5 million 

observations of hemodialysis patients, 

Winkelmayer et al. 6 showed that the prevalence 

of atrial fibrillation had increased 

threefold from 1992 (3.5%) to 2006 (10.7%). 

They also showed that mortality was twice 

as high among hemodialysis patients with 

atrial fibrillation compared to those without 

atrial fibrillation. In 2011, the same group 

also reported data from 2,313 hemodialysis 

patients with new-onset atrial fibrillation. 

Whereas patients treated with warfarin had 

double the risk of hemorrhagic stroke compared 

with nonusers, the risk of ischemic 

stroke did not differ between users and nonusers 

of warfarin. 7 As warfarin treatment 

does not reduce the risk of ischemic stroke 

and, in addition to increasing the risk of 


■ Inflammation interacts with other 

cardiovascular risk factors in the 

uremic milieu, such as asymmetric 

dimethylarginine, and increases the risk 

of poor outcomes 2 

■ Short-term treatment with a recombinant 

human IL-1 receptor antagonist reduces 

inflammatory biomarkers in patients on 

hemodialysis 3 

■ Lipid-lowering treatment is associated 

with beneficial effects on major 

atherosclerotic events in the entire 

chronic kidney disease population; 

the effect is less pronounced in the 

subpopulation of dialysis patients 4 

■ The prevalence of atrial fibrillation in 

North American hemodialysis patients 

increased threefold between 1992 and 

2006 6 

■ Whereas warfarin treatment does not 

reduce the risk of ischemic stroke, it 

increases the risk of hemorrhagic stroke 

in older hemodialysis patients with atrial 

fibrillation 7 

hemorrhagic stroke, may have a role in both 

the progression of vascular calcification and 

in the life-threatening condition calciphylaxis, 

the risks of war farin treatment seem 

to outweigh its potential bene ficial effects 

in dialy sis patients with atrial fibrilla tion. 

Thus, until an adequately powered RCT 

settles the important question as to whether 

warfarin reduces the overall risk of stroke 

and improves survival it seems advisable not 

to prescribe vitamin K antagonists, such as 

warfarin, to patients on dialysis with atrial 

fibrillation. This finding should also prompt 

the initiation of studies to evaluate the safety 

and efficacy of novel anti coagulant treatment 

strategies in patients with advanced 

chronic kidney disease, such as drugs targeting 

factor IIa (dabigatran) and factor Xa 

(rivaroxaban, apixaban and edoxaban) 

in the coagulation cascade. Indeed, in a 

recent RCT conducted in 18,201 patients 

with atrial fibrillation (but without kidney 

disease), apixaban was superior to warfarin 

in preventing stroke or systemic embolism, 

caused less bleeding, and resulted in 

lower mortality. 8 

The effects of the intensity of dialysis on 

morbidity and mortality was first studied 

in the 1981 National Cooperative Dialysis 

study, which suggested that a longer hemodialysis 

duration aiming at a predialysis 

blood urea nitrogen level of 20 mmol/l 

resulted in less morbidity than a shorter 

hemodialysis duration. The results of the 

2002 HEMO study 9 showed that aiming 

NEPHROLOGY 

at a higher dialysis dose did not result in 

signifi cant benefits on mortality or morbidity 

(over standard doses) in patients 

undergoing thrice-weekly hemo dialysis. In 

2010, the randomized study by the Frequent 

Hemodialysis Network (FHN) studied the 

effect of frequent hemo dialysis versus conventional 

hemodialysis (six times weekly 

versus three times weekly) in 245 patients 

followed up for 1 year. 10 Frequent hemodialysis 

was associated with significant 

beneficial effects on the risk of an increase 

in left ventricular muscle mass and the 

risk of worse physical health scores as well 

as improved control of hypertension and 

hyperphosphatemia. The drawback was 

a 71% increase in the risk of requiring 

interventions related to vascular access. 

Although frequent hemodialysis is a promising 

modality, the cost–benefit ratio over 

longer follow-up periods than in the FHN 

study remains to be evaluated. 

In conclusion, several studies published 

in 2011 have provided the nephrology 

community with new small pieces of 

knowledge to add to the complex puzzle 

of the increased risk of premature cardiovascular 

death in patients on dialysis. 

Based on current knowledge, we conclude 

that inflammatory biomarkers and an 

assessment of atrial fibrillation should be 

included in the risk factor profile monitored 

by nephrologists. Whereas statin 

therapy seems to have a modest, but significant, 

beneficial effect on cardiac events, 

vitamin K antagonist treatment cannot be 

advocated in dialysis patients with atrial 

fibrillation until an RCT has proved its 

safety and efficacy. 

Division of Renal Medicine, Department of 

Clinical Science, Intervention and Technology, 

Karolinska University Hospital at Huddinge, 

Karolinska Institutet, SE 141 86 Stockholm, 

Sweden (P. Stenvinkel, P. Bárány). 

Correspondence to: P. Stenvinkel 

peter.stenvinkel@ki.se 


P. Stenvinkel declares an association with the 

following company: Gambro. See the article online 

for full details of the relationship. P. Bárány declares 

no competing interests. 

1. Carrero, J. J. & Stenvinkel, P. Of persistent 

inflammation as a catalyst for other risk factors 

in chronic kidney disease. a hypothesis 

proposal. Clin. J. Am. Soc. Nephrol. 4, S49–S55 

(2009). 

2. Tripepi, G. et al. Inflammation and asymmetric 

dimethylarginine for predicting death and 

cardiovascular events in ESRD patients. Clin. J. 

Am. Soc. Nephrol. 7, 1714–1721 (2011). 

3. Hung, A. M., Ellis, C. D., Shintani, A., Booker, C. 

& Ikizler, T. A. IL-1β receptor antagonist reduces 


NEPHROLOGY 

inflammation in hemodialysis patients. J. Am. 

Soc. Nephrol. 22, 437–442 (2011). 

4. Baigent, C. et al. The effects of lowering LDL 

cholesterol with simvastatin plus ezetimibe in 

patients with chronic kidney disease (Study of 

Heart and Renal Protection): a randomised 

placebo-controlled trial. Lancet 377, 

2181–2192 (2011). 

5. Holdaas, H. et al. Rosuvastatin in diabetic 

hemodialysis patients. J. Am. Soc. Nephrol. 22, 

1335–1341 (2011). 

6. Winkelmayer, W. C., Patrick, A. R., Liu, J., 

Brookhart, M. A. & Setoguchi, S. The increasing 

prevalence of atrial fibrillation among 

hemodialysis patients. J. Am. Soc. Nephrol. 22, 

349–357 (2011). 

7. Winkelmayer, W. C., Liu, J., Setoguchi, S. & 

Choudhry, N. K. Effectiveness and safety of 

warfarin initiation in older hemodialysis 

patients with incident atrial fibrillation. Clin. J. 

Am. Soc. Nephrol. http://dx.doi.org/10.2215/ 

CJN.04550511. 

8. Granger, C. B. et al. Apixaban versus warfarin in 

patients with atrial fibrillation. N. Engl. J. Med. 

365, 981–992 (2011). 

9. Eknoyan, G. et al. Effect of dialysis dose and 

membrane flux in maintenance hemodialysis. 

N. Engl. J. Med. 347, 2010–2019 (2002). 

10. Chertow, G. M. et al. In-center hemodialysis 

six times per week versus three times per 

week. N. Engl. J. Med. 363, 2287–2300 

(2010). 

TRANSPLANTATION IN 2011 

New agents, new ideas and new 

hope 

Titte R. Srinivas and Bruce Kaplan 

The past year was marked by several excellent studies that represent 

important therapeutic advances in kidney transplantation or that further 

our understanding of the genetic basis of chronic allograft dysfunction, 

clinical tolerance and outcomes of kidney transplantation. 

Srinivas, T. R. & Kaplan, B. Nat. Rev. Nephrol. 8, 74–75 (2012); published online 20 December 2011; 

doi:10.1038/nrneph.2011.215 

The year 2011 was marked by the addition 

of an important alternative to calcineurin 

inhibitors for immuno suppression 

in kidney transplantation. Calcineurin 

inhibitor-based combina tions are the most 

frequently utilized immuno suppressive 

regimens in kidney transplantation, but 

they carry a metabolic burden and may 

be associated with both short-term and 

possibly progressive diminution in graft 

function. Belatacept is a costimulation 

blocker that binds to CD80 and CD86 

on antigen- presenting cells and provides 


■ 3-year follow-up of BENEFIT demonstrates 

that belatacept provides superior renal 

function outcomes to ciclosporin 3 

■ Sensitized patients treated with a 

desensitization regimen have better 

survival than patients on dialysis 

or sensitized patients who undergo 

compatible transplantation 4 

■ Discovery of APOL1 variants in African 

Americans points to a biological 

influence rather than race underlying 

transplantation outcomes 6 

■ Increased cold ischemia times of 

extended criteria donor kidneys are 

associated with delayed graft function, 

but do not affect graft survival 10 

effective immuno suppression while being 

devoid of renal and nonrenal metabolic 

adverse effects. 1 A phase III study of 

belatacept (BENEFIT) published in 2010 

reported superior renal function and an 

improved cardiovascular and metabolic 

risk profile compared with a ciclosporinbased 

regimen. 2 In this trial, 686 de novo 

kidney transplant recipients (of living and 

standard criteria deceased donor kidneys) 

were randomly assigned to more-intensive 

or less-intensive belatacept regimens or to 

ciclosporin. All patients received basiliximab 

induction therapy, mycophenolate 

mofetil and corticosteroids. Equivalent 

rates of graft and patient survival were 

noted despite an increased frequency and 

severity of early rejection episodes and 

increased frequency of post-transplant 

lympho proliferative disorder associated 

with belatacept. 2 

Vincenti et al. have now reported on the 

efficacy and safety of belatacept at 3 years 

post-transplantation in the BENEFIT 

study. 3 Graft survival was equivalent across 

all regimens. At year 3 post- transplantation, 

the mean estimated glomerular filtration 

rate (eGFR) was 21 ml/min/1.73 m 2 higher 

in the belatacept groups than in the ciclosporin 

group. More importantly, from 

month 3 through to month 36, the slope 

of eGFR in the belatacept groups averaged 

1.1 ml/min/1.73 m 2 per year versus 

–2.0 ml/min/1.73 m 2 per year with ciclosporin. 

Neither a significant increase in 

acute rejection episodes nor new cases of 

post-transplant lymphoproliferative disorder 

after 18 months post-transplantation 

were observed. 3 Taken together, these findings 

are indeed gratifying and represent 

the emergence of a non-nephrotoxic and 

efficacious immunosuppressive regimen 

in renal transplantation. This study also 

demon strated a disconnect between rejection 

rates and graft survival and function, 

which either reflects short follow-up or 

reasons that prompt reconsideration of 

the relationship between classic T-cellmediated 

rejection and outcomes. Although 

initial results from BENEFIT are promising, 

their generalizability to clinical practice at 

large will depend on a paradigm shift from 

oral maintenance therapy to infusion-based 

therapy. As such, whether the promising 

initial results are sustainable on logistical 

and economic grounds needs further study. 

Sensitized transplant candidates have 

prolonged waiting times, a reduced 

transplanta tion rate and an increased rate 

of death compared with nonsensitized 

candidates. Although numerous centers 

report successful utilization of desensitization 

regimens in renal transplantation, 

they are plagued by the absence of suitable 

control groups. Montgomery et al. compared 

outcomes in 211 HLA-sensitized live 

donor kidney transplant recipients treated 

with low-dose intra venous immunoglobulin 

and plasma pheresis with that of 

two matched control groups drawn from 

the United Network for Organ Sharing 

kidney transplant waiting list who either 

remained on dialysis (dialysis- only group) 

or who were dialyzed or underwent 

HLA-compatible renal transplantation 

(dialysis-or- transplantation group). 4 In 

the desensitized group, estimates of patient 

survival were 90.6%, 85.7% and 80.6% at 1, 

3 and 5 years, respectively, versus 91.1%, 

67.2% and 51.5% in the dialysis-only 

group and 93.1%, 77.0% and 65.6% in the 

dialysis-or-transplantation group (overall 

P

have not been compared systematically to 

the cost of remaining on dialysis. In addition, 

this study compared patient survival 

with living donor transplantation following 

desensitiza tion with those accrued on 

the waitlist. Whether these encouraging 

observa tions could extend to deceased 

donor transplantation after successful 

desensitization remains to be seen. 

African Americans are at increased risk 

of end-stage renal disease compared with 

white individuals. Recent studies suggest an 

association between variants of the apolipoprotein 

L1 gene (APOL1) and nondiabetic 

nephropathy among African Americans. 5 

In a single-center study, kidneys from 

African American deceased donors with 

two APOL1 risk variants were more likely to 

fail (HR 3.48, P = 0.008) than kidneys from 

individuals with one or no APOL1 risk variants. 

6 These associations outweighed the 

risk of graft loss associated with African 

American ancestry. This study highlights 

that transplant outcomes are more likely to 

be based on biology than on arbitrary and 

often culturally based definitions of race. 

Whether or not donor genotype or donor– 

recipient genotype interactions influence 

transplant outcomes through nonimmunological 

mechanisms demands confirmation. 

More importantly, the application of these 

associations to improve matching of donors 

and recipients in organ allocation schemes 

merits further study. 

Successful transplantation in the clinical 

arena is inseparable from the pharmacopeia 

that facilitates successful transplantation. 

Immunosuppressive drugs are associated 

with well-known immunological and nonimmunological 

adverse effects. However, it 

is increasingly apparent that a small number 

of recipients of renal and liver allografts 

continue to have excellent graft function 

many years (sometimes decades) after 

stopping immunosuppression. Such individuals 

are described as being operationally 

tolerant. A unique B-cell expression signature 

associated with increased numbers of 

naive and transitional B cells in peripheral 

blood has been described in operationally 

tolerant kidney transplant recipients. 7 

A recent study comparing character istics 

of liver and kidney transplant recipients 

who are operationally tolerant showed 

that the gene-expression signatures of 

peripheral blood mononuclear cells in 

these individuals was very different, with 

no significant detectable overlap between 

their immuno phenotypic profiles. 8 By contrast, 

tolerant and non tolerant liver recipients 

had similar peripheral blood B-cell 

phenotypic markers. 8 

‘‘ ...transplant outcomes are 

more likely to be based on biology 

than on arbitrary ... definitions of 

race 

It is important to note that the studies 

discussed above represent associations and 

do not imply causal relationships. Patients 

who maintain excellent graft survival 

despite discontinuing immuno suppression 

might differ considerably from those who 

reject under similar circumstances; findings 

drawn from operationally tolerant 

individuals could therefore be affected 

by survivorship bias. Whether genomic 

and immunophenotypic markers associated 

with prolonged discontinuation of 

immuno suppression and excellent graft 

survival could be identified prospectively 

and enable programmed discontinuation 

of immunosuppression in selected recipients 

earlier in the course of transplantation 

deserves further systematic study. 

Extended criteria donor (ECD) kidneys 

permit successful transplantation especially 

among transplant candidates with 

poor expected waitlist survival, such as the 

elderly and those with diabetes. 9 However, 

delays in the placement of ECD kidneys are 

associated with increased cold ischemia 

times (CITs) and a high rate of discard of 

such organs. A recent study using data from 

the Scientific Registry of Renal Transplant 

Recipients examined the effect of increasing 

CITs on graft survival among recipients 

of paired kidneys (kidneys from the 

same deceased donor transplanted to 

two different recipients where one donor 

had delayed graft function and the other 

did not). 10 ’’ 

Longer CITs were associated 

with increasing incidence of delayed graft 

function. However, graft survival did not 

signifi cantly differ across the range of CITs 

studied. Although this study is limited by 

NEPHROLOGY 

its retrospective nature and is prone to 

selection bias, it provides some impetus to 

reconsider discard of ECD kidneys with 

higher CITs and optimize ECD utilization 

and acceptance. 

The articles summarized above provide 

food for thought and prospects for further 

inquiry in coming years. We look forward 

to fruitful developments in these and related 

areas in clinical transplantation. 

Department of Nephrology and Hypertension, 

Glickman Urological and Kidney Institute, 9500 

Euclid Avenue, Cleveland, OH 44195, USA 

(T. R. Srinivas). Division of Nephrology, 

University of Arizona School of Medicine, 

1501 North Campbell Avenue, Tucson, 

AZ 85724, USA (B. Kaplan). 

Correspondence to: B. Kaplan 

bkaplan@deptofmed.arizona.edu 



1. Larsen, C. P. et al. Rational development of 

LEA29Y (belatacept), a high-affinity variant of 

CTLA4-Ig with potent immunosuppressive 

properties. Am. J. Transplant. 5, 443–453 

(2005). 

2. Vincenti, F. et al. A phase III study of belataceptbased 

immunosuppression regimens versus 

cyclosporine in renal transplant recipients 

(BENEFIT study). Am. J. Transplant. 10, 

535–546 (2010). 

3. Vincenti, F. et al. Three-year outcomes from 

BENEFIT, a randomized, active-controlled, 

parallel-group study in adult kidney transplant 

recipients. Am. J. Transplant. http://dx.doi.org/ 

10.1111/j.1600–6143.2011.03785.x. 

4. Montgomery, R. A. et al. Desensitization in HLAincompatible 

kidney recipients and survival. 

N. Engl. J. Med. 365, 318–326 (2011). 

5. Friedman, D. J., Kozlitina, J., Genovese, G., 

Jog, P. & Pollak, M. R. Population-based risk 

assessment of APOL1 on renal disease. J. Am. 

Soc. Nephrol. 22, 2098–2105 (2011). 

6. Reeves-Daniel, A. M. et al. The APOL1 gene and 

allograft survival after kidney transplantation. 

Am. J. Transplant. 11, 1025–1030 (2011). 

7. Newell, K. A. et al. for the Immune Tolerance 

Network ST507 Study Group. Identification of a 

B cell signature associated with renal 

transplant tolerance in humans. J. Clin. Invest. 

120, 1836–1847 (2010). 

8. Lozano, J. J. et al. Comparison of 

transcriptional and blood cell-phenotypic 

markers between operationally tolerant liver 

and kidney recipients. Am. J. Transplant. 11, 

1916–1926 (2011). 

9. Merion, R. M. et al. Deceased-donor 

characteristics and the survival benefit of 

kidney transplantation. JAMA 294, 2726–2733 

(2005). 

10. Kayler, L. K., Srinivas, T. R. & Schold, J. D. 

Influence of CIT-induced DGF on kidney 

transplant outcomes. Am. J. Transplant. 11, 

2657–2664 (2011). 


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STROKE IN 2011 

Major advances across the spectrum 

of stroke care 

Lee H. Schwamm 

NEUROLOGY 

Several pivotal clinical trials that could have a major impact on the care of patients with stroke were published 

in 2011. The studies cover a wide range of stroke-care aspects, including stroke prevention, imaging to select 

patients for thrombolysis, therapies for stroke recovery, and stroke registries to improve care quality. 

Schwamm, L. H. Nat. Rev. Neurol. 8, 63–64 (2012); published online 10 January 2012; doi:10.1038/nrneurol.2011.225 

The current framework for analyzing the 

complete spectrum of stroke care is conceptualized 

in the ‘stroke systems of care’ model 1 

(Figure 1), as delineated in a policy statement 

of the American Stroke Association in 

2005. The model specifies seven domains of 

care—primary prevention; community education; 

notification and response of emergency 

medical services; acute stroke treatment; subacute 

stroke treatment and secon dary prevention; 

rehabili tation; and con tinuous quality 

improvement activities—and emphasizes the 

links between them. In 2011, five domains of 

the stroke systems of care model have witnessed 

major breakthroughs that have the 

potential to dramati cally influence the delivery 

of stroke care now and in the future, thereby 

further eroding the therapeutic nihilism that 

still surrounds much of stroke treatment. 

Nonvalvular atrial fibrillation is a major 

preventable cause of first ever and recurrent 

stroke. Warfarin has been the mainstay of 

therapy for almost half a century, but it has 

a narrow therapeutic range that is difficult to 

maintain in many patients, requires frequent 

monitoring, and is highly susceptible to drug 

and food interactions. The ARISTOTLE trial 2 

compared the oral direct factor Xa inhibitor 

apixaban with warfarin for efficacy in stroke 

prevention in over 1,800 patients with atrial 

fibrillation and an elevated stroke risk score. 

In both groups, just under 15% of patients 

had a prior myocardial infarction, and 20% 

had a prior stroke, transient ischemic attack 

or systemic embolism. The results showed 

that apixaban is superior to warfarin in 

reducing the risk of stroke or systemic embolism 

(incidence rates 1.27% versus 1.60% per 

year; HR 0.79; P

NEUROLOGY 


■ Apixaban is superior to warfarin in 

reducing the risk of stroke or systemic 

embolism, and is safer in reducing the 

risk of major bleeding or death 2 

■ Intracranial stenting produces higher rates 

of stroke and death than an intensive 

medical management strategy for severe 

symptomatic atherosclerotic stenosis 6 

■ A standardized computer algorithm for 

post‑processing of MRI scans may be 

superior to individual visual estimation for 

selecting patients for thrombolytic therapy 8 

■ A combination of fluoxetine and 

physical therapy could produce greater 

improvements in limb motor function 

after stroke than physical therapy alone 9 

■ Hospitals are rapidly adopting stroke 

quality improvement registries, which 

could reduce mortality, cost and 

complications of stroke by increasing the 

use of evidence‑based therapies 10 

When prevention fails, acute stroke 

manage ment begins. Early reperfusion of 

ische mic tissue is the primary goal, which is 

reflec ted in the mechanism of action of the 

only FDA-approved therapy for improving 

stroke outcomes: tissue plasminogen activator. 

The proportion of patients who are 

eligible for thrombolysis, however, remains 

disappointingly low, owing largely to the 

narrow time window for this treatment 

and exclusion of patients with mild stroke. 

Considerable efforts have been made to 

develop imaging biomarkers of the acute 

ischemic ‘penumbra’—brain tissue surrounding 

the lesion core that is vulnerable 

but salvageable with early reperfusion—in 

an attempt to expand the number of patients 

who can receive reperfusion therapy. 

Supporters of MRI-based patient selection 

for thrombolysis were dealt a blow 

3 years ago when the DIAS-2 trial 7 failed 

to meet its primary end point, as it used a 

widely accepted definition of the penum bra 

based on a mismatch between the volumes of 

ische mic brain tissue measured on diffusion 

versus perfusion MRI. The MRI-mismatch 

approach to patient selection could be 

improved by the use of a standard ized computer 

algorithm for post-processing of MRI 

scans, as suggested by a recent pooled analysis 

8 of the EPITHET and DEFUSE trials. 

The study emphasizes the importance of 

human error and inter-operator variability 

when visual inspection, rather than automated 

techniques, is used to determine suitability 

for reperfusion treatment. Ongoing 

trials are evaluating alternative strategies of 

MRI-based patient selection for intravenous 

reperfusion (MR WITNESS and EXTEND) 

or intra-arterial reperfusion (MR RESCUE). 

Patients with acute ischemic stroke are 

almost always left with a degree of dis ability 

that requires rehabilitative treatment. Early 

studies suggested that constraint therapy 

(immobilization of the ‘good’ arm to encourage 

use of the affected arm) and pharmacological 

stimulants could modulate brain 

plasticity after stroke and reduce the residual 

neurological deficit and subsequent disability. 

However, large-scale, well-designed 

randomized controlled trials to support these 

initial findings have not been performed. 

Important evidence for a beneficial 

effect of the antidepressant fluoxetine in 

stroke recovery was provided in 2011 by 

the FLAME trial. 9 In this phase II study, all 

patients received physiotherapy, and those 

who were randomly assigned to the fluoxetine 

group showed significantly greater 

improvement in motor function of the 

affected arm and leg at 90 days poststroke 

than did those assigned to the placebo 

group. Interestingly, differences between 

the study groups were still signifi cant after 

adjustment for depression or thrombolytic 

use, sug gesting that fluoxetine could 

be beneficial across many subgroups. The 

findings, which need to be confirmed in 

larger trials, hold promise for thousands of 

stroke survivors who may benefit from this 

and other re covery strategies to facilitate 

brain plasticity. 

With mounting pressure on funding and 

resources in the current economic downturn, 

efficient health-care delivery is becoming 

increasingly important. The Ameri can 

Heart Association’s ‘Get with The Guidelines®-Stroke’ 

(GWTG-Stroke) quality 

improve ment registry tracks characteristics, 

performance measures, and in-hospital outcomes 

in nearly 2 million patients admitted 

to almost 2,000 US hospitals with stroke or 

transient ischemic attack, and provides valuable 

information on the effectiveness and 

safety of care delivery. 10 This registry has 

played a vital part in the defini tion, assessment 

and validation of hospital performance 

metrics that have become the standard for 

measuring stroke-care quality. The latest 

GWTG-Stroke study 10 suggests that although 

in-hospital mortality may be lower at registry 

sites, the results are largely generalizable to 

patients in non-registry hospitals. The measures 

defined by GWTG-Stroke are among 

the first to be incorporated into a new, electronically 

derived set of quality measures in 

the Meaningful Use program, which aims to 

shift health records to an electronic system 

and define quality metrics in a more affordable, 

actionable and cost-effective manner. 

Strategies that seek to minimize the costly 

practice of capturing patient-level clinical 

information while maximizing the use of 

more cost-effective, administratively derived 

health records are likely to form the backbone 

of future quality improvement efforts. 

Together, the advances described above 

reflect progress across the spectrum of stroke 

care (Figure 1). From novel drug or device 

development to new uses for approved drugs, 

every step forward takes us closer to the ultimate 

goal of better outcomes at lower cost for 

patients with stroke and their families. 

Department of Neurology-ACC 720, Harvard 

Medical School, Massachusetts General 

Hospital, 55 Fruit Street, Boston, MA 02114, 

USA. 

lschwamm@partners.org 



1. Schwamm, L. H. et al. Recommendations for 

the establishment of stroke systems of care: 

recommendations from the American Stroke 

Association’s Task Force on the Development 

of Stroke Systems. Circulation 111, 

1078–1091 (2005). 

2. Granger, C. B. et al. Apixaban versus warfarin in 

patients with atrial fibrillation. N. Engl. J. Med. 

365, 981–992 (2011). 

3. Diener, H.‑C. et al. Dabigatran compared with 

warfarin in patients with atrial fibrillation and 

previous transient ischemic attack or stroke. 

Lancet Neurol. 9, 1157–1163 (2010). 

4. Patel, M. R. et al. Rivaroxaban versus warfarin 

in nonvalvular atrial fibrillation. N. Engl. J. Med. 

365, 883–891 (2011). 

5. Chimowitz, M. I. et al. Comparison of warfarin 

and aspirin for symptomatic intracranial arterial 

stenosis. N. Engl. J. Med. 352, 1305–1316 

(2005). 

6. Chimowitz, M. I. et al. Stenting versus 

aggressive medical therapy for intracranial 

arterial stenosis. N. Engl. J. Med. 365, 

993–1003 (2011). 

7. Hacke, W. et al. Intravenous desmoteplase in 

patients with acute ischaemic stroke selected 

by MRI perfusion–diffusion weighted imaging or 

perfusion CT (DIAS‑2): a prospective, 

randomised, double‑blind, placebo‑controlled 

study. Lancet Neurol. 8, 141–150 (2009). 

8. Lansberg, M. G. et al. RAPID automated patient 

selection for reperfusion therapy: a pooled 

analysis of the Echoplanar Imaging 

Thrombolytic Evaluation Trial (EPITHET) and the 

Diffusion and Perfusion Imaging Evaluation for 

Understanding Stroke Evolution (DEFUSE) 

study. Stroke 42, 1608–1614 (2011). 

9. Chollet, F. et al. Fluoxetine for motor recovery 

after acute ischaemic stroke (FLAME): 

a randomised placebo‑controlled trial. Lancet 

Neurol. 10, 123–130 (2011). 

10. Reeves, M. J. et al. Representativeness of the 

Get With The Guidelines‑Stroke Registry: 

comparison of patient and hospital 

characteristics among medicare beneficiaries 

hospitalized with ischemic stroke. Stroke 

http://dx.doi.org/10.1161/ 

STROKEAHA.111.626978. 


MOVEMENT DISORDERS IN 2011 

Translating new research findings 

into clinical practice 

Christine Klein and Dimitri Krainc 

The discovery of mutations that contribute to movement disorders 

has facilitated the identification of converging pathways and novel 

therapeutic targets. Successful translation of these research findings into 

clinical practice will require identification of early markers of disease 

progression, and recent research indicates that progress is being made in 

this area. 

Klein, C. & Krainc, D. Nat. Rev. Neurol. 8, 65–66 (2012); published online 20 December 2011; 

doi:10.1038/nrneurol.2011.212 

The prevalence of Parkinson disease (PD) 

and other neurodegenerative disorders 

is rapidly increasing worldwide and is 

expected to double by 2030, 1 yet not a single 

disease-modifying treatment exists for this 

disorder. Thus, translation of research findings 

into all aspects of clinical practice—that 

is, diagnosis, monitoring and treatment—in 

movement disorders is a high priority. One 

of the major challenges of translational 

research in movement disorders has been 

the apparent lack of specific molecular targets 

as platforms for drug development. 

How ever, as highlighted by a number of 

important studies published in 2011, the 

emergence of various forms of genetic PD 

has offered us an exciting opportunity to 

identify such targets. 

‘‘ Identification and monitoring 

of the earliest disease stages 

… is of great importance 

Most mutations that have been linked 

to PD and related synucleinopathies seem to 

converge on lysosomal and mito chondrial 

pathways, suggesting that disruptions of 

these pathways have key roles in disease 

pathogenesis. The importance of lysosomal 

function in synucleinopathies was highlighted 

in a recent study by Mazzulli and 

colleagues that examined Gaucher disease, 

a rare lysosomal storage disorder caused by 

mutations in the glucocerebro sidase (GBA1) 

gene. 2 ’’ 

Patients with Gaucher disease and 

their relatives have an increased incidence of 

PD, and patients with idiopathic PD have an 

elevated prevalence of mutations in GBA1. 

Interestingly, accumulated α-synuclein 

interferes with trafficking of glucocerebrosidase 

from the endo plasmic reticulum 

to the Golgi apparatus, which in turn leads to 

decreased glucocerebrosidase activity and 

more accumulation of α-synuclein. The 

bidirectional effects of α-synuclein and 

glucocerebro sidase form a positive feedback 

loop that, beyond a certain threshold, leads 

to self-propagating disease. 

The findings suggest that this molecular 

pathway applies also to patients with idiopathic 

PD or other synucleinopathies who 

carry a normal GBA1 gene. The results indicate 

that therapeutic targeting of mutated 

or normal gluco cerebrosidase to lysosomes 

would be expected to prevent or diminish 

the formation of toxic α-synuclein oligomers 

and break the vicious circle of α-synuclein 

aggregation and toxicity. Importantly, these 

findings were confirmed in human neurons 

derived from induced pluripotent stem 

cells, 2 which represent a major advance for 

the modeling of neurodegenerative and 

other diseases. 3 

The importance of lysosomal pathways 

in PD was further highlighted in two backto-back 

publications by Vilarino-Guell 

et al. 4 and Zimprich et al. 5 that described 

a dominantly inherited mutation in the 

vacuo lar protein sorting 35 (VPS35) gene as 

a novel, albeit rare, cause of late-onset PD. 

As a component of the retromer complex, 

VPS35 sorts cargo from endosomes back to 

the trans-Golgi network, and disruptions in 

this pathway are expected to affect lysosomal 

function. Intriguingly, both studies detected 

the same VPS35 mutation (Asp620Asn), in 

Swiss and Austrian kindreds, respectively, 

and the same mutation was also recently 

identified in a German pedigree. 6 When the 

analyses were extended to additional families 

from various ethnic backgrounds, both 

initial studies confirmed the Asp620Asn 

mutation in independent cases and found 

two additional variants in the VPS35 gene. 4,5 

On the basis of these studies, and previous 

data showing that the retromer regulates 

endosomal sorting of amyloid precursor 

NEUROLOGY 

protein in models of Alzheimer disease, it 

will be interesting to examine the role of 

VPS35 in the pathogenesis of PD. These 

studies also highlight the importance of 

next-generation sequencing for the discovery 

of genetic factors—many of which 

are likely to be rare—that cause or contribute 

to complex movement disorders. 7 

Besides improving our understanding of 

disease biology, the identification of monogenic 

forms of movement disorders has 

opened up a new window into the pre motor 

stage of neurodegenerative conditions—the 

historical frontrunner being Huntington 

disease—whereby individuals at risk can 

be studied prospectively. Identification 

and monitoring of the earliest disease 

stages, during which treatment and neuroprotection 

are expected to be most effective, 

is of great importance. Selection of carefully 

characterized and homogeneous cohorts of 

patients or at-risk individuals will be vital 

for the development of new drugs for PD 

and other movement disorders. This task 

would be greatly facilitated by employing 

adequate biomarkers for diagnosis of the 

disease, and for monitoring its course and 

potential effects of treatment. 

In a study published in PLoS ONE, 

Yanamandra et al. hypothesized that autoimmune 

reactivity towards specific proteins 

and self-assembled complexes that 

are involved in disease pathology may 

serve as sensitive biomarkers of neurodegeneration. 

8 The researchers measured 


■ α‑Synuclein and glucocerebrosidase 

form a bidirectional pathogenic loop, 

providing an important pathophysiological 

mechanism in the development of 

Parkinson disease (PD) 2 

■ Next‑generation sequencing has led to 

the discovery of a new gene (VPS35) 

associated with late‑onset PD; this 

finding implicates retrograde transport in 

PD pathogenesis 4,5 

■ α‑Synuclein‑reactive antibodies may 

serve as a new biomarker for PD, 

especially in its early phase 8 

■ Induced pluripotent stem cell‑derived 

neurons represent a patient‑specific 

cellular model with great potential for 

the study of disease biology 2 

■ The first double‑blind, sham‑surgery‑ 

controlled, randomized trial of viral gene 

transfer of glutamic acid decarboxylase 

resulted in improved motor scores in 

patients with PD, and the treatment 

was not associated with severe 

adverse events 9 


NEUROLOGY 

levels of auto antibodies against α-synuclein, 

the main component of Lewy bodies, in the 

serum of patients with PD in early and late 

stages of the disease. Significantly higher 

auto antibody levels were found in patients 

than in controls, but the antibody response 

decreased as the condition became more 

advanced. The authors interpreted this 

find ing in the context of a protective role for 

auto immunity in PD that seems to be stronger 

in the early phases of the disease, and 

may be of value as a biomarker, especially at 

this crucial stage of PD pathogenesis. 

‘‘ …the treatment of PD has 

been limited to symptomatic 

drug therapy and deep brain 

stimulation 

In the absence of neuroprotective therapies, 

the treatment of PD has been limited 

to symptomatic drug therapy and deep 

brain stimulation. To explore the potential 

of gene therapy, LeWitt and colleagues 

performed the first double-blind, shamsurgery- 

controlled, randomized trial of 

in vivo gene transfer in patients with PD. 9 

The investigators used adeno-associated 

viral vector (AAV2) for transduction of 

the gene encoding glutamic acid decarboxylase 

(GAD), an enzyme that catalyzes 

the decarb oxylation of glutamate to 

γ-aminobutyric acid and is expected to 

increase the inhibitory tone in the basal 

ganglia. The trial involved 55 patients aged 

30–75 years with levodopa-responsive 

PD, who were randomly assigned to sham 

surgery (n = 23) or AAV2–GAD infusions 

(n = 22) at baseline. 

At the 6-month study end point, 21 and 

16 patients were assessed in the shamtreated 

and gene-therapy groups, respectively. 

The mean Unified Parkinson’s 

Disease Rat ing Scale (UPDRS) motor score 

was found to have decreased by 8.1 points 

(23.1%) in the AAV2–GAD group and 

by 4.7 points (7.0%) in the sham group. 9 

’’ 

Over all, the study is encouraging, since the 

group dif ference was highly significant and 

no serious adverse events were observed in 

either group. Caveats of this study include 

rela tively small group sizes, a heterogeneous 

patient population in terms of age of onset, 

more-severe dis ease in the sham group, 

limited dis criminatory power of the UPDRS 

(maximum 108 points) in the lower range, 

and the relatively short follow-up period. 

In conclusion, these studies highlight the 

importance of identifying the molecular 

underpinnings of disease pathways to 

uncover therapeutic targets. The discovery 

of genetic mutations in these pathways has 

sug gested converging mechanisms in the 

patho genesis of movement disorders. In 

order to rapidly translate research advances 

into the clinic, it is critically important to 

iden tify markers of disease progression, 

especially in individuals who are at risk of 

developing a neurodegenerative disease. 

Department of Neurology, University of Lübeck, 

Ratzeburger Allee 160, 23538 Lübeck, 

Germany (C. Klein). Department of Neurology, 

Massachusetts General Hospital, Harvard 

Medical School, 114 16 th Street, Room 2007, 

Charlestown, MA 02129, USA (D. Krainc). 

Correspondence to: C. Klein 

christine.klein@neuro.uni-luebeck.de 


C. Klein is funded by a career development award 

from the Hermann and Lilly Schilling Foundation. 

D. Krainc is supported by the National Institute of 

Neurological Disorders and Stroke and the 

CHDI Foundation. 



1. Dorsey, E. R. et al. Projected number of people 

with Parkinson disease in the most populous 

nations, 2005 through 2030. Neurology 68, 

384–386 (2007). 

2. Mazzulli, J. R. et al. Gaucher disease 

glucocerebrosidase and α‑synuclein form a 

bidirectional pathogenic loop in 

synucleinopathies. Cell 146, 37–52 (2011). 

3. Kiskinis, E. & Eggan, K. Progress toward the 

clinical application of patient‑specific 

pluripotent stem cells. J. Clin. Invest. 120, 

51–59 (2011). 

4. Vilarino‑Guell, C. et al. VPS35 mutations in 

Parkinson disease. Am. J. Hum. Genet. 89, 

162–167 (2011). 

5. Zimprich, A. et al. A mutation in VPS35, 

encoding a subunit of the retromer complex, 

causes late‑onset Parkinson disease. Am. 

J. Hum. Genet. 89, 168–175 (2011). 

6. Kumar, K. W. et al. Frequency of the D620N 

mutation in VPS35 in Parkinson disease. Arch. 

Neurol. (in press). 

7. Lill, C. M. & Bertram, L. Complex genetics of 

neurodegenerative diseases. Semin. Neurol. 

(in press). 

8. Yanamandra, K. et al. α‑Synuclein reactive 

antibodies as diagnostic biomarkers in blood 

sera of Parkinson’s disease patients. PLoS ONE 

6, e18513 (2011). 

9. LeWitt, P. A. et al. AAV2–GAD gene therapy for 

advanced Parkinson’s disease: a double‑blind, 

sham‑surgery controlled, randomised trial. 

Lancet Neurol. 10, 309–319 (2011). 

MULTIPLE SCLEROSIS IN 2011 

Advances in therapy, imaging 

and risk factors in MS 

Bianca Weinstock–Guttman and Murali Ramanathan 

Multiple sclerosis research in 2011 produced a combination of new 

therapeutic developments and innovative findings. Teriflunomide showed 

beneficial effects in a phase III trial, quantification methods for MRI 

lesions that should improve monitoring of disease progression were 

devised, and a link between high cholesterol and low vitamin D emerged. 

Weinstock–Guttman, B. & Ramanathan, M. Nat. Rev. Neurol. 8, 66–68 (2012); published online 10 January 2012; 

doi:10.1038/nrneurol.2011.213 

For multiple sclerosis (MS), the research 

milestones of 2011 were a combination of 

new therapeutic developments and innovative 

findings that might help to explain the 

heterogeneity in both disease progression 

and responses to therapy in patients with 

MS. The new oral therapy teriflunomide 

showed beneficial effects in a large phase III 

clinical trial, 1 which provides hope for better 

and more-convenient control of MS in the 

future. The identification of new methods 

to quantify cortical lesions on MRI will 

improve our ability to monitor disease progression, 

2 and studies have identified raised 

cholesterol and reduced vitamin D levels as 

detrimental factors in patients with MS. 3,4 

From a therapeutic standpoint, 2011 

will be remembered as a defining year 

for MS. Following a successful clinical 

trial, reported in 2010, 5 fingolimod—an 

oral disease-modifying therapy for MS— 

received regulatory approval and became 

available to patients in over 50 countries 

including the USA, the European Union 

and, most recently, Japan. The results from 

a phase III clinical trial of teriflunomide 

(another oral therapy for MS) were published 

in October 2011 in The New England 

Journal of Medicine. 1 Teriflunomide is the 

active metabolite of leflunomide, which 

is already approved for the treatment of 

patients with rheumatoid arthritis, and it 


acts by reversi bly inhibiting dihydroorate 

dehydrogenase, a key mitochondrial 

enzyme involved in pyrimidine synthesis, 

to block the proliferation of rapidly dividing 

lymphocytes that are thought to drive 

inflammation in MS. 

The trial reported by O’Connor et al. 1 

involved 1,088 patients with active relapsing– 

remitting MS (RRMS)—defined as one or 

more relapse in the previous year or two 

or more relapses in the previous 2 years— 

ranging in age from 18–55 years. Patients 

were randomly assigned to receive either 

teriflunomide (7 mg or 14 mg), or placebo, 

once daily for 108 weeks. The primary end 

point was the annualized relapse rate, and 

the secon dary end point was confirmed progression 

of dis ability for at least 12 weeks. 

Compared with placebo, teriflunomide 

reduced the annualized relapse rate by 

31.2% and 31.5% in the 7 mg and 14 mg dose 

groups, respectively (P

NEUROLOGY 

In summary, research in 2011 conveyed 

new findings to help us to understand, treat 

and prevent disease progression in patients 

with MS. Better imaging of cortical lesions 

could provide insights into the patho biology 

of MS and may yield new outcome measures 

for MS clinical trials. Advances in understanding 

the environmental factors that are 

associated with disease progression in MS 

could facilitate the development of better 

therapies and personalized management for 

patients with this disabling disease. 

Jacobs Neurological Institute, Buffalo General 

Hospital, University at Buffalo, State University 

of New York, Building E, 2nd Floor, 100 High 

Street, Buffalo, NY 14203, USA 

(B. Weinstock‑Guttman). Department of 

Pharmaceutical Sciences and Neurology, State 

University of New York, 427 Cooke Hall, Buffalo, 

NY 14260, USA (M. Ramanathan). 

Correspondence to: B. Weinstock–Guttman 

bguttman@thejni.org 


The authors would like to thank the Department of 

Defense, the Jog for The Jake Foundation, National 

Multiple Sclerosis Society, National Science 

Foundation and NIH for providing financial support 

for their research activities. 


B. Weinstock–Guttman declares associations with 

the following companies and organizations: Acorda, 

Biogen Idec, Cyberonics, EMD Serono, Novartis, 

Pfizer, Teva Neuroscience. M. Ramanathan declares 

associations with the following companies and 

organizations: Allergan, the American Association of 

Pharmaceutical Scientists, Biogen Idec, EMD 

Serono, Netezza, Novartis, Pfizer. See the article 

online for full details of the relationships. 

1. O’Connor, P. et al. Randomized trial of oral 

teriflunomide for relapsing multiple sclerosis. 

N. Engl. J. Med. 365, 1293–1303 (2011). 

2. Sormani, M. P. et al. Modeling the distribution 

of new MRI cortical lesions in multiple 

sclerosis longitudinal studies. PLoS ONE 6, 

e26712 (2011). 

3. Weinstock‑Guttman, B. et al. Serum lipid 

profiles are associated with disability 

and MRI outcomes in multiple sclerosis. 

J. Neuroinflammation 8, 127 (2011). 

4. Weinstock‑Guttman, B., Zivadinov, R. & 

Ramanathan, M. Inter‑dependence of vitamin 

D levels with serum lipid profiles in multiple 

sclerosis. J. Neurol. Sci. 311, 86–91 (2011). 

5. Kappos, L. et al. A placebo‑controlled trial of 

oral fingolimod in relapsing multiple 

sclerosis. N. Engl. J. Med. 362, 387–401 

(2010). 

6. Calabrese, M., Filippi, M. & Gallo, P. Cortical 

lesions in multiple sclerosis. Nat. Rev. Neurol. 

6, 438–444 (2010). 

DEMENTIA IN 2011 

Microbleeds in dementia 

—singing a different ARIA 

Philip Scheltens and Jeroen D. C. Goos 

In 2011, researchers used imaging techniques to investigate 

brain microbleeds in patients with dementia and highlighted how lobar 

microbleeds could be used as a marker for amyloid pathology and for 

predicting mortality. New guidelines on the inclusion and exclusion 

of participants with microbleeds in anti-amyloid clinical trials were 

also published. 

Scheltens, P. & Goos, J. D. C. Nat. Rev. Neurol. 8, 68–70 (2012); published online 10 January 2012; 

doi:10.1038/nrneurol.2011.222 

Following initial reports of small dotlike 

lesions on gradient-echo MRI in the 

brains of patients with dementia (Figure 1), 

many investigators set out to describe 

the prevalence and incidence of these 

lesions—later designated as micro bleeds 

or microhemorrhages—in both healthy 

people and individuals with this condition. 

Prevalence rates varied from 10% in healthy 

elderly individuals to 60% in patients with 

vascular dementia. 1 Interest in these lesions 

peaked when the first cases of incident 

micro bleeds along with increased signal 

inten sity on fluid-attenuated inversion recovery 

imaging, thought to represent vaso genic 

edema, were reported in patients receiving 

amyloid-lowering therapy. During the 2010 

Inter national Conference on Alzheimer 

Disease (AD), turmoil ensued over a cautionary 

letter from the FDA, which suggested 

drastic cut-offs in randomized clinical trials 

of amyloid-lowering drugs, both in terms of 

excluding patients with a single microbleed 

and terminating the participation of patients 

who developed a new microbleed during 

the study. In response, a series of important 

papers regarding the detection, prevalence 

and clinical relevance of microbleeds 

in patients with dementia-related disease 

appeared in 2011, includ ing a consensus 

statement from an inter national working 

group that introduced new terminology. 

At the beginning of 2011, Cordonnier 

and van der Flier reviewed the available 

litera ture on brain microbleeds in patients 

with AD. 1 The authors suggested that 

these lesions were associated with amyloid 

pathology and may have a crucial role in the 

pathophysiology of AD. Microbleeds were 

proposed to represent a link between the 

amyloid cascade hypo thesis and the vascular 

hypothesis—both popular explanatory 

models for the pathogenesis of AD. Furthermore, 

the location of the microbleeds was 

suggested to indicate their underlying etiology: 

lobar microbleeds would presumably 

be associated with cerebral amyloid angiopathy 

(CAA), whereas microbleeds in deep 

brain regions would be associated with 

hypertensive vasculopathy and increased 

risk of vascular complications. The clinical 

implications of microbleeds in patients 

with dementia were also stressed. Besides 

an association with cognition, micro bleeds 

have been linked to mortality, especially in 

cases of multiple lesions, as described by 

Henneman et al. in a 2009 study. 2 These 

investigators did not, however, assess the 

cause of death in their patients. 

Throughout 2011—within months of 

publication of the review by Cordonnier 

and van der Flier 1 —reports were published 

on several studies that have substantially 

extended our knowledge on microbleeds 

in patients with dementia-associated diseases. 

The suggestion that micro bleeds 

were closely linked to amyloid pathology 

was supported by the findings of Yates et al. 

for the Australian Imaging, Bio markers 

and Lifestyle Study of Ageing Research 

Group. 3 They found that even in healthy 

con trols, lobar microbleeds (detected using 

3T susceptibility-weighted imaging [SWI]) 

were associated with higher amyloid burden, 

as seen on 11 C-Pittsburgh compound B (PiB) 

PET imaging. Moreover, PiB-positive scans 

were more prevalent in participants with 

multiple lobar microbleeds (86%) than 

in those with only one lobar microbleed 

(67%). In agreement with these findings, 

results from a study by Goos et al., 4 in which 

cerebro spinal fluid amyloid biomarkers were 

used to assess amyloid burden, confirmed 

the relationship between lobar microbleeds 

and amyloid pathology. 

Altmann–Schneider and colleagues 

studied the relationship between microbleeds 

and mortality (with assessment of 

the cause of death) in a population of 435 

elderly people with pre-existing vascular 

dis ease. 5 Individuals with more than one 

microbleed had a sixfold increase in the risk 


of stroke-related death compared with those 

with no lesions. The location of the lesions 

also affected the risk of poor clinical outcomes: 

compared with individuals without 

any lesions, patients with nonlobar microbleeds 

had a twofold increase in the risk of 

cardiovascular death, and indivi duals with 

probable CAA type (lobar) microbleeds had 

a sevenfold increase in the risk of strokerelated 

death. These findings support the 

hypothesis that microbleeds have separate 

etiologies depending on their location in 

the brain, 1 and may provide an indication 

for the use of anticoagulant treatment in 

patients with these lesions—in particular, 

those with lobar microbleeds. 

The importance of detecting microbleeds 

before and during clinical trials was underlined 

in an extensive review on amyloidrelated 

imaging abnormali ties (ARIA) by 

Sperling et al. for the Alzheimer’s Association 

Research Roundtable Work group. 6 

These imaging abnormalities, seen on MRI, 

are thought to represent a spectrum of ‘leaky 

vessels’ that occur following anti- amyloid 

immunization therapy. The working hypothesis 

was that vasogenic edema (now called 

ARIA-E) caused leakage only of proteinaceous 

fluids from the vessels, whereas 

microbleeding—under the new umbrella 

term ARIA-H (for hemorrhage)—caused 

more-extensive leakiness of the vessels 

that allowed blood cells to cross the blood– 

brain barrier. For patients in clinical trials, 

the presence of microbleeds at baseline 

may be a risk factor for developing ARIA, 


■ Lobar microbleeds in patients with 

dementia were found to be associated 

with high amyloid burden 3 

■ Microbleeds were shown to have 

different etiologies and associated risk 

of mortality on the basis of their location 

in the brain 5 

■ New terminology for amyloid‑related 

imaging abnormalties (ARIA) and a 

new cut‑off point for microbleeds in 

participants of amyloid‑modifying clinical 

trials were introduced 6 

■ Susceptibility‑weighted imaging showed 

enhanced sensitivity for detecting 

microbleeds compared with gradient‑ 

echo imaging, and may help in future 

for identifying associations between 

microbleeds and clinical outcomes 7 

■ Studies that compared imaging with 

histopathology of microbleeds suggest 

that further refinement of imaging 

techniques is required to accurately 

detect these lesions 8 

as the number of lobar lesions is assumed 

to correlate with the presence and severity 

of CAA. 

Given the uncertainty regarding the risk 

of ARIA and concerns about CAA severity, 

Sperling et al. recommended a cut-off value 

for the exclusion of participants in trials of 

amyloid-modifying therapies for AD at four 

microbleeds. 6 This new guideline allows for 

variability in imaging measurements and 

reflects the uncertainty regarding the clinical 

relevance of small numbers of microbleeds. 

The authors further stated that occurrence of 

new asymptomatic microbleeds in patients 

during trials should not auto matically disqualify 

them from receiving further treatment; 

however, owing to a lack of data, 

no exact cut-off for dis qualification could 

be given. As the authors stressed, counting 

of microbleeds is not an exact science, 

and the uncertainty is further complicated 

by the varying sensitivities of different MRI 

techniques for detecting these lesions. 

Reporting in Stroke in May 2011, Goos 

et al. 7 compared conventional gradient-echo 

imag ing with SWI to detect microbleeds in 

140 patients from a memory clinic, and 

also to determine whether microbleeds 

were associated with patient and clinical 

characteristics. As expected, use of the 

more-advanced SWI technique enabled 

identi fication of patients with microbleeds 

with a greater sensitivity than could be 

achieved with gradient-echo imaging (40% 

versus 23%). SWI also detected a higher 

num ber of microbleeds per patient than 

did gradient-echo imaging. However, the 

corre lation between lesion numbers, clinical 

out comes and other radiological outcomes 

was limited. The clinical relevance of microbleeds 

will probably depend more on their 

location and size, than on the total number 

of lesions per se. The authors concluded, 

therefore, that although new imaging techniques 

can show a higher number of lesions, 

conventional imaging methods can already 

detect the majority of clinically relevant 

lesions. New imaging methods might help 

in identifying any associations between 

lesions and clinical and radiological outcomes; 

however, these new techniques are 

in urgent need of validation. 

De Reuck et al. 8 made an interesting 

attempt to validate MRI findings with 

patho logy, as reported in Cerebrovascular 

Disorders. The researchers investigated 

20 post mortem brains from patients with 

AD with different cerebrovascular lesions. 

Images of 45 large sections of the cerebral 

hemi spheres, brainstem and cere bellum 

NEUROLOGY 

Figure 1 | Brain microbleeds on MRI. 

Numerous lobar microbleeds with sparing of 

the basal ganglia and thalamus, suggestive 

of severe cerebral amyloid angiopathy in a 

71‑year‑old patient with dementia with 

Lewy bodies. Image obtained using 

susceptibility‑weighted imaging at 3T. 

obtained using 7.0T T2*-weighted MRI 

were paired with images showing histological 

detection of hematomas and microbleeds. 

In the cortico- subcortical regions, 

the sensitivity, specificity, and positive and 

negative predictive values of T2* imaging 

to detect microbleeds were excellent. 

How ever, analysis of MRI alone resulted 

in an over estimation of microbleeds in 

the stria tum due to the presence of iron 

de posits that were, in fact, not related to 

real hemor rhages. Furthermore, 31% of T2* 

hypo signals in the deep white matter were 

shown to be vessels filled with post mortem 

thrombi. Judging from these findings, 

more studies are needed before we can fully 

understand the correlations between MRI 

and pathology in patients with AD. 

From this selection of studies published 

in 2011, we can conclude that lobar microbleeds 

are a marker for underlying amyloid 

patho logy, are associated with strokerelated 

mortality, and should be adequately 

investi gated in patients participating in 

anti- amyloid clinical trials. Optimizaton 

of imaging methods to detect microbleeds 

will be of the utmost importance, 

and emerging techni ques will need to be 

evaluated and calibrated using clinical and 

pathological correlates. 

VU University Medical Center, Alzheimer Center, 

Department of Neurology, De Boelelaan, 1118 

1081 HZ Amsterdam, The Netherlands 

(P. Scheltens, J. D. C. Goos). 

Correspondence to: P. Scheltens 

p.scheltens@vumc.nl 


NEUROLOGY 



1. Cordonnier, C. & van der Flier, W. M. Brain 

microbleeds and Alzheimer’s disease: innocent 

observation or key player? Brain 134, 335–344 

(2011). 

2. Henneman, W. J. et al. MRI biomarkers of 

vascular damage and atrophy predicting 

mortality in a memory clinic population. Stroke 

40, 492–498 (2009). 

3. Yates, P. A. et al. Cerebral microhemorrhage 

and brain β‑amyloid in aging and Alzheimer 

disease. Neurology 77, 48–54 (2011). 

4. Goos, J. D. C. et al. Microbleeds relate to 

altered amyloid‑β metabolism in Alzheimer 

disease. Neurobiol. Aging http://dx.doi.org/ 

10.1016/j.neurobiolaging.2011.10.026. 

EPILEPSY IN 2011 

Insights into epilepsy treatments 

and biomarkers 

Fernando Cendes 

Research published in 2011 identified important factors related to 

serious adverse effects of antiepileptic drugs and sudden unexpected 

death in epilepsy, along with a potential new treatment and a promising 

marker of epileptogenesis. Further advances in these areas are urgently 

needed to improve the lives of people with epilepsy. 

Cendes, F. Nat. Rev. Neurol. 8, 70–71 (2012); published online 10 January 2012; 

doi:10.1038/nrneurol.2011.223 

Epilepsy affects people of all ages, is 

highly prevalent, and can have a good 

out come with appropriate anti epileptic 

drugs (AEDs). However, seizures are 

often refractory to clinical treatment, with 

detrimental—and even life-threatening— 

consequences. 1 Unpredictable events, 

such as serious adverse effects of AEDs 

and sudden unexpected death in epilepsy 

(SUDEP), make this condition even harder 

to manage. The fact that epilepsy still carries 

a great stigma, with many people hiding 

their condition, hinders public awareness 

and, in addition, makes it more difficult for 

the condition to be recog nized as a serious 

public health problem, resulting in reduced 

availability of research resources compared 

with other common diseases. Despite such 

obstacles, however, considerable advances 

are being made on a number of fronts, as 

illustrated by several key papers published 

during 2011. 

Sudden unexpected death is 20 times 

more frequent in people with epilepsy 

than in the general population, but the risk 

factors identified for SUDEP have not been 

consistent across the literature. A recent 

study by Hesdorffer et al. has helped to identify 

groups of people with epilepsy who are 

5. Altmann–Schneider, I. et al. Cerebral 

microbleeds are predictive of mortality in the 

elderly. Stroke 42, 638–644 (2011). 

6. Sperling, R. A. et al. Amyloid‑related imaging 

abnormalities in amyloid‑modifying therapeutic 

trials: recommendations from the Alzheimer’s 

Association Research Roundtable Workgroup. 

Alzheimers Dement. 7, 367–385 (2011). 

7. Goos, J. D. C. et al. Clinical relevance of 

improved microbleed detection by 

susceptibility‑weighted magnetic resonance 

imaging. Stroke 42, 1894–1900 (2011). 

8. De Reuck, J. et al. Comparison of 7.0‑T T 2 *‑ 

magnetic resonance imaging of cerebral bleeds 

in post‑mortem brain sections of Alzheimer 

patients with their neuropathological 

correlates. Cerebrovasc. Dis. 31, 511–517 

(2011). 

‘‘ The currently available AEDs 

do not prevent or cure epilepsy, 

and are merely antiseizure 

medications 

at particular risk of SUDEP. 2 In this pooled 

analysis of four case–control studies, earlyonset 

refractory symptomatic epilepsy, frequent 

generalized tonic–clonic seizures, and 

use of AED polytherapy were all found to 

be significant risk factors for SUDEP. Such 

studies are extremely important for drawing 

attention to the need to achieve complete 

seizure control in people with epilepsy. 

The currently available AEDs do not 

prevent or cure epilepsy, and are merely 

antiseizure medications. This fact underscores 

our lack of knowledge about the 

exact mechanisms of seizure genesis and 

modes of action of AEDs. In this context, 

a paper by Jeon et al. 3 was another important 

publication in 2011. The researchers 

studied the effects of cell-free extract 

derived from human adipose stem cells 

(ASCs) on the acute and chronic phases of 

the pilocarpine epilepsy model in mice. 4 

’’ 

Pretreatment with the extract did not affect 

seizure susceptibility to pilocarpine, but it 

did reduce the number of EEG spikes in the 

acute phase, and subsequently diminished 

sponta neous recurrent seizures (SRS) in 

the chronic epileptic stage. 3 Furthermore, 

continuing treatment in the chronic epileptic 

stage suppressed or inhibited SRS and 

had a positive effect on animal behavioral 

tests. In addition, animals treated with the 

extract had less damage to blood–brain 

barrier integrity than did untreated controls. 

Interestingly, heat-treated ASC extract had 

no beneficial effect, suggesting the importance 

of cytosolic proteins in the positive 

effects of this agent. 

Studies have suggested that stem or 

precursor cells may rescue degenerating 

neurons by modulating the host environment 

via a chaperone-like mechanism, or 

by altering immune-like functions including 

inflammatory responses. 5 Thus, some 

cell-based therapies might rely more on a 

‘bystander’ mechanism involving secretion 

of soluble factors—such as cytokines 

and chemokines—than on replacement of 

damaged neurons by neurogenesis. 3 The 

ASC extract used by Jeon et al. may act by 

modulating inflammatory events during 

epileptogenesis. 3 

During 2011, important contributions 

were also made to our understanding of 

serious adverse effects of AEDs, including 

risks of allergic reactions and teratogenesis. 

6,7 Carbamazepine, one of the most 

important AEDs, causes various forms of 

hypersensitivity reaction, ranging from 

maculopapular exanthema to severe 

and potentially lethal conditions such as 

Stevens–Johnson syndrome and toxic epidermal 

necrolysis (SJS–TEN). In a key 

publication, McCormack et al. 6 showed 

that the presence of the HLA-A*3101 

allele is associated with carbamazepineinduced 

hypersensitivity reactions among 

Europeans. The overall prevalence of carbamazepine 

hypersensitivity is 5.0%; presence 

of the HLA-A*3101 allele increased the 

risk to 26.0%, whereas absence of the allele 

reduced the risk to 3.8%. Another HLA 

allele, HLA-B*1502, is strongly correlated 

with carbamazepine-induced SJS–TEN in 

Asian populations but not in Europeans. 8 

Another serious adverse effect of AEDs is 

the increased risk of malformations in the 

offspring of women who use these medications 

during pregnancy. Clear evidence is 

available that some AEDs, such as valproic 

acid, pose major risks of terato genesis, and 

the perception is that some of the newer 

AEDs, including lamotrigine, could be safer. 



■ Early‑onset refractory symptomatic 

epilepsy, frequent generalized tonic– 

clonic seizures, and use of antiepileptic 

drug (AED) polytherapy are all significant 

risk factors for sudden unexpected death 

in epilepsy 2 

■ A cell‑free extract from human adipose 

stem cells has antiseizure and 

antiepileptogenic effects in mice 3 

■ The HLA‑A*3101 allele is associated with 

carbamazepine‑induced hypersensitivity 

reactions among Europeans 6 

■ The risk of malformation in offspring of 

woman taking AEDs depends not only 

on the type of medication, but also on 

the AED dose and the parental history of 

congenital malformation 7 

■ Interictal high‑frequency oscillations 

measured with scalp electrodes can 

reliably delineate the seizure‑onset zone 

in patients with focal epilepsy 9 

In a recent important publication, Tomson 

et al. 7 compared the relative teratogenicity 

of four common AEDs—carbamazepine, 

pheno barbital, valproic acid and lamotrigine—on 

the basis of data from the EURAP 

epilepsy and pregnancy registry. The authors 

showed that the risk of major congenital malformations 

increased in a dose-dependent 

manner with all four assessed AEDs. Particularly 

high malformation rates were observed 

with valproic acid doses >1,500 mg per day. 7 

The treatment associ ated with the lowest rate 

of malforma tions—lamotrigine at a dose of 

1,000 mg per day). Valproic acid doses of 

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RHEUMATOLOGY 

RA IN 2011 

Advances in diagnosis, treatment and definition 

of remission 

Gerd R. Burmester 

Evidence presented in 2011 suggests that rheumatoid arthritis might comprise two separate diseases—each 

with different etiological underpinnings—and that kinase inhibitors could soon be added to the therapeutic 

armamentarium. Together with new definitions of remission, these advances could aid the development of 

personalized, treat-to-target strategies. 

Burmester, G. R. Nat. Rev. Rheumatol. 8, 65–66 (2012); published online 10 January 2012; doi:10.1038/nrrheum.2011.201 

Here, I discuss the progress that has been 

made in RA research over the past year, focusing 

on studies that have increased our understanding 

of the genetic basis of the disease, 

that have demonstrated the efficacy of new 

treatment modalities, and that have more 

clearly defined our current goal—the state 

of remission. 

The development of laboratory tests for the 

detection of anti-citrullinated protein antibodies 

(ACPAs) has been a major advance in 

the diagnosis of RA, and has been recog nized 

as such through inclusion of these assays in 

the most up-to-date American College of 

Rheumatology (ACR)–European League 

Against Rheumatism (EULAR) disease 

classi fication criteria. 1 However, why the 

immune system of patients with RA erroneously 

identifies endogenous citrullinated 

proteins as foreign or as molecular danger 

signals—sometimes mounting an enormous 

response directed at these antigens—remains 

an unsolved riddle. 

Despite our incomplete understanding of 

ACPAs, they have become a cornerstone in 

the diagnosis of RA. In 2011, Padyukov et al. 2 

went one step further when they questioned 

whether the presence or absence of ACPAs 

could be used to define two distinct subsets 

of RA or even two genetically- distinct diseases. 

The investigators attempted to answer 

this question by performing a genome-wide 

associ ation study to identify differences 

in risk allele frequency between patients 

with and without ACPAs. Analysis of single 

nucleotide polymorphisms (SNP) in ACPAnegative 

patients with RA revealed that no 

SNP tested achieved genome-wide significance 

in comparison with control individuals. 

2 However, in a case–case association 


■ Anti-citrullinated protein antibody (ACPA) 

status might define two different subtypes 

of rheumatoid arthritis (RA) with different 

underlying etiologies 2 

■ Kinase inhibitors continue to show 

promise in the treatment of RA, particularly 

tofacitinib, 5 a janus-associated kinase 

inhibitor 

■ The publication of remission criteria for RA 8 

will facilitate treat-to-target strategies and 

standardize the reporting of trial outcomes 

study between these ACPA-negative individuals 

with RA and ACPA-positive patients 

with RA, marked differences were identified 

in the HLA region. 2 Notably, only a few 

SNPs were shared between ACPA-negative 

and ACPA-positive disease, and these shared 

alleles provide only a minor contribution to 

the overall genetic risk of developing RA. 2 

These findings suggest that no obvious 

common denominator determines overall 

genetic susceptibility to RA when ACPAnega 

tive and ACPA-positive forms are considered 

together, but different risk alleles 

probably underlie development of each of 

these disease subsets. 

In contrast to ACPA-negative RA, ACPApositive 

RA was associated with variation 

in genes that have been linked to other 

auto immune diseases, such as type 1 diabetes 

and systemic lupus erythematosus. 2,3 

Further more, most of the genes associated 

with ACPA-positive RA, including PTPN22, 

CD40 and STAT4, are implicated in inflammatory 

pathways. The odds ratios for some 

of these genetic associations with RA were 

low; nevertheless these links could point to 

important mechanistic similarities and/or 

differences between RA and other inflammatory 

diseases. Increased understanding 

of the etiology of RA derived from such 

data could lead to the identification of new 

th erapeutic targets. 3 

That RA does indeed comprise ‘two diseases’, 

one ACPA-negative and one ACPApositive, 

now seems reasonable to conclude. 

This discovery will have important implications 

for the future management of this disorder, 

particularly for diagnosis and therapy. 

However, many important questions remain 

unanswered; chiefly, what value do ACPAs 

hold in the prediction of subsequent response 

to treatment? Prognostic value has been 

demon strated for B-cell-depletion therapy, 4 

but ACPAs seem to provide less or no information 

pertaining to the success of treatment 

of RA using cytokine blockade. 

Once a patient has been diagnosed with 

RA, whether ACPA-negative or ACPApositive, 

the next consideration is treatment 

of the disease. An extensive armamentarium 

of therapeutics is currently available 

for the treatment of RA; however, considerable 

unmet medical need still exists as 

some patients fail to respond to treatment, 

whereas many others suffer relapses after 

initially demonstrating clinical improvement. 

Many failures have been encountered with 

small molecule drugs targeted at proteins 

involved in signal transduction, both with 

regard to efficacy and toxicity. Never theless, 

some persistent researchers in industry and 

academia have continued to develop new 

agents, notably targeting tyrosine kinases. 

Comprehensive drug development programs 

are underway, the most advanced 

of which seems to involve tofacitinib—a 

Janus-associated kinase (JAK) inhibitor. 


RHEUMATOLOGY 

Treatment population Treatment options 

Treatment goal 

ACPA-positive 

ACPA-negative 

Figure 1 | Treatment flow in RA. After diagnosis, it might be important to further stratify a patient 

with RA according to ACPA status. A variety of treatment options then exist for RA. Tyrosine 

kinases represent promising new agents that might be efficacious in the treatment of RA. The 

ultimate aim of treatment is to induce a state of remission. Abbreviations: ACPA, anti-citrullinated 

protein antibodies; CRP, C-reactive protein; PtG, patient global assessment score; RA, rheumatoid 

arthritis; SDAI, simplified disease activity index; SJC, swollen joint count; TJC, tender joint count. 

Tofacitinib binds to and inhibits the important 

intracellular enzymes JAK1, JAK2 and 

JAK3, which are involved in immune cell activation, 

production of proinflammatory cytokines 

and cytokine signaling. A major step 

towards the introduction of tofacitinib to the 

clinic was made in 2011 with the publi cation 

of the results of a phase IIb, 24-week, doubleblind, 

randomized controlled trial of this 

compound by Fleischmann et al. 5 The patient 

populations enrolled in this study comprised 

indivi duals with RA and an inadequate 

response to DMARDs, who were assigned to 

receive monotherapy of various dosages of 

tofacitinib, the TNF inhibitor adalimumab or 

placebo. Treatment with tofacitinib resulted 

in a rapid clinical response, with ACR 20% 

improvement criteria (ACR20) response at 

week 12 ranging from 59.2% (5 mg) to 71.9% 

(15 mg), and the response was maintained at 

24 weeks. 5 By contrast, ACR20 was achieved 

by 22% of the placebo group and an adalimumab 

response rate of 35.9% was recorded 

—notably, the latter drug was also used 

as a monotherapy without metho trexate. 5 

Markedly improved ACR50 and ACR70 

responses as well as disease activity score in 

28 joints (DAS28) remission were observed 

for tofacitinib, compared with placebo. 5 The 

adverse events associated with tofacitinib 

treatment included urinary tract infections, 

diarrhea and anemia. 5 These data confirmed 

the efficacy of tofacitinib, and have led to the 

initiation of a large phase III program for this 

drug in patients with RA. 

Thus, the therapeutic options available to 

rheumatologists could soon be increased by 

the addition of new orally administered small 

molecules, especially when one con siders 

that fostamatinib, another tyrosine kinase 

inhibitor that targets spleen tyrosine kinase 

(Syk), has also demonstrated con siderable 

Glucocorticoids 

Conventional DMARDs 

Cytokine inhibition 

B-cell depletion 

Inhibition of costimulation 

Inhibition of tyrosine kinases 

Remission (de�ned by TJC, 

SJC, PtG and CRP [mg/dl] 

all ≤1, or SDAI ≤3.3) 

efficacy in RA. 6 Naturally, important questions 

remain unanswered, particularly with 

regard to long term safety in the ‘real world’, 

where these agents will be used in combination 

with a multitude of other drugs that treat 

comorbid diseases. Moreover, it remains to be 

seen whether doctors and patients will prefer 

60 tablets per month over a syringe that can 

be selfadministered once a week, or even 

once per month. 

The introduction of new treatment modalities, 

such as tofacitinib and fostamatinib, 

could help us to reach our current goal in 

RA therapy, namely a state of remission, 

particularly if a treat-to-target approach is 

used. 7 However, what does ‘remission’ really 

mean? Last year, a group of American and 

Euro pean experts came together to explore 

this important question and to generate a 

stringent definition of this state of minimal 

disease activity. 8 

On the basis of the evidence from large 

trials that analyzed the development of 

radiologically evident joint destruction 

or loss of function, the panel representing 

ACR–EULAR came up with a definition for 

remission, 8 in which a number of different 

individual disease activity measures are considered 

together. Using this approach, remission 

is said to be achieved when the number 

of tender and swollen joints, the level of CRP 

(mg/dl) and the patient global assessment 

score (0–10 scale) are all ≤1. 8 An alternative 

definition is an SDAI (simplified disease 

activity index) of not more than 3.3. 8 In clinical 

practice and in trials, these definitions 

have been applied successfully. 9,10 However, 

to achieve a patient global assessment of ≤1 

will be a challenge. Although the goals set 

by ACR–EULAR are demanding, the 2011 

remission criteria define clear targets for the 

management of patients with RA and will 

probably change our approach to treating this 

debilitating disease, especially immediately 

after onset. 

As a result of key breakthroughs made in 

2011, we are now able to define RA much 

more effectively, we could soon have new 

thera peutics at our disposal and we have clear 

goals to aim at when treating patients with 

this previously devastating disease (Figure 1). 

Hope fully, the progress made last year will 

improve patient care and lead to further 

evolution of the field in 2012 and beyond. 

Department of Rheumatology and Clinical 

Immunology, Charité-Universitätsmedizin 

Berlin, Charitéplatz 1, 10117 Berlin, Germany. 

gerd.burmester@charite.de 



companies: Abbott and Pfizer. See the article online 

for full details of the relationships. 

1. Aletaha, D. et al. 2010 rheumatoid arthritis 

classification criteria: an American College 

of Rheumatology/European League Against 

Rheumatism collaborative initiative. Ann. 

Rheum. Dis. 69, 1580–1588 (2010). 

2. Padyukov, L. et al. Epidemiological Investigation 

of Rheumatoid Arthritis (EIRA) study group. A 

genome-wide association study suggests 

contrasting associations in ACPA-positive 

versus ACPA-negative rheumatoid arthritis. 

Ann. Rheum. Dis. 70, 259–265 (2011). 

3. Stahl, E. A. et al. Genome-wide association 

study meta-analysis identifies seven new 

rheumatoid arthritis risk loci. Nat. Genet. 

42, 508–514 (2010). 

4. Chatzidionysiou, K. et al. Highest clinical 

effectiveness of rituximab in autoantibodypositive 

patients with rheumatoid arthritis and 

in those for whom no more than one previous 

TNF antagonist has failed: pooled data from 

10 European registries. Ann. Rheum. Dis. 

70, 1575–1580 (2011). 

5. Fleischmann, R. et al. Phase 2B dose-ranging 

study of the oral JAK inhibitor tofacitinib 

(CP690,550) or adalimumab monotherapy 

versus placebo in patients with active 

rheumatoid arthritis with an inadequate 

response to DMARDs. Arthritis Rheum. 

http://dx.doi.org/10.1002/art.33383. 

6. Weinblatt, M. E. et al. An oral spleen tyrosine 

kinase (Syk) inhibitor for rheumatoid arthritis. 

N. Engl. J. Med. 363, 1303–1312 (2010). 

7. Smolen, J. S. et al. T2T Expert Committee. 

Treating rheumatoid arthritis to target: 

recommendations of an international task 

force. Ann. Rheum. Dis. 69, 631–637 (2010). 

8. Felson, D. T. et al. American College of 

Rheumatology/European League Against 

Rheumatism provisional definition of remission 

in rheumatoid arthritis for clinical trials. Ann. 

Rheum. Dis. 70, 404–413 (2011). 

9. Shahouri, S. H. et al. Remission of rheumatoid 

arthritis in clinical practice. Application of the 

American College of Rheumatology/European 

League Against Rheumatism 2011 remission 

criteria. Arthritis Rheum. 63, 3204–3215 (2011). 

10. Klarenbeek, N. B. et al. Association with joint 

damage and physical functioning of nine 

composite indices and the 2011 ACR/EULAR 

remission criteria in rheumatoid arthritis. 

Ann. Rheum. Dis. 70, 1815–1821 (2011). 


JIA IN 2011 

New takes on categorization 

and treatment 

Alberto Martini 

In 2011, new treatment recommendations for juvenile idiopathic arthritis 

(JIA) were proposed, inroads were made towards understanding the 

heterogeneity of this disease, and data were presented demonstrating 

the potential efficacy of DMARD combination therapies for JIA treatment. 

These advances hold promise for improved management of JIA in 2012 

and beyond. 

Martini, A. Nat. Rev. Rheumatol. 8, 67–68 (2012); published online 10 January 2012; 

doi:10.1038/nrrheum.2011.198 

2011 has witnessed the publication of a 

number of important pieces of information 

that increase our understanding of juvenile 

idiopathic arthritis (JIA) hetero geneity, 

which guide treatment decisions and pave the 

way for future studies regarding the potential 

efficacy of combination therapies with 

inexpensive DMARDs. Here, I dis cuss these 

advances and their potential to improve the 

management of JIA throughout the world. 

JIA is not a defined disease, but rather 

an exclusion diagnosis encompassing all 

forms of arthritis with symptoms that onset 

before the age of 16 years, persist for more 

than 6 weeks, and for which the cause is 

unknown. In the absence of defined pathogenic 

underpinnings, attempts have been 

made to classify this collection of heterogeneous 

disorders into homogeneous, 

mutually exclusive subgroups on the basis 

of clinical and laboratory features. 1 Some of 

the official JIA categories developed by the 

International League Against Rheumatism 

(ILAR) 1 seem to represent distinct disease 

entities (systemic, polyarticular rheumatoid 

factor (RF) positive, enthesitis-related 

arthritis and oligoarticular), whereas others 

seem to define heterogeneous conditions 

(polyarticular RF-negative, psoriatic). 

In Western countries most individuals 

with JIA classified as oligoarticular belong to 

a well-defined subset of patients with disease 

that is charac terized by several common features: 

asymmetric arthritis; early onset of 

symptoms (before 6 years of age); female 

predominance; the presence of antinuclear 

anti bodies (ANA); high risk of developing 

chronic iridocyclitis; and associ ation with 

specific HLA alleles. However, on the basis of 

a 2003 literature review, 2 it was suggested that 

patients with the same disease—ANA positive, 

early-onset oligo articular JIA—could be 

included into several different JIA categories: 

oligo articular, polyarticular RF-negative 

or psoriatic. Therefore, patient age at onset 

of symptoms, the presence of symmetric or 

asymmetric arthritis, and ANA positivity 

were proposed as potentially more suitable 

criteria for disease classification than the 

number of joints involved or the presence 

of psoriasis. 2 

‘‘ 2011 has witnessed important 

new advances in the understanding 

and management of JIA... 

A key paper published by Ravelli et al. 3 in 

2011 provides strong evidence to support 

this hypothesis, particularly the potential 

use of ANA status in JIA categorization. 

In a retro spective study that enrolled 

more than 900 patients with JIA, this group 

compared the features of ANA-positive 

and ANA-negative individuals. Importantly, 

the authors provi ded a definition of 

ANA positivity: antibody titers of ≥1:160 

detected in ≥2 tests performed at least 

3 months apart. 3 Many other publications 

have neglected to define ANA positivity, 

which could provide a source of confusion. 

Ravelli and colleagues3 found that ANApositive 

patients, despite being classified 

under different ILAR-defined JIA categories, 

were similar in terms of age at dis ease onset, 

female-to-male ratio, and fre quency of 

asymmetric arthritis and irido cyclitis, independent 

of the number of joints involved or 

the presence of psoriasis. Perti nent in this 

respect are the findings of Barnes and coworkers. 

4 ’’ 

These investi gators studied gene 

expression in peripheral blood mononuclear 

cells of 104 patients with recent-onset JIA 

(39 with oligo articular JIA, 45 with polyarticular 

RF-negative disease and 20 with systemic 

JIA), as well as in cells from 56 healthy 

controls. Their results reveal that a B-cell 

gene expression signature charac terizes 

RHEUMATOLOGY 

patients with early-onset arthritis (≤6 years 

of age), indepen dent of the number of joints 

involved. 4 Of note, a different cluster of genes 

related to cellular immunity and myeloid 

cell lineages was expressed at higher levels 

in patients with late-onset oligo articular JIA 

compared with individuals with early-onset 

dis ease. 4 Thus, these data suggest that age at 

onset of symptoms can also be of relevance 

in unravel ing disease heterogeneity among 

patients with oligoarticular JIA. 

Taken together, the findings I have described 

strongly substantiate the hypo thesis 

that age at onset of disease and ANA positivity 

could be used to identify a homo genous 

subset of patients with JIA—patients who are 

currently included in multiple different JIA 

categories on the basis of the ILAR classification 

criteria. However, future studies need 

to investigate whether, as might be expected, 

patients with a B-cell signature and early 

disease onset are also ANA positive. 

Over the past decade, dramatic improvements 

in the treatment of JIA have been 

made. This progress has been made possible 

not only by the introduction of biologic 

agents to the clinic, but also by the implementation 

of the so called ‘pediatric rule’ 5 

by the FDA and the European Medicines 

Agency (EMA). This rule states that when 

the pharmaceutical industry attempts to register 

a new drug for any given adult dis ease, 

data must also be provided on the safety and 

efficacy of that drug in children—provided 

a pediatric form of the disease exist. This 

stipulation has opened up the opportunity 

for several randomized controlled trials 

with new biologic therapies to be performed 

in patients with JIA. 

The rapid advances made in the treatment 

of JIA have presented new thera peutic 

options and made the decision-making processes 

more complex for rheumatologists. 

Therefore, a major step forward was provided 

last year by the publication of the American 

College of Rheumatology (ACR)-endorsed 

2011 recommendations for the treatment of 


■ Age at disease onset and antinuclear 

antibody status seem to define a 

distinct category of juvenile idiopathic 

arthritis (JIA) 3 

■ New treatment recommendations for JIA 

are an important tool, 6 but will soon need 

to be updated 

■ Combination DMARD therapy might be 

more efficacious than methotrexate 

alone, 10 which could influence treatment 

of JIA worldwide 


RHEUMATOLOGY 

JIA. 6 They represent the first official treatment 

recommendations for JIA to be based 

on objective, validated methods, and have 

already been reviewed in this journal. 7 The 

term ‘recommendations’ was used, instead of 

‘guidelines’, to emphasize their nonprescriptive 

nature; the intended aim of the publication 

was to support, but not to dictate, 

the individual physician’s decision. The 

recommendations are based on a comprehensive 

list of clinical scenarios, in which 

hypothetical patients are categorized on the 

basis of different combinations of key clinical 

parameters rele vant to the decision-making 

process, such as disease activity and potential 

prognostic features. 

The ACR recommendations are a very 

useful tool, which can guide the treatment of 

patients with JIA, but will soon require updating 

given the rapid evolution of this field. 

Indeed, tocilizumab—an antibody against 

the IL-6 receptor that has now been approved 

for the treatment of systemic JIA by both the 

FDA and the EMA—is not considered in 

the recommendations. More over, trials are 

currently being performed in patients with 

systemic JIA that aim to investigate the efficacy 

of two IL-1 inhibitors, canakinumab (a 

monoclonal anti-IL-1 antibody) and rilonacept 

(the recombinant extracellular domain of 

the human IL-1 receptor); the results of these 

studies will soon be available, and will presumably 

provide important new information 

re garding treatment of this disease. 

Although the introduction of biologic 

therapies has represented a major advance 

in the treatment of JIA, the fact remains 

that the high costs associated with provision 

of these agents can be afforded only by 

the health care systems of a limited number 

of countries. 8 Around the world, most children 

with JIA have to rely on much less 

expensive drugs, such as methotrexate. 

Therefore, data regarding the efficacy of 

combination therapies comprising methotrexate 

and other synthetic DMARDs in 

compari son with metho trexate alone would 

be viewed with interest by rheuma tologists 

worldwide. However, in contrast to rheumatoid 

arthritis—a dis ease in which many trials 

have supported the over all superiority of 

combination DMARD therapy over methotrexate 

monotherapy 9 —data on combi nation 

DMARD therapy are lacking for JIA. 

Important findings supporting the potential 

efficacy of combination DMARD therapy 

in JIA were presented last year by Tynjälä 

et al. 10 The authors randomly assigned 59 

patients with early poly articular JIA to 

three treatment cohorts: infliximab plus 

methotrexate; methotrexate alone; or methotrexate, 

sulfa salazine and hydroxychloroquine 

in combination. The results of this 

trial showed that infliximab plus methotrexate 

was su perior to combination therapy and 

strikingly superior to methotrexate alone. An 

interest ing aspect of this study was, therefore, 

that synthetic DMARDs in combi nation 

seemed to be superior to metho trexate 

treatment alone, although the difference 

in effi cacy was not statistically significant. 

The study was, however, underpowered to 

show a signifi cant difference and the trend 

in favor of combination therapy was consistent 

for all the endpoints tested. Thus, these 

results strongly suggest that combination 

therapies with inexpensive synthetic drugs 

could prove superior to methotrexate alone 

in future studies with appropriate sample 

sizes. The funding of these potentially very 

relevant investigator-initiated randomized 

studies should represent a future priority for 

in ternational public funding bodies. 

2011 has witnessed important new advances 

in the understanding and manage ment of JIA, 

but much remains to be done. In the future, 

more accurate classification of patients with 

JIA will be possible and more effec tive treatments 

will become avail able, owing to the 

integration of clinical data with the results of 

research into dis ease pathogenesis. 

University of Genoa, Pediatria II e 

Reumatologia, Istituto G. Gaslini, Largo G. 

Gaslini 5, 16147 Genoa, Italy. 

albertomartini@ospedale-gaslini.ge.it 



1. Petty, R. E. et al. International League of 

Associations for Rheumatology classification 

of juvenile idiopathic arthritis: second revision, 

Edmonton, 2001. J. Rheumatol. 31, 390–392 

(2004). 

2. Martini, A. Are the number of joints involved 

or the presence of psoriasis still useful tools 

to identify homogeneous disease entities in 

juvenile idiopathic arthritis? J. Rheumatol. 

30, 1900–1903 (2003). 

3. Ravelli, A. et al. Antinuclear antibody-positive 

patients should be grouped as a separate 

category in the classification of juvenile 

idiopathic arthritis. Arthritis Rheum. 63, 

267–275 (2011). 

4. Barnes, M. G. et al. Biologic similarities based 

on age at onset in oligoarticular and 

polyarticular subtypes of juvenile idiopathic 

arthritis. Arthritis Rheum. 62, 3249–3258 

(2010). 

5. Hirschfeld, S. & Saint-Raymond, A. Pediatric 

regulatory initiatives. Handb. Exp. Pharmacol. 

205, 245–268 (2011). 

6. Beukelman, T. et al. 2011 American College 

of Rheumatology recommendations for the 

treatment of juvenile idiopathic arthritis: 

initiation and safety monitoring of therapeutic 

agents for the treatment of arthritis and 

systemic features. Arthritis Care Res. 

(Hoboken) 63, 465–482 (2011). 

7. Hashkes, P. J. Pediatric rheumatology: 

strengths and challenges of a new guide for 

treating JIA. Nat. Rev. Rheumatol. 7, 377–378 

(2011). 

8. Sawhney, S. & Magalhães, C. S. Paediatric 

rheumatology—a global perspective. Best 

Pract. Res. Clin. Rheumatol. 20, 201–221 

(2006). 

9. Ma, M. H., Kingsley, G. H. & Scott, D. L. 

A systematic comparison of combination 

DMARD therapy and tumour necrosis inhibitor 

therapy with methotrexate in patients with early 

rheumatoid arthritis. Rheumatology (Oxford) 

49, 91–98 (2010). 

10. Tynjälä, P. et al. Aggressive combination drug 

therapy in very early polyarticular juvenile 

idiopathic arthritis (ACUTE-JIA): a multicentre 

randomised open-label clinical trial. Ann. 

Rheum. Dis. 70, 1605–1612 (2011). 

SLE IN 2011 

Deciphering the role of NETs 

and networks in SLE 

Thomas Dörner 

From neutrophil extracellular traps to genetic networks that underlie the 

disease and new targeted therapies, important advances in 2011 improve 

our understanding of the pathogenesis of systemic lupus erythematosus 

and mark the beginning of our ability to treat it effectively. 

Dörner, T. Nat. Rev. Rheumatol. 8, 68–70 (2012); published online 10 January 2012; 

doi:10.1038/nrrheum.2011.200 

2011 was a year of achievements in systemic 

lupus erythematosus (SLE)—for advances 

in basic and clinical research, and the translation 

of these findings into daily clinical 

practice. After a decade of failures of some 

biologic therapies in SLE, the recog nition of 

particular cellular and cytokine pathways as 

involved in the pathogenesis has initiated a 

promising period of progress in this complex 

disease. Many excellent contributions were 

published in 2011, but a few studies deserve 

emphasis for providing new perspectives. 


Genetic 

predisposition 

Subphenotype 1 

■ HLA-DRB1*0301 

(DR3) 

■ Lupus nephritis 

Epigenetic 

modulation 


■ Cumulative genetic risk 

factor and anti-dsDNA 

■ Young age at onset, 

hematological disorders 

and absence of oral ulcers 

Genetic risk 

score 


■ Lack of known SLE 

susceptibility genes 

■ Malar or discoid 

rash, photosensitivity, 

serositis and 

neurologic disorders 

UV light 

Gender 

Smoking 

(Viral infections) 

Despite the accepted roles of autoreactive 

lymphocytes in adaptive immunity, 

re searchers are only just beginning to 

understand the important early events of 

immune activation within innate immunity. 

Chronic activation of plasmacytoid dendritic 

cells (pDCs) leads to increased IFN-α 

production, which stimulates autoreactive 

lympho cytes and reduces the activation 

threshold of auto reactive B cells. Crucially, 

several recent papers have addressed neutrophil 

function in SLE. Increased neutrophil 

turnover corre lates with interferon levels, 

suggesting a link between neutrophil activation 

and chronic pDC activation in SLE. 1 

Moreover, self nucleic acids (normally nonimmunogenic) 

incorporated within immune 

complexes can trigger Toll-like receptor 

(TLR)7 2 and TLR9 activation. 3 In 2004, a 

cell-death process distinct from necrosis and 

apoptosis was identified, 4 in which immunogenic 

self DNA–antimicrobial peptide complexes 

are released by dying neutrophils. This 

process, ‘NETosis’, involves extrusion into the 

extracellular space by activated neutro phils of 

large amounts of nuclear DNA, in the form 

of web-like structures called neutrophil extracellular 

traps (NETs). 4 NETs are abundantly 

released by neutrophils in patients with SLE. 

A key 2011 paper by Lande et al. 5 has 

addressed a number of puzzling issues of 

Abnormal innate 

immune activation 

Neutrophil 

CR 

HNP or 

LL37–NET 

DNA 

complex 

IFN-α 

production 

APC 

NETosis Plasmacytoid DC 

activation 

Macrophage 

In�ammatory response 

TLR 

FcR 

Abnormal activation of adaptive 

immunity with memory maintenance 

NETosis in SLE. The researchers found that 

sera from patients with SLE (in contrast with 

control sera) contained immune complexes 

of self DNA and antimicrobial cationic peptides 

LL37 (also known as cathelicidin) and 

human neutrophil peptide (HNP). These 

immunogenic complexes were protected 

from nuclease degradation, and interaction 

with Fcγ receptor IIa (FcγRIIa, encoded by 

FCGR2A) on pDCs led to their internalization 

and, ultimately, to pDC activation. 

More over, autoantibodies against LL37 and 

HNP enhanced NET formation and facilitated 

further pDC activation. 5 These data 

sup port the notion that dysregulation of this 

neutrophil-dependent pathway drives chronic 

pDC activation and autoimmunity in SLE. An 

important finding was that the composition of 

the immune complexes—in particular LL37– 

double-stranded (ds)DNA and LL37–HNP– 

dsDNA complexes—determined their fate: 

FcRγIIa-mediated endo cytosis. Thus, pDCs 

have a hitherto unknown ‘hidden’ receptor 

specificity that is not essentially related to 

speci fic immuno receptor binding. These 

findings provide insights into early immune 

perturbations in SLE and deepen our understanding 

of SLE patho genesis, as well as 

challenging a key concept in SLE: the selective 

specificity of the auto immune response 

against certain self antigens. 6 

RHEUMATOLOGY 

Myeloid DC 

Figure 1 | From NETs to disease networks in SLE. A proposed pathogenic model of SLE incorporating key findings from 2011. Firstly, three genetic 

subphenotypes of SLE have been identified (left panel), which might be under different epigenetic control. Next, understanding of abnormal innate 

and adaptive immunity in SLE (middle panel) has increased, in particular with the finding that NETosis of neutrophils leads to IFN-α production by 

pDCs. Finally, belimumab, which targets BAFF (a key cytokine in the adaptive immune response in SLE), has shown clinical efficacy. Abbreviations: 

APC, antigen-presenting cell; T 1 cell, type 1 T helper cell; NET, neutrophil extracellular trap; DC, dendritic cell; SLE, systemic lupus erythematosus. 

H 

SLE is complex and heterogeneous. 

Rheuma tologists have learned that finetuning 

diagnostic approaches and therapeutic 

decisions can substantially influence 

patient outcomes (exemplified by differentiating 

anti phospholipid syndrome from SLE). 

Genetic loci identified as risk loci for SLE susceptibility 

(HLA-DRB1, FCGR2A, PTPN22, 

IRF5 and STAT4, among others) are mostly 

related to immunological pathways (such 

as antigen presentation and IFN signaling). 

Nevertheless, whether patterns of multiple 

risk alleles in patients with SLE constitute specific 

genotypes that relate to particular clinical 

manifestations has not been t horoughly 

studied; the direct genetic and epigenetic networks 

that underlie SLE pathogenesis remain 

unclear (Figure 1). 

In the second 2011 paper highlighted here, 

Taylor et al. 7 undertook a compre hensive 

analysis of 22 genetic variants implicated 

in SLE pathogenesis. The most statistically 

significant individual risk alleles associated 

with SLE were HLA-DR3-IRF5 and 

FCGR2A-PXK (consistent with the findings 

by Lande et al., 5 which demonstrated the 

importance of FcγRIIa in pDC activation). 

Importantly, in addition to the characterization 

of SLE susceptibility loci, the researchers 

studied their relationship with disease characteristics. 

An interesting categorization of SLE 


T cell 

T H 1 

cell 

Co-stimulation 

BAFF 

B cell 

Belimumab 

BAFF-R 

Autoantibodies 

Immune complexes 

Complement consumption 

Plasma cell 

End-organ 

damage 

■ Nephritis 

■ Atherosclerosis 

■ Lung manifestations 

■ Scarring 

■ Vascular occlusions 

■ Dermatitis

RHEUMATOLOGY 


■ Neutrophil extracellular traps induce 

innate immunity early in systemic lupus 

erythematosus (SLE) and possibly 

activate the adaptive immune response 5 

■ Genetic studies identify certain SLE 

subtypes and simultaneously indicate 

distinct roles of epigenetic modulation 7 

■ Approval of belimumab—the first 

targeted therapy in SLE—translates 

insights into abnormalities of the 

immune system in SLE into the clinic 9 

subphenotypes emerged, on the basis of the 

strength of association of each manifestation 

with known genetic susceptibility loci, and 

a genetic risk score. Thus, subphenotype 1 

is closely associated with HLA-DRB1*0301 

(DR3) and lupus nephritis, with ITGAM 

alleles protecting against arthritis; subphenotype 

2 is closely associated with cumulative 

genetic risk factors and is characterized by 

anti-dsDNA autoantibodies, immunological 

abnormalities, young age at onset, hematological 

disorders and absence of oral ulcers; 

and subphenotype 3—not associated with 

any known SLE risk loci (perhaps reflecting 

susceptibility to environmental or epigenetic 

modulation)—is characterized by malar or 

discoid rash, photosensitivity, serositis and 

neurological disorders. 

These interesting data highlight two major 

aspects of SLE genetics: first, the existence 

of distinct phenotypes based on different 

ge n etics, each associated with particular 

morbid ity and mortality risks; the other, 

that epi genetic modification probably differs 

between the hypothetical subphenotypes. 

However, the data cannot be extrapolated to 

different ethnic backgrounds; the participants 

were almost exclusively of European ancestry. 

Finally, in 2011 Navarra et al. 9 reported the 

phase III trial of belimumab, a new cytokinetargeted 

therapy for SLE—aimed, one could 

say, at disrupting the pathogenic ‘net work’ 

of the disease. A number of cytokine perturbations 

have previously been iden tified 

in patients with SLE, mainly comprising 

increased levels of B-cell activating factor 

(BAFF; TNF superfamily member 13B, 

also known as BLyS) and type I interferons. 

Belimumab, which blocks soluble BAFF, is 

a welcome step in improving SLE therapy 

—now approved by the FDA and European 

Medical Agency, it is the first targeted 

therapy directed at B cells in SLE, in a disease 

known to involve hyper active B lympho cytes. 

Importantly, the 2011 BLISS-52 trial 9 did 

not study the efficacy of beli mumab in only 

severe SLE; its success in a hetero geneous 

SLE population needed a large effects size 

to differentiate the results from placebo. 

Nonetheless, the drug was of insufficient 

potency to show a strong effect early in 

disease. That response to beli mumab might 

differ between the SLE sub phenotypes discussed 

above is probable. As the frequency of 

ANA-positivity was 92–95% among phase III 

participants, 9 compared with 66.7–74.3% 

in a previous phase II trial, 10 the benefit 

of belimumab for ANA-negative patients 

remains unclear. Furthermore, identifying 

the specific profile of belimumab respon ders 

could improve understanding of the distinct 

immuno pathologies of SLE sub phenotypes 

and lead to more effective therapeutic 

de cisions by tailoring therapy to each patient. 

Overall, from NETs to disease networks, 

studies published in 2011 collectively open 

new avenues of investigation in SLE, including 

early innate activation paths, delineation 

of subsets (with genetic profiles probably 

complemented by epigenetic modifications) 

and the identification of therapeutic 

responders to belimumab. Thus, basic and 

clinical research support re-evaluation SLE 

in terms of better defined subtypes. 

Department of Medicine, Rheumatology and 

Clinical Immunology, Charite Center 12, Charite 

Universitätsmedizin Berlin and Deutsches 

Rheumaforschungszentrum, Chariteplatz 01, 

10098 Berlin, Germany. 

thomas.doerner@charite.de 



1. Craft, J. Dissecting the immune cell mayhem 

that drives lupus pathogenesis. Sci. Transl. 

Med. 3, 73ps9 (2011). 

2. Rubtsov, A. V. Toll-like receptor 7 (TLR7)-driven 

accumulation of a novel CD11c + B-cell 

population is important for the development of 

autoimmunity. Blood 118, 1305–1315 (2011). 

3. Leadbetter, E. A. et al. Chromatin-IgG 

complexes activate B cells by dual engagement 

of IgM and Toll-like receptors. Nature 416, 

603–607 (2002). 

4. Brinkmann, V. et al. Neutrophil extracellular 

traps kill bacteria. Science 303, 1532–1535 

(2004). 

5. Lande, R. et al. Neutrophils activate 

plasmacytoid dendritic cells by releasing 

self-DNA-peptide complexes in systemic lupus 

erythematosus. Sci. Transl. Med. 3, 73ra19 

(2011). 

6. Dörner, T., Giesecke, C. & Lipsky, P. E. 

Mechanisms of B cell autoimmunity in SLE. 

Arthritis Res. Ther. 13, 243 (2011). 

7. Taylor, K. E. et al. Risk alleles for systemic 

lupus erythematosus in a large case–control 

collection and associations with clinical 

subphenotypes. PLoS Genetics 7, e1001311 

(2011). 

8. Lindh, E. et al. AIRE regulates T-cell-independent 

B-cell responses through BAFF. Proc. Natl Acad. 

Sci. USA 105, 18466–18471 (2008). 

9. Navarra, S. V. et al. Efficacy and safety of 

belimumab in patients with active systemic 

lupus erythematosus: a randomised, placebocontrolled, 

phase 3 trial. Lancet 377, 721–731 

(2011). 

10. Wallace, D. J. et al. A phase II, randomized, 

double-blind, placebo-controlled, dose-ranging 

study of belimumab in patients with active 

systemic lupus erythematosus. Arthritis 

Rheum. 61, 1168–1178 (2009). 

OA IN 2011 

Age-related OA—a concept 

emerging from infancy? 

Thomas Aigner and Wiltrud Richter 

That primary osteoarthritis (OA) is an age-related disorder is undoubted, 

but how aging contributes to OA is poorly understood. New insights 

from 2011 offer potential explanations, novel models for study, and the 

suggestion that a deeper understanding of what ‘aging’ actually is might 

pave the way to everlasting joints. 

Aigner, T. & Richter, W. Nat. Rev. Rheumatol. 8, 70–72 (2012); published online 10 January 2012; 

doi:10.1038/nrrheum.2011.206 

Aging is the most prominent risk factor for 

the initiation and progression of pri mary 

OA. Many explanations for this phe-nomenon 

have been suggested over time, 1 

without conclusion. In fact—although 

the concepts underlying them might be 

largely correct—the details of these opposing 

theories might have obscured the 

true nature of what ‘aging’ is in relation 

to OA. 

The most longstanding theory of the 

pathogenesis of primary OA (if one takes 

the articular cartilage as the starting point) 

involves the cumulative effects of continuous 

mechanical wear and tear on the 

articu lar cartilage matrix during a lifetime 

of joint use (Box 1). A second theory is 

related to well known age-related intrinsic 

changes in the extracellular matrix of 

articular carti lage, such as collagen network 


stiffen ing and the formation of advanced 

glycation end products. A third, frequent 

explanation for OA cartilage degeneration 

is the mere loss of viable cells (due to apoptosis 

or any other mechanism of cell death), 

as cellular replenish ment does not occur in 

articular cartilage. 

We and others have suggested that OA 

is a consequence of (premature) aging of 

chondrocytes in joint tissues (cell senescence 

theory, Box 1). Although not dead, 

senescent cells nevertheless lose their capacity 

to sustain the cartilage matrix, which 

can trigger an osteoarthritic degeneration 

pathway. 2–4 As we discuss below, chondrocyte 

behavior seems to change with increasing 

age: the cells respond less well to growth 

factors, and anabolic activity declines. In 

2011, Loeser and colleagues 5 went some 

way towards unpicking what OA-related 

cellular aging actually looks like at the 

level of gene expression. Their interest ing 

functional genomic study targeted gene 

expression alterations in a surgical meniscus 

destabilization mouse model of OA, 

and examined test animals of different 

ages. As well as disease-related changes, the 

investigators also observed substantial differences 

in the injury-induced patterns of 

expression between ‘young’ and ‘old’ mice, 

in chondrocytes, meniscal cells and other 

joint tissues. 5 Genes involved in matrix production, 

immunity and defense were among 

those affected, but our current knowledge of 

chondrocyte cell biology—whether young 

or aging—is not detailed enough to explain 

the differences observed. Nonetheless, this 

finding clearly shows that cartilage cells 

react differently depending on their aging 

status, a phenomenon also documented for 

mesenchymal progenitor cells. 6 

Articular cartilage is especially vulnerable 

to the effects of cellular aging and senescence. 

At skeletal maturity, sub chondral 

cal cification isolates the tissue from the 

vas cular system such that no new cells can 

enter the articular cartilage. Chondrocytes 

become postmitotic—they cease proliferation 

and are thus among the oldest cells of 

the human body, able to survive for decades 

without replacement. Furthermore, they 

are constrained within the cartilage matrix, 

unable to move. Even when chondro cytes 

start to divide again, as occurs in OA cartilage, 

cells from one site are, there fore, unable 

to replace damaged or absent cells elsewhere, 

except for those literally adjacent. 

One consequence of this postmitotic status 

is that oxidatively damaged molecules (proteins, 

DNA, lipids) accumulate in articular 

Box 1 | Aging theories in the pathogenesis of OA 

chondrocytes with aging, as these molecules 

are not completely re- synthesized within 

the cells, as would occur during cell division. 

This accumulation of damaged molecules 

impairs the ability of chondrocytes 

to remain functional and maintain tissue 

homeostasis. More importantly, the senescent 

cellular phenotype alters how cells 

react to stimuli. Indeed, our conception of 

the laws of cellular organization and function 

in relation to age is evolving rapidly in 

the 21st century. 7 

Thus, the most important implications of 

this emerging aging concept in OA development 

might be that the biology of cellular 

degeneration is part of the basis for the initiation 

and progression of OA. Furthermore, 

this knowledge emphasizes that whatever 

treatment of OA we envisage, we must take 

into account that we are dealing with aged 

and senescent or pre-senescent cells that 

no longer have the abilities of their juvenile 

counterparts to counteract mechanical, 

inflammatory, and/or other insults to 

the tissue. This previously insufficiently 

appreciated requirement might be one core 

explanation why many promising therapeutic 

approaches, established and tested 

in ‘juvenile’ cell lines and animal models, 

have subsequently failed in aged human OA 

cartilage in vivo. 

Is the only way to investigate these agerelated 

effects to wait until individuals 

age—which is rather a long time in the 

con text of most experiments—or can we 

find quicker, informative model systems? 

RHEUMATOLOGY 

Continuous loading theory 

Osteoarthritis (OA) results from the cumulative effects of continuous mechanical wear and tear 

on cartilage; thus ‘aging’ is simply the accumulation of loading cycles over a lifetime of joint use. 

Matrix pathobiochemistry theory 

OA results from age-related changes in the extracellular matrix of articular cartilage: 

■ Collagen network stiffening due to increased covalent cross-linking 

■ Altered expression of aggrecan molecules that account for the enormous swelling capacity 

of articular cartilage and, thus, its resistance to compression 

■ The formation of advanced glycation end products affects matrix integrity and chondrocyte 

biology 

Progressive (apoptotic) cell loss theory 

OA results from the loss of viable cells, due to apoptosis or any other mechanism of cell death, 

at the beginning of and during the disease process. As chondrocytes are solely responsible 

for replenishing the articular matrix, substantial loss of these cells results in the loss and 

degeneration of the surrounding matrix. 

Mitochondrial degeneration theory 

OA results from the continuous degeneration of chondrocyte mitochondria that eventually leads 

to energy failure as well as high oxidative stress in the cells. 

Cell (pre)senescence theory 

OA results form the inability of the cells to maintain tissue homeostasis (in particular after 

insults of a mechanical or inflammatory nature) due to cellular degeneration and/or aging 

caused in part by the accumulation of oxidatively-damaged molecules. 


■ Gene expression changes in joint tissue 

of older mice hint at how age and injury 

interact in OA 5 

■ Oxidative stress ages human chondrocytes 

in vitro, 8 which might provide a model for 

studying age-related OA development 

■ Cartilage senescence is delayed by growth 

inhibition, 10 indicating that cellular ‘aging’ 

might be uncoupled from time itself 

Taking chondrocytes from the replaced 

joints of patients with OA is of limited 

practical use; isolating diseased chondrocytes 

is a difficult endeavor with low 

yields. More troublesome still is the suspicion 

that one might only sample the more 

healthy subpopulation of cells and not the 

really diseased ones, which would explain 

the low yields of isolated cells per gram 

of tissue (in fact, most OA chondrocytes 

are lost during the isolation procedure). 

Quicker in vitro model systems are clearly 

required. Poten tially help ful, therefore, is 

the 2011 report by Brandl and colleagues 8 

of an in vitro model of aging of chondrocytes. 

Chondrocytes are unique in their 

avascular setting, and the effect of oxidative 

stress on these cells is not well characterized. 

Brandl et al. 8 found that oxidative 

stress accelerated cellular aging in chondrocytes—and 

can thus be used to artificially 

induce ‘age’ in cell culture—and that 

senescent chondrocytes are less resistant 

to oxidative stress. Similar strategies might 

be adapted to in vivo models, evading the 


RHEUMATOLOGY 

usually unfeasible requirement of waiting 

for the natural aging of test animals. 

Another potentially interesting in vivo 

study system was also advanced in 2011, 

and has furthered our understanding of 

aging in cartilage. Baron and colleagues 

have, 9 for several years now, studied 

senescence in fetal growth plate cartilage, 

previously finding it to be delayed as a consequence 

of hypothyroidism; once the deficiency 

is resolved, new, ‘catch-up’ growth 

results. In 2011, the group showed that 

cartilage senescence is delayed by general 

growth inhi bition; 10 thus, the onset of senescence 

is not governed by time, but rather by 

growth. These findings are further support 

for the notion that a time- dependent wear 

process might be insufficient to explain the 

onset of OA. Nevertheless, whether growthplate 

cartilage reflects substantial aspects 

of OA chondrocyte senescence and, thus, 

can contribute substantially to OA and 

chondrocyte aging research remains to 

be examined. 

OA and OA research is increasingly leaving 

behind the simple age-related fatalistic 

concept of chronic wear and tear, that 

is, matrix and cell degeneration. The concept 

of aging as a phenomenon with its 

own biology needs to be understood by the 

OA community as a new, innovative and 

excit ing area of chondrocyte and carti lage 

research. Though recent advances leave one 

with the impression that our understanding 

in this regard remains in its infancy, 

the emerging data might help to push OA 

research from a niche of orthopedic interests 

to a highly topical research area: what 

human aging means, in terms of biological 

processes, and what we can do about 

it. OA research might merge with the everexpanding 

search for the Holy Grail, or to 

speak with a German tongue, the ‘Jungbrunnen’ 

(fountain of youth). In the case 

of OA research and patient management, 

the result would be ever-functioning, 

painless joints. 

Institute of Pathology, Medical Center Coburg, 

Ketschendorferstraße 33, 96450 Coburg, 

Germany (T. Aigner). Research Centre for 

Experimental Orthopedics, Heidelberg 

University Hospital, Schlierbacher Landstraße 

200a, 69118 Heidelberg, Germany (W. Richter). 

Correspondence to: T. Aigner 

thomas.aigner@klinikum-coburg.de 


We acknowledge the support of the DFG for our work 

(grant numbers Ai 20/7-1,2 and Ri 707/7-1). 



1. Aigner, T., Rose, J., Martin, J. & Buckwalter, J. 

Aging theories of primary osteoarthritis: 

from epidemiology to molecular biology. 

Rejuvenation Res. 7, 134–145 (2004). 

2. Aigner, T., Söder, S., Gebhard, P. M., 

McAlinden, A. & Haag, J. Mechanisms 

of disease: role of chondrocytes in the 

pathogenesis of osteoarthritis—structure, 

chaos and senescence. Nat. Clin. Pract. 

Rheumatol. 3, 391–399 (2007). 

3. Martin, J. A., Ellerbroek, S. M. & 

Buckwalter, J. A. Age-related decline in 

chondrocyte response to insulin-like growth 

factor-I: the role of growth factor binding 

proteins. J. Orthop. Res. 15, 491–498 

(1997). 

4. Loeser, R. F. Aging and osteoarthritis: the role 

of chondrocyte senescence and aging changes 

in the cartilage matrix. Osteoarthritis Cartilage 

17, 971–979 (2009). 

5. Loeser, R. F. et al. Microarray analysis reveals agerelated 

differences in gene expression during the 

development of osteoarthritis in mice. Arthritis 

Rheum. http:dx.doi.org/10.1002/art.33388 

6. Dexheimer, V., Mueller, S., Braatz, F. & 

Richter, W. Reduced reactivation from 

dormancy but maintained lineage choice 

of human mesenchymal stem cells with donor 

age. PLoS ONE 6, e22980 (2011). 

7. Kirkwood, T. B. Understanding the odd science 

of aging. Cell 120, 437–447 (2005). 

8. Brandl, A. et al. Oxidative stress induces 

senescence in chondrocytes. J. Orthop. Res. 

29, 1114–1120 (2011). 

9. Lui, J. C., Nilsson, O. & Baron, J. Growth plate 

senescence and catch-up growth. Endocr. Dev. 

21, 23–29 (2011). 

10. Forcinito, P. et al. Growth-inhibiting conditions 

slow growth plate senescence. J. Endocrinol. 

208, 59–67 (2011). 

SSC IN 2011 

From mechanisms to medicines 

Luc Mouthon 

Findings from ongoing studies of imatinib in systemic sclerosis (SSc) 

were eagerly awaited in 2011, but results from these clinical trials have 

so far been disappointing. However, progress in the understanding of the 

mechanisms that underlie SSc pathogenesis could provide clues to novel 

targets for 2012 and beyond. 

Mouthon, L. Nat. Rev. Rheumatol. 8, 72–74 (2012); published online 10 January 2012; doi.10.1038/ 

nrrheum.2011.203 

Systemic sclerosis (SSc) is a connective 

tissue disorder characterized by excessive 

collagen deposition in the dermis and 

inter nal organs, vascular hyper-reactivity 

and vascular obliteration. Tissue fibrosis 

results from the increased release of extracellular 

matrix from aberrantly activated 

fibroblasts. 1 This accumulating extra cellular 

matrix disrupts the physiological tissue 

structure, leading to organ dys function, 

which contributes to the high morbidity 

and increased mortality in patients with 

SSc. However, the mechanisms underlying 

pathological fibroblast activation are 

incompletely understood. Transforming 

growth factor β (TGF-β) seems, however, 

to be a master regulator of both physiological 

and pathological matrix remodeling, 

and might be responsible for maintaining 

the activated fibroblast phenotype in SSc. 1 

Although a number of therapeutic trials 

have been conducted with antifibrotic 

agents (including d-penicillamine, relaxin, 

IFN-α and IFN-γ) in patients with SSc, 

none had a major therapeutic effect. Here, 

I will highlight the results of recent clinical 

studies of imatinib (a new antifibrotic 

agent) in patients with SSc and the latest 

advances in understanding the mechanisms 

of fibrosis in SSc. 2011 has been a year of 

progress, but will new mechanistic insights 

lead to new medicines for SSc? 

Understanding of fibrosis in SSc has 

already led to trials of new therapies that 

might control the disease. An example 

being imatinib mesylate, a tyrosine kinase 

inhibi tor already approved for the treatment 

of chronic myelogenous leukemia. 

Imatinib binds to c-Abl (an important 

down stream signaling molecule of TGF-β) 

and blocks its tyrosine kinase activity, 2 as 

well as interfering with platelet-derived 

growth factor signaling. In an in vitro 

model of bleomycin- induced pulmonary 

fibrosis, c-Abl inhibition by imatinib prevented 

TGF-β-induced extracellular matrix 

component gene expression, transformation 

and proliferation of fibroblasts. 3 Similar 

results were seen in mouse models of dermal 

fibrosis in SSc. 4 These interesting results led 

a number of investigators to launch clinical 

studies to examine the effectiveness of imatinib 

as an SSc therapy, the findings of which 

were eagerly anticipated. Of the six trials 

testing the efficacy of imatinib registered 

on ClinicalTrials.gov, four have been completed; 

findings from three of these studies 

were published in 2011, while the results of 


the fourth are not yet available. Moreover, 

two other studies of different tyrosine kinase 

inhibitors are ongoing in patients with SSc: 

one open-label phase IIa study using nilotinib 

and another open-label phase I/II study 

using dasatinib. 

‘‘ …will new mechanistic 

insights lead to new medicines 

for SSc? 

’’ 

Results from the imatinib trials published 

in 2011 were somewhat disappointing in 

terms of the tolerance and efficacy of the 

drug. Spiera et al. 5 conducted a phase IIa, 

open-label, single-arm clinical trial in 30 

patients with diffuse SSc who were treated 

with imatinib (400 mg per day) over 

12 months. Mean Rodnan skin score (MRSS) 

decreased by 6.6 points (or by 22.4%) at 

12 months (P = 0.001). 5 Pulmonary function 

was also tested, with forced vital capacity 

(FVC) improving by 6.4% predicted 

(P = 0.008), whereas the diffusion capacity 

remained stable. 5 Six patients withdrew from 

the study, two because of non compliance, 

four because of adverse events (including 

one who died after 11 months). 5 In total, 171 

adverse events of various grades were identified, 

the most common being edema, which 

was observed in 80% of patients. 24 serious 

adverse events were identified, two of which 

were attributed to the study medication. 5 The 

authors concluded that imatinib has acceptable 

safety and toler ability, and suggest it has 

potential efficacy for cutaneous and pulmonary 

manifestations of SSc. 5 However, other 

studies did not replicate these findings. 

In their phase I/IIa pilot study, Khanna 

and colleagues 6 recruited 20 patients with 

SSc-related interstitial lung disease (ILD) 

who had FVC 0.05) and MRSS 

(of 3.9 units; P

RHEUMATOLOGY 

fibrosis and ameliorated established fibrosis. 

9 Consistent with these findings, mice 

deficient in tryptophan hydroxylase 1—the 

rate-limiting enzyme for 5-HT production 

outside the central nervous system—had 

reduced experimental skin fibrosis. 9 These 

findings, together with recent results from 

5-HT receptor antagonists in experi mental 

pulmonary or liver fibrosis, suggest that 

5-HT–5-HT 2B receptor signaling links 

vascular damage and platelet activation to 

tissue remodeling, and highlight the 5-HT 2B 

receptor as a novel therapeutic target to treat 

fibrotic diseases. 

In summary, blocking extrinsic coagulation 

system and/or platelet activation might 

represent promising future strategies for SSc 

treatment. From mechanisms to new medicines, 

research in 2011 has made tenta tive 

steps to providing an effective targeted 

therapy for SSc. Although the efficacy of 

imatinib has not yet been confirmed, 

mecha nistic insights into the development 

of fibrosis in SSc have provided vital 

clues for the development of new drugs for 

this challenging disease and trials of new 

therapies are ongoing. 

Université Paris Descartes, Faculté de 

Médecine, Service de Médecine Interne, 

Hôpital Cochin, 27 rue du Faubourg Saint 

Jacques, 75014 Paris, France. 

luc.mouthon@cch.aphp.fr 



companies: Actelion, GlaxoSmithKline, Lilly, Pfizer. 

See the article online for full details of the 

relationships. 

1. Bhattacharyya, S., Wei, J. & Varga, J. 

Understanding fibrosis in systemic sclerosis: 

shifting paradigms, emerging opportunities. 

Nat. Rev. Rheumatol. http://dx.doi.org/ 

10.1038/nrrheum.2011.149. 

2. Distler, J. H. & Distler, O. Imatinib as a novel 

therapeutic approach for fibrotic disorders. 

Rheumatology (Oxford) 48, 2–4 (2009). 

3. Aono, Y. et al. Imatinib as a novel antifibrotic 

agent in bleomycin-induced pulmonary fibrosis 

in mice. Am. J. Respir. Crit. Care Med. 171, 

1279–1285 (2005). 

4. Distler, J. H. et al. Imatinib mesylate reduces 

production of extracellular matrix and 

prevents development of experimental dermal 

fibrosis. Arthritis Rheum. 56, 311–322 

(2007). 

5. Spiera, R. F. et al. Imatinib mesylate 

(Gleevec) in the treatment of diffuse 

cutaneous systemic sclerosis: results of a 

1-year, phase IIa, single-arm, open-label 

clinical trial. Ann. Rheum. Dis. 70, 1003–1009 

(2011). 

6. Khanna, D. et al. A one-year, phase I/IIa, 

open-label pilot trial of imatinib mesylate in the 

treatment of systemic sclerosis-associated 

active interstitial lung disease. Arthritis Rheum. 

63, 3540–3546 (2011). 

7. Pope, J. et al. Imatinib in active diffuse 

cutaneous systemic sclerosis: results of a 

six-month, randomized, double-blind, placebocontrolled, 

proof-of-concept pilot study at a 

single center. Arthritis Rheum. 63, 3547–3551 

(2011). 

8. Chrysanthopoulou, A. et al. Tissue factorthrombin 

signaling enhances the fibrotic 

activity of myofibroblasts in systemic sclerosis 

through up-regulation of endothelin receptor A. 

Arthritis Rheum. 63, 3586–3597 (2011). 

9. Dees, C. et al. Platelet-derived serotonin links 

vascular disease and tissue fibrosis. J. Exp. 

Med. 208, 961–972 (2011). 

10. Postlethwaite, A. E. & Chiang, T. M. Platelet 

contributions to the pathogenesis of systemic 

sclerosis. Curr. Opin. Rheumatol. 19, 574–579 

(2007). 

VASCULITIS IN 2011 

The renaissance of granulomatous 

inflammation in AAV 

Stephan D. Gadola and Wolfgang L. Gross 

In 2011, the year that subtypes of ANCA-associated vasculitis (AAV) were 

officially renamed according to key pathological characteristics, important 

progress was made not only in differentiating these subtypes, but also in 

understanding—and treating—their eponymous manifestations. 

Gadola, S. D. & Gross, W. L. Nat. Rev. Rheumatol. 8, 74–76 (2012); published online 10 January 2012; 

corrected online 24 January 2012; doi:10.1038/nrrheum.2011.218 

Granulomatosis with polyangiitis (GPA, formerly 

Wegener´s granulomatosis), Churg- 

Strauss syndrome (CSS) and microscopic 

polyangiitis (MPA) constitute the antineutrophil 

cytoplasmic antibody (ANCA)associated 

vasculitides (AAV), forms of 

primary small-vessel vasculitis associated 

with ANCA seropositivity. Owing to the 

rarity of their disease, patients with dif ferent 

AAV are often pooled in clinical trials. Disease 

evolution, organ involvement, prognosis, 

and other parameters , however, dif fer 

substantially between GPA, CSS and MPA, 

although the mechanistic bases for these 

differences remain largely unexplored. To 

unravel them, effective classification of 

patients with AAV is essential, beginning 

with defining—and naming—the subtypes. 

2011 saw the launch of an international 

effort among vasculitis experts, including 

rheumatologists, nephrologists, pathologists 

and others, to replace honorific eponyms of 


■ A new artificial neural network helps 

to differentiate subtypes of ANCAassociated 

vasculitis, including 

granulomatosis with polyangiitis (GPA) 2 

■ The effects of rituximab on granulomatous 

and vasculitic manifestations of GPA 

offer hope for patients with refractory 

disease, plus insights into the pathology 

of granulomatous lesions 7 

■ Autoantibodies with transmembrane 

protein targets are found—and 

generated—in GPA granulomas, but are 

undetectable in plasma 9 

diseases with names that highlight diseasespecific 

characteristics. 1 GPA is in fact the test 

case for this initiative; its new name underlines 

the clinical and pathological similarities 

between GPA and MPA with regard to smallcaliber 

vessel involvement, while emphasizing 

the importance of granulomatous 

inflammation as a distinctive feature of GPA 

(Figure 1a). Indeed, since the introduction 

of effective immunosuppressive protocols 

that control vasculitic manifestations of GPA 

(and other AAV), clinicians have increasingly 

faced the challenges posed by granulomatous 

manifestations (for which effective treatments 

have lagged behind). Differentiating 

GPA and MPA, however, is sometimes difficult 

(biopsy proof of GPA is required, and 

established diagnostic criteria are lacking), 

especially when inter disciplinary care cannot 

be provided. Surrogate markers of granulomatous 

inflammation have been proposed to 

dis tinguish GPA, but are, as yet, unvalidated. 

Linder and colleagues 2 stepped into this 

breach in 2011, applying an artificial neural 

net work (ANN) approach to generate and 

validate improved criteria for distinguishing 

GPA and MPA. The ability of ANNs to find 

patterns in complex data sets has previously 

been used to differen tiate GPA and CSS. 3 

In training the ANN, Linder et al. 2 identified 

four potentially rele vant parameters 

—involvement of the nose, sinuses, or ears, 

and presence of pulmonary nodules—to help 

in differen tiating between GPA and MPA. 

Indeed, when these cri teria were applied as 

the only input neurons, the ANN correctly 

differentiated cases of GPA and MPA with an 


accuracy of 94.3%, 2 a substantial improvement 

over conventional classification criteria. 

Importantly, the authors validated the ANN 

in two independent cohorts of patients with 

GPA (n = 46) and MPA (n = 21) from a single 

center. 2 This study, therefore, confirms that 

certain surrogate markers can be used in differential 

diagnosis of GPA, while also indicating 

that ANNs might be useful to distinguish 

AAV subtypes in clinical trials. 

ANN-type approaches to the classification 

of AAV might be enhanced by the inclusion 

of demographic and genetic markers. 

It is now known, for example, that MPA is 

much more common than GPA in Japan, 

whereas GPA is the predominant AAV in 

the UK. 4 Further more, a genetic associ ation 

study in German and British patients with 

AAV found HLA-DPB1*0401 to be a strong 

risk factor for GPA, but not MPA or CSS, 5 

suggest ing that HLA-DPB1*0401 might 

contri bute to the granulomatous aspect of 

GPA. The Euro pean Vasculitis Study Group 

has defined two pheno types of GPA—the 

rare, local ized phenotype that presents with 

granuloma tous tissue inflammation but 

without clinical signs of vasculitis, and the 

more frequent general ized phenotype of 

GPA, which features granulo matous tissue 

inflammation alongside systemic vasculitis. 

Localized disease was thought to be an essentially 

harmless variant of GPA, but recent 

studies have shown that granulomatous 

manifestations can indeed cause significant 

morbidity and even death. As these manifestations 

tend to be more refractory to treatment 

than vasculitic aspects of GPA, the need 

to understand and treat them is pressing. 6,7 

Now, Holle and colleagues 7 have com pared 

the efficacy of the B-cell depleting anti body 

rituximab for the treatment of granulo matous 

and vasculitic manifestations of GPA. 

Their study, in 59 patients with refractory 

GPA, included a high proportion of patients 

with orbi tal masses and pachymeningitis. 7 

Com plete or partial remission was achieved 

for 90% of refractory vasculitic but only 

58% of granulomatous manifestations, and, 

interest ingly, rituximab was more effec tive 

for pulmonary masses (83.4% responded, 

with 16.7% achieving complete remission) 

compared with either orbital masses (44.4% 

responded but none achieved complete 

remission) or pachymeningitis (50.0% and 

8.3%, respectively). The rationale for using 

rituximab in AAV is to eliminate ANCAproducing 

B cells, and is based on a large body 

of evidence indicating a key role for ANCA 

in AAV small-vessel inflammation. Data 

published in 2010 8 added to this rationale by 

a 

b 

showing that ANCAs stimulate neutro phils 

to release B-cell activating factor (BAFF, also 

known as BLyS and TNFSF13B), which might 

perpetu ate ANCA production by increas ing 

the survival of auto reactive B cells. Nevertheless, 

ANCA and B-cell involvement in 

the granuloma tous in flammation of GPA 

remains largely unexplored. 

Although consistent with a possible partial 

role for B cells in granulomatous inflammation, 

the findings of Holle et al. 7 indicate that 

B-cell-independent mechanisms are at the 

heart of granuloma formation. In fact, 

the granulomatous lesions of GPA har bor 

B-cell-rich germinal center-like lymphoid 

structures, and have long been suspected 

to be the very sites where pathogenic 

auto antibody-secreting B cells arise. In a tour 

de force, Thurner and colleagues 9 provided 

in 2011 the first evidence for the existence 

of auto antibody-secreting B cells in GPA 

granulomas. Using laser micro dissection, 

they isolated single B cells from GPA granulomata, 

cloned their immunoglobulin genes, 

reconstituted the corresponding antibodies 

Giant cells 

RHEUMATOLOGY 

Figure 1 | Clinical burden of granulomatous manifestations in GPA. a | Left panel: MRI showing 

retro-orbital ‘granuloma’ (arrowhead) leading to vision loss; middle panel: photograph and CT scan 

showing severe bone and cartilage destruction, with saddle nose, loss of inner nose, and fistula 

between the orbit and cavum nasi (arrowheads); right panel: large septal defect (circled) with 

granulomatous ‘pannus’ (arrowhead). b | Histopathology of GPA. Left panel: sinonasal mucosa 

(adjacent to area of geographic necrosis, not shown) showing giant cells (arrowheads), ELS 

(circled) and eroded bone (B) with palisading fibrocytes (crosses). Right panel: key pathological 

features. B-cell-rich ELS resemble germinal centers, and B cells isolated from them can produce 

autoantibodies. 9 Abbreviations: ELS, ectopic lymphoid structures; GPA, granulomatosis with 

polyangiitis; PMN, polymorphonuclear leukocytes. Permission to use her image was obtained from 

the patient depicted. Photograph and CT scan reproduced from Aries, P. M. & Both, M. N. Engl. 

J. Med. 352, 392 (2005), © Massachusetts Medical Society; histopathology slide reproduced 

from Mueller, A. et al. Rheumatology (Oxford) 47, 1111–1113 (2008), with permission. 

and, finally, tested their binding to human 

proteins. ‘Disappointingly’ none bound 

to proteinase 3 (one of the principle autoantigen 

targets of ANCAs), perhaps owing 

to the small number of antibodies tested. 

Two transmembrane proteins, the lysosomal 

protein TMEM9B and cell-surface 

expressed TM4SF2, were, however, identified 

as antigens for these auto antibodies. 9 

Interestingly, two different anti bodies from 

the same granuloma recognized TMEM9B, 

whereas no circulating antibodies against the 

protein could be detected in the corresponding 

patient plasma. Thus, this study 9 not only 

helps to elucidate the role of the granuloma 

in autoantibody formation (Figure 1b), but 

also makes a strong point that the search for 

new autoantibodies in inflammatory diseases 

should encompass tertiary lymphoid structures 

in inflamed tissues, and not be restricted 

to plasma. Furthermore, the findings clearly 

suggest that ANCA-secreting B cells might 

well be present in granulomatous tissue even 

when they are not detectable in plasma (that 

is, in ANCA-negative patients with GPA). 


* 

* 

B 

B 

PMN 

Epitheloid cells 

ELS 

Fibrocyte rich 

pannus-like tissue 

Destruction of 

bone and cartilage

RHEUMATOLOGY 

Elucidating the role of B cells in granulomatous 

tissue injury would not only underpin 

the rationale for using B-cell depletion 

in granulomatous complications of GPA, 

but also inspire new B-cell directed drugs. 

Ulti mately, however, we will need to understand 

why B-cell-rich germinal center-like 

structures arise within GPA lesions, and how 

B cells are (dys)regulated by the local innate 

immune response. Promisingly, several genes 

involved in innate immunity have recently 

been implicated in GPA. 10 Only with more 

such studies will we begin to get to grips 

with the complex pathophysiology of this 

fascinating disease—and the true meaning 

of its name… 

Department of Rheumatology, University 

Hospital of Southampton NHS Foundation 

Trust, University of Southampton, Southampton 

SO16 6YD, UK (S. D. Gadola). Department of 

Rheumatology, University Hospital of 



in Nature Reviews Rheumatology. Research Highlights, News & Views, Reviews, 



Schleswig-Holstein, Campus Lübeck, D-24576 

Bad Bramstedt, Germany (W. L. Gross). 

Correspondence to: W. L. Gross 

w.gross@klinikumbb.de 



1. Falk, R. J. et al. Granulomatosis with 

polyangiitis (Wegener’s): an alternative name 

for Wegener’s granulomatosis. Arthritis Rheum. 

63, 863–864 (2011). 

2. Linder, R. et al. Differentiation between 

Wegener’s granulomatosis and microscopic 

polyangiitis by an artificial neural network and 

by traditional methods. J. Rheumatol 38, 

1039–1047 (2011). 

3. Schmitt, W. H., Linder, R., Reinhold-Keller, E. 

& Gross, W. L. Improved differentiation between 

Churg-Strauss syndrome and Wegener’s 

granulomatosis by an artificial neural network. 

Arthritis Rheum. 44, 1887–1896 (2001). 

4. Fujimoto, S. et al. Comparison of the 

epidemiology of anti-neutrophil cytoplasmic 

antibody-associated vasculitis between Japan 

and the UK. Rheumatology (Oxford) 50, 

1916–1920 (2011). 

5. Arning, L. et al. Are there specific genetic 

risk factors for the different forms of ANCAassociated 

vasculitis? Ann. Rheum. Dis. 

70, 707–708 (2010). 

6. Holle, J. U. et al. Prospective long-term 

follow-up of patients with localised Wegener’s 

granulomatosis: does it occur as persistent 

disease stage? Ann. Rheum. Dis. 69, 

1934–1939 (2010). 

7. Holle, J. U. et al. Rituximab for refractory 

granulomatosis with polyangiitis (Wegener’s 

granulomatosis): comparison of efficacy 

in granulomatous versus vasculitic 

manifestations. Ann. Rheum. Dis. http:// 

dx.doi.org/10.1136/ard.2011.153601 

8. Holden, N. J. et al. ANCA-stimulated neutrophils 

release BLyS and promote B cell survival: 

a clinically relevant cellular process. Ann. 

Rheum. Dis. 70, 2229–2233 (2010). 

9. Thurner, L. et al. Wegener’s granuloma harbour B 

lymphocytes with specificities against a 

proinflammatory transmembrane protein and 

a tetraspanin. J. Autoimmun. 36, 87–90 (2011). 

10. Laudien, N. et al. Molecular signatures of a 

disturbed nasal barrier function in the primary 

tissue of Wegener’s granulomatosis. Mucosal 

Immunol. 4, 564–573 (2011). 


UROLOGY 

PROSTATE CANCER IN 2011 

Redefining the therapeutic landscape for CRPC 

Carmel Pezaro and Gerhardt Attard 

2011 was a breakthrough year for the treatment of castration-resistant prostate cancer. The encouraging results 

of two large clinical trials were reported, as well as data identifying a number of promising new therapeutic 

targets. Bone-modulating agents continued to show potential for the prevention of skeletal events. 

Pezaro, C. & Attard, G. Nat. Rev. Urol. 9, 63–64 (2012); published online 17 January 2012; doi:10.1038/nrurol.2011.235 

A number of significant breakthroughs 

in the field of advanced prostate cancer 

were reported this year, both clinically and 

in translational and scientific research. 

Recently reported analy ses of the phase III 

studies of abiraterone acetate and MDV3100 

provide irrefutable evidence that the androgen 

receptor (AR) is a critical target in 

castration- resistant prostate cancer (CRPC). 1 

These agents entered clinical development 

5–6 years ago and proceeded to large (>1,000 

patients) phase III trials in docetaxel-treated 

patients. 2 MDV3100 is a novel potent AR 

antagonist, and abiraterone acetate specifically 

inhibits CYP17A1, a key enzyme in the 

testosterone bio synthesis pathway that converts 

adrenal and potentially intratumoral 

steroid precursors into androgens. 

Interim analysis of the abiraterone acetate 

trial revealed that abiraterone acetate 

plus prednisone improved survival by 

3.9 months compared to placebo plus prednisone 

(HR 0.65; P

UROLOGY 


■ Abiraterone acetate can now be 

considered standard of care for patients 

with CRPC who progress on docetaxel 1 

■ Dual blockade of the PI3K–AKT pathway 

and the androgen receptor has emerged 

as an important potential strategy for 

reversing castration resistance 5 

■ Preclinical validation of targeting of 

PARP in ETS-positive cancers introduces 

a potential new biologically rational 

approach for treating advanced prostate 

cancer 7 

■ Denosumab is superior to zoledronic acid 

in delaying skeletal-related events in men 

with bone metastasis 9 

■ Radium 223 chloride improves survival 

in patients with advanced CRPC and 

symptomatic bone metastases 10 

owing to ETS gene rearrangements has 

been directly implicated in tumor invasion 

and metastasis in prostate cancer cell 

lines; therefore, the downregulation of these 

proteins could help explain the antitumor 

activity of therapeutics that disrupt AR signaling 

in nonselected patients. Accordingly, 

it has been suggested that direct targeting 

of ETS proteins could avoid the toxicity 

and AR-related drug resistance of 

hormone therapies. 

In a study published this year, Brenner 

et al. 7 screened for proteins that interact 

with ERG. They found that trans cription 

regulated by both ERG and ETV1 was 

mediated by a protein complex comprising 

PARP1 (poly ADP-ribose polymerase 1) 

and DNAPKcs (DNA-dependent protein 

kinase, catalytic subunit), and that disruption 

of this complex using PARP1 inhibitors 

suppressed growth of ETS-driven cancers. 

Moreover, it has also been hypothesized 

that some sporadic prostate cancers (possibly 

those involving loss of PTEN) contain 

DNA repair defects, so PARP1 inhibition 

could function as an effective therapy either 

directly via synthetic lethality or indirectly 

through inhibition of the PARP1–ETS 

complex. 8 Studies of PARP inhibitors, both 

alone and in combination with AR-targeting 

drugs, are now planned. 

Targeting of bone metastases has long 

been a priority in CRPC, because of both 

its frequent occurrence and associated 

morbidity. The phase III double-blind 

study of denosumab, a humanized monoclonal 

antibody against receptor activator 

of nuclear factor κB ligand (RANKL; 

a stimulator of osteoclastic bone resorption) 

versus zoledronic acid was published 

earlier this year. 9 Although denosumab 

treatment resulted in a 3.6-month advantage 

in the composite end point of time to 

a skeletal-related event (SRE), there was no 

alteration in overall survival or disease progression. 

The clinically important adverse 

event of jaw osteonecrosis was rare, occurring 

in 22 patients in the denosumab group 

and 12 men who received zoledronate. 

These results suggest that denosumab is 

more effective at delaying SREs than the 

current standard. Denosumab also offers 

advantages in terms of its subcutaneous 

administration and a lesser requirement 

for renal monitoring; however, cost may 

limit its widespread use. 

The potential survival benefit of effective 

bone targeting was proven in the recently 

presented phase III ALSYMPCA trial, 

testing the intravenously delivered alphaemitter 

radium 223 chloride, which incorporates 

in place of calcium in replicating 

bone causing double-strand DNA damage 

in adjacent cells. ALSYMPCA compared 

radium 223 chloride with best supportive 

care in men with symptomatic bone-only 

meta stases. 10 The trial was unblinded after 

the preplanned interim analysis met efficacy 

criteria, demonstrating a 2.8-month 

improvement in the primary survival 

end point in the radium 223 chloride group 

(HR 0.695; P = 0.00185). Secondary efficacy 

end points of time to SRE, time to 

PSA progression, and extent and duration 

of alkaline phosphatase response also 

favored the experimental arm. The rate of 

hemato logical toxicity was low, but there 

was an increased rate of grade 1–2 diarrhea 

observed in patients who received 

active treatment. Radium 223 chloride could 

therefore prove to be a highly effective 

treatment with low morbid ity for men with 

bone metastases. 

In summary, significant milestones in 

prostate cancer research in 2011 included 

announcement of the results of two positive 

phase III trials (ALSYMPCA and 

AFFIRM); granting of marketing approval 

for abiraterone acetate by the FDA and the 

EMA; and approval of cabazitaxel, already 

approved by the FDA in 2010, by the EMA. 

Furthermore, increased use of the autologous 

vaccine therapy sipuleucel-T for 

the treatment of predominantly chemotherapy-naive 

patients was reported in the 

USA. Over the next 12 months physicians 

could therefore have at their disposal five 

new agents (abiraterone acetate, MDV3100, 

cabazitaxel, sipuleucel-T and radium 223 

chloride) in addition to docetaxel that 

prolong the life of patients with CRPC, and 

a second bone-modulating agent in addition 

to bisphosphonates (denosumab). 

Additionally, an unprecedented number of 

clinical trials are currently accruing patients 

with prostate cancer to test promising novel 

therapies. The therapeutic landscape of 

CRPC has certainly been redefined over the 

past 2 years. It is now anticipated that significant 

further advances will require biologically 

rational targeting of mol ecularly 

defined subgroups. 

Section of Medicine, The Institute of Cancer 

Research and the Royal Marsden NHS 

Foundation Trust, Downs Road, Sutton, Surrey 

SM2 5PT, UK (C. Pezaro, G. Attard). 

Correspondence to: G. Attard 

gerhardt.attard@icr.ac.uk 


G. Attard declares associations with the following 

companies/organizations: AstraZeneca, The 

Institute of Cancer Research, Ipsen, Janssen-Cilag 

and Sanofi-Aventis. See the article online for full 

details of the relationships. C. Pezaro declares no 

competing interests. 

1. de Bono, J. S. et al. Abiraterone and increased 

survival in metastatic prostate cancer. N. Engl. 

J. Med. 364, 1995–2005 (2011). 

2. Attard, G. & de Bono, J. S. Translating scientific 

advancement into clinical benefit for castrationresistant 

prostate cancer patients. Clin. Cancer 

Res. 17, 3867–3675 (2011). 

3. Scher, H. I. et al. Evaluation of circulating tumor 

cell enumeration as an efficacy response 

biomarker of overall survival in metastatic 

castration-resistant prostate cancer (mCRPC): 

Planned final analysis of COU-AA-301, a 

randomized, double-blind, placebo-controlled, 

phase III study of abiraterone acetate plus lowdose 

prednisone post docetaxel [abstract]. 

J. Clin. Oncol. 29, LBA4517 (2011). 

4. Mulholland, D. J. et al. Cell autonomous role of 

PTEN in regulating castration-resistant prostate 

cancer growth. Cancer Cell 19, 792–804 

(2011). 

5. Carver, B. S. et al. Reciprocal feedback 

regulation of PI3K and androgen receptor 

signaling in PTEN-deficient prostate cancer. 

Cancer Cell 19, 575–586 (2011). 

6. Wang, Y. et al. Differential regulation of PTEN 

expression by androgen receptor in prostate 

and breast cancers. Oncogene 30, 4327–4338 

(2011). 

7. Brenner, J. C. et al. Mechanistic rationale for 

inhibition of poly(ADP-ribose) polymerase in 

ETS gene fusion-positive prostate cancer. 

Cancer Cell 19, 664–678 (2011). 

8. de Bono, J., Sandhu, S. & Attard, G. Beyond 

hormone therapy for prostate cancer with PARP 

inhibitors. Cancer Cell 19, 573–574 (2011). 

9. Fizazi, K. et al. Denosumab versus zoledronic 

acid for treatment of bone metastases in men 

with castration-resistant prostate cancer: 

a randomised, double-blind study. Lancet 377, 

813–822 (2011). 

10. Parker, C. et al. Overall survival benefit of 

radium-223 chloride (Alpharadan) in the 

treatment of patients with symptomatic bone 

metastasis in castration-resistant prostate 

cancer: a phase III randomised trial 

(ALSYMPCA) [abstract LBA1]. Presented at the 

16 th ECCO–36 th ESMO Annual Congress. 


BLADDER CANCER IN 2011 

The dawn of personalized medicine 

Thomas W. Flaig and Dan Theodorescu 

Long awaited data from the clinical investigation of bladder cancer in 

both the neoadjuvant and adjuvant settings were released in 2011, 

setting the stage for the next generation of work in this area. The findings 

of a number of studies provide the first steps towards a personalized 

approach to this disease. 

Flaig, T. W. & Theodorescu, D. Nat. Rev. Urol. 9, 65–66 (2012); published online 20 December 2011; 

doi:10.1038/nrurol.2011.220 

2011 was a year of progress in the field of 

bladder cancer. Efforts to set the context 

for more definitive, practice-changing 

studies of targeted agents in bladder cancer 

were reported. Updated analysis of a large 

European phase III trial of neoadjuvant 

chemo therapy confirmed a significant 

survival advantage, and mutations that 

define potential drivers of disease, as well 

as a gene signature that predicts lymph node 

involvement before cystectomy, are now 

available. Taken together, these advances 

make signifi cant strides in our understanding 

of bladder cancer and begin to pour 

the founda tion for a more personalized 

approach to the assessment and treatment 

of affected patients. 

Currently, no targeted therapies are utilized 

in the routine clinical care of advanced 

bladder cancer, and this is largely due to 

lack of study rather than negative results. 

Two notable studies published in 2011 

addressed this dearth of evidence. The 

importance of angiogenesis in oncogenesis 

is widely accepted and several antiangiogenic 

agents have been approved for cancer 

treatment in recent years. Preclinical evidence 

indicates that the vascular end othelial 

growth factor (VEGF) axis is important in 

urothelial carcinoma, but there has been 

little clinical investigation of vascular inhibition 

in patients with urothelial cancer. 

This year, the Hoosier Oncology Group 

published a single-arm, phase II study of 

a 21-day cisplatin– gemcitabine regimen 

for advanced urothelial carcinoma with 

addition of the VEGF-directed antibody 

bevacizumab, in 43 patients. 1 The overall 

radiographic response rate was 72% (19% 

were complete responses), with a median 

overall survival of 19.1 months. Both of 

these outcomes are encouraging and suggest 

improvement over historical series, in 

which overall survival has ranged from 14 

to 18 months. Pulmonary embolism or deep 

vein thrombosis was observed in 21% of 

the study cohort, prompting a dose reduction 

of gemcitabine midway through the 

trial. The Cancer and Leukemia Group B is 

sponsoring a randomized, phase III study 

of this regimen in patients with advanced 

uro thelial carcinoma (Clinical trials.gov 

identifier: NCT00942331). 

Adding to our insight of targeted therapy, 

a new understanding of the mechanism of 

pulmonary metastasis in bladder cancer was 

described in 2011. Endothelin-1 (ET-1) is a 

vasoconstrictor, expression levels of which 

correlate positively with muscle invasion 

and negatively with bladder cancer- specific 

survival. In new preclinical findings, ET-1 

and its receptor were determined to be 

neces sary for lung metastasis in bladder 

cancer, and this process was shown to be 

dependent on macrophage activity in the 

lung. 2 Importantly, pharmacologic inhibition 

of the ET-1 axis, using orally bioavailable 

ET-1 receptor inhibitors, prevented the 

development of lung metastases, but had 

little effect on established primary or metastatic 

tumors. Attempting to translate these 

findings into a clinical context suggests that 

the use of ET-1 receptor inhibitors will be 

most efficacious in the adjuvant setting, not 

in the metastatic setting. This information 

may guide the future development of ET-1 

inhibitors for bladder cancer, given their 

availability and tolerability for chronic use. 

An important update to the large 

European phase III neoadjuvant chemotherapy 

trial was reported in 2011. 3 This trial 

included patients with T2 grade 3, T3 or T4a 

bladder cancer (N0 M0) planning to undergo 

radical cystectomy or definitive radiation 

therapy. A total of 976 patients were randomized 

to either three cycles of a 21-day cisplatin, 

methotrexate and vinblastine (CMV) 

chemotherapy regimen or no chemotherapy 

before undergoing cyst ectomy or radiation 

therapy. The initial reports of this study in 

1999 revealed a trend toward chemotherapy 

benefit that did not reach significance. In the 

© Orlando Florin Rosu | Dreamstime.com 

UROLOGY 

updated report, there was a 16% reduction in 

the risk of death and an absolute increase in 

the 10-year survival (from 30% to 36%) with 

CMV chemotherapy. Of note, the reduction 

in the risk of death was 26% in patients 

treated with cyst ectomy, which is compar able 

to that reported in the neo adjuvant findings 

with metho trexate, vinblastine, doxorubicin, 

and cisplatin (MVAC) chemotherapy 

reported by SWOG. 4 Importantly, there is 

now evidence of a survival advantage with 

the use of neoadjuvant chemotherapy in two 

randomized, phase III studies, so a discussion 

of neo adjuvant chemotherapy should 

take place in all fit patients with muscle- 

invasive disease preparing for definitive local 

bladder cancer therapy. 

Despite these positive findings, which are 

based on pathological risk stratification, it 

is clear that the majority of patients treated 

with neoadjuvant chemotherapy do not 

benefit. A robust prognostic test is needed 

that would facilitate the use of chemotherapy 

in those at highest risk of recurrence, with 

a predictive test to select the therapy most 

likely to elicit a response in each patient. 

We did see some progress in the search for 

better prognostic markers for bladder cancer 

in 2011. In one new study, gene expression 

was assessed in three separate cystectomy 

cohorts and evaluated in the context of 

pathologic lymph node status at the time 

of surgery. 5 Two cohorts (including 90 and 

66 patients) were used as training sets and a 

20-gene signature was developed, which was 

validated in a larger group (n = 185). Patients 

in the valida tion cohort were prospectively 

collected in an earlier clinical trial and analyzed 

retrospectively. The 20-gene expression 

model yielded an RR for the discovery 

of lymph node metastases of 1.74 in the 

desig nated ‘high-risk’ group compared to 

an RR of 0.70 in ‘low-risk’ patients, and was 

independent of stage and lymphovascular 


UROLOGY 


■ Encouraging results have been obtained 

from studies of targeted therapies in 

bladder cancer, 1 laying the groundwork for 

future investigation in this area 

■ The reporting of a second randomized 

phase III trial of neoadjuvant 

chemotherapy 3 confirms a survival 

advantage for patients with muscleinvasive 

bladder cancer 

■ A 20-gene expression model has been 

developed 5 that can identify patients, 

before cystectomy, at high risk of lymph 

node involvement 

■ Evidence suggests a number of chromatin 

remodeling genes are involved in bladder 

cancer, 6 representing a novel area for 

future investigation 

■ The immunohistochemical assessment of 

p53 is not a useful marker of prognosis or 

predictive of response to chemotherapy 9 

invasion. Conceivably, with further validation, 

patients at high risk of node-positive 

disease could be identified using this algorithm 

and then strongly encouraged to 

undergo neoadjuvant chemotherapy before 

definitive treatment. 

Whole-exome sequencing of paired 

tumoral and peripheral blood samples 

was recently performed in a small set of 

patients with bladder cancer, in an attempt 

to identify prognostic biomarkers. 6 The 

initial findings from this cohort were then 

tested in a larger cohort of 88 patients. 

Several previously defined mutations were 

observed (in TP53, RB1 and HRAS), as well 

as a number of novel mutations. Of these, 

UTX was the most commonly mutated 

gene, identified in 21% of tested individuals, 

with 17 nonsense, 5 missense and 1 synonymous 

mutation noted when combining the 

discovery and validation screens. Of particular 

note, eight of the newly identified 

mutated genes were related to chromatin 

remodeling, suggesting a potential area for 

bladder cancer investigation. Interestingly, 

mutations in chromatin remodeling genes 

have been commonly found in several other 

cancer types, suggesting a fundamental 

contribution to carcinogenesis. 

Results of retrospective studies have suggested 

that p53 is both a marker of prognosis 

7 and potentially predictive of response 

to cytotoxic chemotherapy. 8 However, the 

results of a much anticipated phase III trial 

testing p53 as a biomarker in patients after 

radical cystectomy were somewhat disappointing. 

9 Notably, these patients had early 

stage disease (pT1–2 N0 M0), and based 

on current pathologic risk stratification 

they would frequently not receive adjuvant 

chemo therapy. Patients whose tumors were 

negative for p53 overexpression—with

Aging Study (MMAS) and the multinational 

Men’s Attitudes to Life Events and 

Sexuality (MALES), revealed that 21% and 

25% of men reported improvement, over 

7 and 3 years of follow-up, respectively. 2 

Worsening of ED was reported by 51% and 

28% of men in MMAS and MALES, respectively. 

As might be expected, the proportion 

of men reporting progression increased 

with age, and men younger than 50 years 

were more likely to experience improvement 

than worsening. The age-specific rates 

of progression were higher in MMAS than 

in MALES, which might be explained by the 

fact that the MMAS population is older or 

that there was a longer period of follow-up 

in MMAS than MALES. 

Only a small proportion of men (14% 

in MMAS and 28% in MALES) reported 

use of phospho diesterase type 5 (PDE5) 

inhibitors, which is not uncommon in 

population- based studies. Furthermore, 

most patients were recruited before the 

commercialization of PDE5 inhibitors. 

Although this study reported several pertinent 

findings, there are problems associated 

with combining data from several longitudinal 

studies, including the difference in 

follow- up duration between studies. 

Moreover, self-reported outcomes might 

not represent formal diagnosis of a condition, 

and the lack of access to PDE5 inhibitors 

or other erectogenic agents may further 

restrict the generalization of this study. 

A novel treatment for men with vasculogenic 

ED was reported in 2011: extracorporeal 

shock wave therapy (ESWT). In 

contrast to high-intensity ESWT, which is 

commonly used to treat urolithiasis and 

orthopedic conditions, a low-intensity 

protocol (LI-ESWT) has previously been 

shown to improve the hemodynamics of 

many organs via an improvement in vascular 

supply and endothelial function. 

Neovascularization is mediated by the nonenzymatic 

production of physiologic levels 

of nitric oxide, activa tion of intracellular 

signaling pathways, and increased expression 

of vascular endothelial growth factor 

and its receptor. 

This year, Gruenwald et al. 3 reported 

that penile LI-ESWT (two treatment sessions 

per week for 3 weeks in 29 patients) 

can improve erectile function and penile 

hemodynamics. The mean IIEF-ED 

scores increased from 8.8 ± 1 at baseline to 

12.3 ± 1 at 1-month follow-up (P = 0.035). 

At 2 months, while patients were on active 

PDE5 inhibitor treatment, the IIEF-ED 

further increased to 18.8 ± 1 (P

UROLOGY 

either placebo, vardenafil (10 mg), sildenafil 

(50 mg) or tadalafil (20 mg), after 3 days 

of sexual abstinence. Despite the absence 

of any sexual stimulation, 10%, 41%, 26% 

and 55% of men in the placebo, sildenafil, 

tadalafil and vardenafil groups, respectively, 

were able to achieve ≥60% base or 

tip rigidities (P

ather information on the 95 th percentile of 

semen analysis data. As such, they inform 

the reader that 95% of men who achieve 

pregnancy within 12 months of trying will 

have sperm concentrations of >15 million 

cells/ml, >40% of observed sperm demonstrating 

good movement, and >4% of sperm 

with normal morphology. 

Unfortunately, these criteria do not 

predict the likelihood of achieving a pregnancy 

in the following 12 months, which 

is typically when urologists first see these 

patients in consultation. Furthermore, the 

reference range must be viewed as a continuum, 

given that many patients at the low 

end of the range might still achieve pregnancy, 

and men at the high end might not. 

The nondefinitive nature of these guidelines 

confirms the need for further sophisticated 

testing—such as DNA fragmentation analysis, 

oxidative stress analysis and sperm 

evaluation for genomic, proteomic and 

metabolic factors—in certain cases of 

male factor or unexplained infertility. For 

example, a patient whose semen parameters 

fall within the new reference ranges but 

has not achieved pregnancy might benefit 

from DNA fragmentation testing to identify 

subtle sperm abnormalities. Esteves et al. 2 

have analyzed the new reference values 

and highlight further issues that may face 

the urologist, including whether the referral 

of male partners will decrease, whether 

we were previously overtreating our male 

patients and how to better interpret these 

reference values by focusing on the 50 th 

percentile of data. 

Over the past decade, progress in the 

field of assisted reproduction has led to a 

change in the management of severe male 

factor infertility not amenable to medical 

or surgical correction. Currently, intracytoplasmic 

sperm injection (ICSI) is 

the treatment of choice for patients who 

suffer from either severe oligospermia 

or non obstructive azoospermia (NOA). 

Historically, any motile sperm present in the 

ejaculate would be preferentially utilized for 

ICSI. Alternatively, if no sperm were found 

in the ejaculate, sperm surgically extracted 

from the testis were used instead. When 

very low numbers of sperm were present 

in the ejaculate and initial ICSI results with 

motile ejaculated sperm were poor, then 

testis sperm was considered. 

Evidence against this ejaculate-first 

approach was recently reported by Hauser 

et al., 3 who found that fertilization rates in 

patients with relative or virtual azoospermia 

were higher when fresh or frozen-thawed 

testicular sperm cells were used than when 

ejaculated sperm cells were used. This 

finding is particularly interesting considering 

that although more motile sperm 

cells were found in the ejaculated specimens 

than in the testicular samples, the 

quality of embryos from testicular sperm 

(fresh and frozen) was significantly higher 

than of those from ejaculated sperm. This 

observa tion led the authors to conclude that 

it is the source of sperm cells, and not their 

motility, that plays a crucial role in fertility 

outcome. This pilot study suggests a possible 

role for testicular sperm extraction 

(TESE) coupled with ICSI in patients with 

severe oligo asthenospermia or relative or 

virtual azoo spermia. 

If testicular sperm leads to better fertility 

outcomes, does it matter if fresh or 

frozen-thawed testicular spermatozoa are 

retrieved? According to Hauser et al., 3 the 

answer is yes. While frozen-thawed spermatozoa 

may be more conveniently obtained, 

the researchers found that for patients with 

virtual or relative azoospermia, fresh testis 

sperm yielded better implantation rates 

than frozen testicular sperm. 

Although these results support the use 

of fresh testicular sperm for patients with 

relative or virtual azoospermia, there is 

still no consensus on the best approach for 

retrieving testis sperm from men with pure 

NOA. This year, the value of diagnostic testis 

biopsy in the era of ICSI was addressed by 

Kalsi et al., 4 who provide evidence that 

microsurgical TESE (m-TESE)— introduced 

by Schlegel and Li 5 in 1998—is the optimum 

sperm retrieval method in patients with 

NOA, preferential to fine-needle aspira tion 

and traditional TESE. 

Researchers were able to successfully 

retrieve spermatozoa from 50 of 100 men 

with NOA who underwent m-TESE at their 

center, which includes a success rate of 57% 

in men with previously failed attempts at 

sperm retrieval. The only significant positive 

predictor of a successful retrieval was 

a previous histological diagnosis of hypospermatogenesis, 

and therefore the authors 

recommend against the common practice 

of performing isolated diagnostic testicular 

biopsies on men with NOA, and suggest 

instead that biopsy should always be combined 

with a TESE procedure. Therefore, 

the take home message for any urologist 

treating a patient with NOA is to either 

proceed with a combined diagnostic testis 

biopsy and send tissue to an andrology laboratory 

for processing and cryo preservation, 

or to refer the patient to a reproductive 


UROLOGY 

■ The updated 5 th edition of the WHO 

semen guidelines includes significant 

changes from prior versions and is the 

first edition to include evidence-based 

data 1 

■ In certain cases, testicular sperm may 

be used for intracytoplasmic sperm 

injection, in preference to ejaculated 

sperm, for patients with relative or virtual 

azoospermia 3 

■ Diagnostic testis biopsy alone (without 

tissue processing) has limited value 

in the management of nonobstructive 

azoospermia 4 

■ The underlying cause of hematospermia 

can be evaluated using transrectal 

ultrasonography 6 

■ Finasteride is a feasible treatment 

option for men with recurrent idiopathic 

hematospermia 7 

urologist who has this capability. Our 

current approach is to begin with a standard 

TESE and if no sperm are observed to 

proceed with an immediate m-TESE. 

Abnormal findings in ejaculate are not 

always related to male factor infertility. In 

fact, one of the most frequently encountered 

problems in general urology is hematospermia, 

which can be a cause of great 

concern and anxiety for affected men. Until 

recently, hematospermia was assumed to 

be idiopathic and patients were reassured 

that their condition was benign. A recent 

study by Zhao et al., 6 however, may alter the 

urologist’s approach to hematospermia. In 

their study, researchers performed transrectal 

ultrasonography on 270 men with 

hematospermia, and found abnormalities 

in 95% of the cohort. These abnormalities 

were universally benign in patients under 

40 years of age, including prostatic calcifications, 

ejaculatory duct calculi, and benign 

prostatic hyperplasia. Patients over the age 

of 40 years, however, were significantly 

more likely to have a malignant disease; 8 

Courtesy of A. Kilchevsky, Yale–New Haven Hospital, USA 


UROLOGY 

of 126 (6.3%) men over 40 years old were 

found to have prostate, seminal vesicle, or 

bladder cancer. So, although reassurance 

may be appropriate in a younger population, 

hematospermia in men over 40 years 

of age must be evaluated more closely. 

A small randomized study by Badawy 

et al., 7 published this year, evaluated the 

role of finasteride in the treatment of recurrent 

idiopathic hematospermia. This study 

reports the response of 24 patients to treatment 

with finasteride at 5 mg daily for 

3 months. Men who received finasteride 

reported a statistically significant improvement 

in hematospermia compared to those 

in the placebo group (66% versus 25%; 

P = 0.05). Although this is a small study, it 

gives the general urologist an off-label option 

for the treatment of recurrent hemato spermia 

after organic causes (such as infection 

and malignancy) have been ruled out. 

In summary, there have been several new 

developments in the fields of male factor 

infertility and andrology over the last year 

that are of great interest to the general urologist. 

The new WHO guidelines for semen 

quality provide updated reference ranges 

rooted in evidence-based data. New techniques 

for surgical sperm extraction have 

both clarified current approaches and provided 

novel treatment options for NOA and 

relative azoospermia. Finally, new information 

regarding the evaluation and treatment 

of hematospermia will help us better 

identify causality, reassure our patients, and 

provide treatment with better outcomes. 

Department of Urology, Yale–New Haven 

Hospital, Yale Physicians Building, 800 Howard 

Avenue, 3 rd Floor, New Haven, CT 06519, USA 

(A. Kilchevsky). Division of Urology, University 

of Connecticut Health Sciences Center, 263 

Farmington Avenue, Farmington, CT 06030, 

USA (S. Honig). 

Correspondence to: S. Honig 

shonig@srhs.org 



1. Cooper, T. G. et al. World Health Organization 

reference values for human semen 

characteristics. Hum. Reprod. Update 16, 

231–235 (2010). 

2. Esteves, S. C. et al. Critical appraisal of World 

Health Organization’s new reference values for 

human semen characteristics and effect on 

diagnosis and treatment of subfertile men. 

Urology http://dx.doi.org/10.1016/ 

j.urology.2011.08.003. 

3. Hauser, R. et al. Virtual azoospermia and 

cryptozoospermia—fresh/frozen testicular or 

ejaculate sperm for better IVF outcome? 

J. Androl. 32, 484–490 (2011). 

4. Kalsi, J., Thum, M. Y., Muneer, A., Abdullah, H. 

& Minhas, S. In the era of micro-dissection 

sperm retrieval (m-TESE) is an isolated 

testicular biopsy necessary in the management 

of men with non-obstructive azoospermia? BJU 

Int. http://dx.doi.org/10.1111/ 

j.1464-410X.2011.10399.x. 

5. Schlegel, P. N. & Li, P. S. Microdissection TESE: 

sperm retrieval in non-obstructive 

azoospermia. Hum. Reprod. Update 4, 439 

(1998). 

KIDNEY CANCER IN 2011 

Objectifying risk for localized renal 

masses 

Marc C. Smaldone and Robert G. Uzzo 

Contemporary treatment guidelines for the localized renal mass are 

largely driven by expert opinion and retrospective observational data. 

Three articles published in 2011 add important information to the 

existing body of literature, enabling improved objectification of risk and 

individualization of clinical tradeoff decisions for patients presenting with 

localized renal tumors. 

Smaldone, M. C. & Uzzo, R. G. Nat. Rev. Urol. 9, 70–72 (2012); published online 13 December 2011; 

doi:10.1038/nrurol.2011.195 

Increased utilization of abdominal imaging 

has led to a significant rise in the incidental 

detection of clinically localized 

renal tumors. Although the gold standard 

treatment for clinically localized small renal 

masses remains surgical excision, contemporary 

practice patterns have evolved in 

an effort to match treatment strategy to 

tumor characteristics, as well as minimize 

the adverse effects associated with chronic 

kidney disease (CKD). 1 The armamentarium 

of management options has expanded 

to include open and minimally-invasive 

radical nephrectomy, nephron-sparing 

surgical techniques, tumor ablation, and 

active surveillance with curative intent. In 

2009, the American Urological Association 

Guidelines committee issued the following 

recommendation: “surgical excision 

by partial nephrectomy is the reference 

standard for the management of the clinical 

T1 renal mass, whether for imperative 

or elective indications, given the importance 

of preservation of renal parenchyma 

and avoidance of CKD.” 2 However, when 

evaluating these guidelines it is important 

to bear in mind that the evidence quality 

of the contemporary body of literature 

is poor, and is limited primarily to retrospective 

observational studies. As a result, 

treatment decisions are driven primarily by 

expert opinion and surgeon experience, and 

a number of important questions regarding 

the safety and oncologic efficacy of current 

6. Zhao, H. et al. The value of transrectal 

ultrasound in the diagnosis of hematospermia 

in a large cohort of patients. J. Androl. http:// 

dx.doi.org/10.2164/jandrol.111.013318. 

7. Badawy, A. A., Abdelhafez, A. A. & 

Abuzeid, A. M. Finasteride for treatment of 

refractory hemospermia: prospective placebocontrolled 

study. Int. Urol. Nephrol. http:// 

dx.doi.org/10.1007/s11255-011-0057-0. 

management strategies remain unanswered. 

Three studies published in 2011 provide 

evidence that will improve the communication 

of risk and enable tradeoff decisions 

when counseling patients diagnosed with 

localized renal tumors. 

Until recently, level 1 evidence comparing 

the oncologic efficacy of radical and 

partial nephrectomy was lacking. In 2011, 

Van Poppel et al. 3 reported the results of a 

European Organization for Research and 

Treatment of Cancer (EORTC) prospective, 

noninferiority, multicenter, phase III trial 

assessing oncologic outcomes in patients 

with a normal contralateral kidney randomized 

to either radical nephrectomy (n = 273) 

or nephron- sparing surgery (n = 268) for 

solitary localized renal tumors ≤5cm in 

size. 3 Oncologic efficacy was found to be 

equivalent between groups, with 10-year 

progression rates of 4.1% (95% CI 1.7–6.5%) 

and 3.3% (95% CI 1.2–5.4%) for partial and 

radical neph rectomy, respectively (P = 0.48). 

Furthermore, only 12 renal-cancer-related 

deaths were noted in the study, with a 

median follow-up of 9.3 years, suggesting 

that the risk of cancer- specific death in 

patients surgically treated for stage 1 tumors 

is extremely low. However, in the intentionto-treat 

analysis, the authors reported a 

significant 10-year overall survival benefit 

for patients undergoing radical surgery 

compared to partial nephrectomy (81.1% 

versus 75.7%; HR 1.50 [95% CI 1.03–2.16]; 


P = 0.03). When the analysis was limited to 

patients with histologically confirmed renal 

cell carcinoma, these differences in overall 

survival were less pronounced. 

The findings of this study must be placed 

in context of its limitations. Designed to 

recruit 1,300 patients, the trial was closed 

early due to poor accrual, and did not 

achieve the target sample size chosen to 

identify a 3% difference in 5-year survival. 

In addition, there were differences 

in baseline comorbidities and considerable 

crossover between treatment arms (5.6% 

of patients randomized to radical nephrectomy 

underwent partial neph rectomy, 

and 14.6% of patients randomized to partial 

nephrectomy underwent radical nephrectomy), 

which may have influenced the 

reported survival outcomes. Despite these 

limitations, the findings raise important 

questions regarding the relative contributions 

of preserved renal function and competing 

risks from pre-existing comorbidities 

to overall survival following surgical resection 

for localized renal tumors. Although 

these results are thought-provoking, further 

study is necessary to determine which 

patients stand to benefit the most from 

nephron-sparing surgery. 

The benefit of renal function preservation 

in nephron-sparing surgery must 

be weighed against the increased risk of 

postoperative complications compared 

with radical nephrectomy. 2 However, a 

lack of standardized reporting methods 

has resulted in a body of literature with 

limited generalizability that is challenging 

to interpret. In 2011, investigators at 

Fox Chase Cancer Center attempted to 

address these issues by rigorously evaluating 

the complica tions associated with 

partial neph rectomy in their institutional 

database 4 using the Clavien-Dindo 

classifica tion system (CCS). 5 Aiming to 

provide a benchmark for comparative 

studies between institutions, patients were 

stratified using the nephrometry scoring 

system 6 to investigate the relationship 

between tumor complexity (low complexity 

score 4–6; intermediate complexity score 

7–9; high complexity score 10–12) and risk 

of postoperative complications. The study 

cohort consisted of 390 patients with available 

imaging data for review, who underwent 

partial neph rectomy between 2007 

and 2010; 109 (28%), 217 (55.6%), and 

64 (16.4%) patients underwent nephron- 

sparing surgery for low, intermediate, and 

high complexity lesions, respectively. The 

overall proportion of patients incurring 

minor (CCS I–II) and major (CCS III–V) 

complications were 26.7% and 11.5%, 

respectively. No significant differences were 

observed in minor complications between 

complexity groups, but patients with highly 

complex lesions were more likely to develop 

a major complication requiring secondary 

intervention than intermediate and low 

complexity tumors (22% versus 11% versus 

6%; P = 0.001). Controlling for demographic 

and clinical characteristics, patients with 

highly complex renal tumors were 5.4 times 

(95% CI 1.2–24.2) more likely to sustain a 

major complication compared to those with 

low complexity lesions. Although this study 

was limited by its retrospective methodology 

and lack of external validation, these 

findings highlight two important points: the 

rigorous reporting of complications using 

standardized reporting methodology is 

essential for comparing outcomes between 

institutions, and the benefit of nephron 

preserva tion in highly complex tumors 

comes with the attendant risk (>20%) of a 

major post operative complication. 

Recent evidence suggests that a substantial 

proportion of the rapidly rising 

number of incidentally diagnosed small 

renal masses represents indolent disease 


■ In a recent phase III randomized trial, 3 

partial nephrectomy demonstrated 

equivalent cancer-specific survival to 

radical surgery for tumors ≤5 cm, but did 

not demonstrate the expected overall 

survival benefit 

■ The benefit of nephron preservation 

in highly complex tumors comes with 

the attendant risk (>20%) of a major 

postoperative complication 4 

■ A large proportion of small renal masses 

under observation grow slowly, and 

the short-term risks of progression or 

metastasis under active surveillance are 

low 9 

UROLOGY 

that may not require treatment. 7 As a 

result, much attention has been directed 

towards describing the natural history of 

untreated renal tumors in an effort to identify 

which lesions are safe to observe and 

which require early definitive intervention. 8 

In 2011, Jewett et al. 9 reported the results 

of a multicenter prospective phase II trial 

investigating the growth kinetics and progression 

rates of 209 incidentally diagnosed 

cT1a lesions under observation in 

patients deemed unfit for surgery owing 

to advanced age, comorbidity, or refusal 

of other treatment. 9 In this cohort of 178 

patients (mean age 73 years, mean tumor 

size 2.3 cm), the authors defined tumor progression 

as growth to ≥4 cm, tumor volume 

doubling time ≤12 months, or progression 

to metastatic disease. Notably, 99 patients 

(56%) underwent renal biopsy and 127 

patients (151 masses) were followed up for 

>12 months (mean 28 months). Important 

study findings include an average growth 

rate of 0.13 cm per year, documented progression 

(as defined above) in 27 patients 

(15%), and only two patients (1.1%) developing 

evidence of metastatic disease. 

Furthermore, there was no difference in 

growth rate between biopsy-proven malignant 

and benign disease (0.14 cm per year 

versus 0.17 cm per year; P = 0.8), and 36% of 

biopsy-proven renal cell carcinomas showed 

either no evidence of growth or a decrease 

in size. Although limited by lack of central 

pathology review, elevated nondiagnostic 

biopsy rate (33%), and short duration of 

follow-up, this study should be commended 

for its rigorous eligibility criteria, use of protocol 

renal mass biopsy, and strict definition 

of tumor progression. These findings add 

significantly to the growing body of literature 

documenting that a large proportion of 

small renal masses under observation grow 

slowly, and that short-term risks of progression 

or metastasis under active surveillance 

are low. 8,10 

In the absence of level 1 evidence, physicians 

are increasingly challenged to manage 

risk on a patient by patient basis. Although 

the list of unanswered questions remains 

long, the studies described above each 

provide evidence to improve risk communication 

and enable tradeoff decisions 

when counseling patients diagnosed with 

localized renal tumors. Until the ability to 

match treatment to tumor biology has been 

achieved, urologists must continue to vigilantly 

evaluate and challenge contemporary 

management strategies, objectify tradeoff 

risks, and individualize treatment strategies. 


© London_england | Dreamstime.com

UROLOGY 

Division of Urologic Oncology, Department of 

Surgery, Fox Chase Cancer Center, 333 

Cottman Avenue, Philadelphia, PA 19111, USA 

(M. C. Smaldone, R. G. Uzzo). 

Correspondence to: R. G. Uzzo 

r_uzzo@fccc.edu 



1. Go, A. S., Chertow, G. M., Fan, D., 

McCulloch, C. E. & Hsu, C. Y. Chronic kidney 

disease and the risks of death, cardiovascular 

events, and hospitalization. N. Engl. J. Med. 

351, 1296–1305 (2004). 

2. Campbell, S. C. et al. Guideline for 

management of the clinical T1 renal mass. 

J. Urol. 182, 1271–1279 (2009). 



in Nature Reviews Urology. Research Highlights, News & Views, Reviews, 



3. Van Poppel, H. et al. A prospective, randomised 

EORTC intergroup phase 3 study comparing the 

oncologic outcome of elective nephron-sparing 

surgery and radical nephrectomy for low-stage 

renal cell carcinoma. Eur. Urol. 59, 543–552 

(2011). 

4. Simhan, J. et al. Objective measures of renal 

mass anatomic complexity predict rates of 

major complications following partial 

nephrectomy. Eur. Urol. 60, 724–730 (2011). 

5. Dindo, D., Demartines, N. & Clavien, P. A. 

Classification of surgical complications: a new 

proposal with evaluation in a cohort of 6336 

patients and results of a survey. Ann. Surg. 

240, 205–213 (2004). 

6. Kutikov, A. & Uzzo, R. G. The R.E.N.A.L. 

nephrometry score: a comprehensive 

standardized system for quantitating renal 

tumor size, location and depth. J. Urol. 182, 

844–853 (2009). 

7. Hollingsworth, J. M., Miller, D. C., Daignault, S. & 

Hollenbeck, B. K. Rising incidence of small renal 

masses: a need to reassess treatment effect. 

J. Natl Cancer Inst. 98, 1331–1334 (2006). 

8. Chawla, S. N. et al. The natural history of 

observed enhancing renal masses: metaanalysis 

and review of the world literature. 

J. Urol. 175, 425–431 (2006). 

9. Jewett, M. A. et al. Active surveillance of small 

renal masses: progression patterns of early 

stage kidney cancer. Eur. Urol. 60, 39–44 (2011). 

10. Smaldone, M. C. et al. Small renal masses 

progressing to metastases under active 

surveillance: A systematic review and pooled 

analysis. Cancer http://dx.doi.org/10.1002/ 

cncr.26369.

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