2004 Summer Meeting - Amsterdam - The Pathological Society of ...

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Infertile Males – Who Should Be Screened For Cystic Fibrosis
Mutations
EV Mocanu 1 , R Shattock 2 , C Martin 2 , D Barton 3 , M Rogers
3 , O Sheils 2 , JJ O'Leary 2 , RF Harrison 4
1 HARI Unit Rotunda Hospital and Departments of Histopathology, Trinity
College Dublin and Coombe Women's Hospital, Dublin, Ireland, 2
Departments of Histopathology, Trinity College Dublin and Coombe
Women's Hospital, Dublin, Ireland, 3 National Centre for Medical
Genetics, Our Lady's Hospital for Sick Children, Dublin, Ireland, 4 HARI
Unit Rotunda hospital and Royal College of Surgeons in Ireland, Dublin,
Ireland
It is not clear from published literature if subfertile males have a higher carrier
rate of CFTR gene mutations compared with their fertile counterparts. Up to
recently, men with severe oligozoospermia or azoospermia were infertile.
Assisted Reproductive Technology (ART) in the form of IntraCytoplasmic
Sperm Injection (ICSI) has made it possible for these men to become fathers.
Blood DNA samples from 116 fertile men and 586 infertile males with different
degrees of sperm count abnormalities (abnormal karyotype carriers, CBAVD
and Y deleted excluded) requiring ICSI were screened for 31 CF mutations.
The screen involved a Polymerase Chain Reaction Oligonucleotide Ligation
Assay (PCR OLA) with automated gel electrophoresis and computerised
mutation recognition. The incidence of CFTR gene mutations was significantly
higher in the infertile group compared with the fertile population (p=0.005)
mainly due to a high incidence of mutations in the azoospermic group
(p=0.002). All patients were heterozygous for the mutations identified.
This study clearly demonstrates the need for CFTR gene mutations screening in
azoospermic men with no other genetic or obstructive causes for their infertility
and suggests fundamental changes in the provision of care for infertile couples.
142
Overexpression of LAT1 in Human Prostate Cancer
Y Terado , A Sakamoto
Department of Pathology, Kyorin University School of Medicine, Tokyo,
Japan
We investigated the expression of LAT1 L-type amino acid transporter 1 in
prostate cancer by immunohistochemical study. The LAT1 is a Na+independent
neutral amino acid transporter subserving the amino acid transport
system L. We examined 115 needle biopsy specimens of human prostate
cancer. Diffuse and strong positivity for LAT1 was identified in carcinoma
component only. However, partial and weak positivity for LAT1 was found
even in benign prostate glands. Overexpression of LAT1 was detected in 25
21.7% of 115 specimens. Overexpression of LAT1 was observed in 2 4.1%
of 49 Gleason score 2-6 cases, 3 37.5% of 8 Gleason score 7 cases, and 20
34.5% of 58 Gleason score 7-10 cases. There was no difference in
overexpression of LAT1 between Gleason score 7 and Gleason score 8-10
cases. There was significant difference in overexpression of LAT1 between
Gleason score 2-6 and Gleason score 7-10 cases P0.0001. In conclusion,
overexpression of LAT1 is associated with tumor grade of human prostate
cancer. Overexpression of LAT1 might be closely related to the prognosis of
prostate cancer patients.
143
Evidence of expression of a prorenin receptor in renal cell
carcinoma
L.Y. Christie , V. Goojula , M. Aitchison , S. Fleming
1 University of Dundee, Dundee, United Kingdom, 2 Gartnavel general
Hospital, Glasgow, United Kingdom
Most of the components of the renin angiotensin system are present in renal cell
carcinoma (RCC), however renin is secreted in its inactive prorenin form. The
recent discovery of a prorenin receptor capable of non-enzymatic activation of
prorenin provides a potential mechanism for renin activation in RCC. Nguyen
showed prorenin binding to mesangial cells had a hypertrophic effect and
increased the expression of plasminogen activator inhibitor 1. This same group
recently cloned a human prorenin receptor. The cloned sequence appears to
encode a single transmembrane domain protein with no known homology.
Transfected cells exhibit prorenin and renin binding with consequent activation
of the prorenin without cleavage. The aim of the current project was to address
the question is the recently identified activating receptor for prorenin expressed
in human renal cell carcinoma? Samples of snap frozen tissue from cases of
RCC (n=9) were obtained and mRNA extracted. A reverse transcriptase PCR
reaction using primer pair 5’-GGGGGGTGAACTGAGAACA-3’ AND 5’-
GCATTCTCCAAAGGGTACGA-3’ was performed. In 5/9 cases a single band
of the predicted size was obtained. The PCR product was sequenced and found
to be identical to the published sequence for the prorenin receptor. This
provides preliminary evidence that the putative prorenin receptor is expressed
in cases of RCC providing a potential mechanism for intratumoural activation
of the RAS
144
Human ACE Gene Polymorphisms May Be Associated With
Progression In Renal Cell Carcinoma
L A Jamieson 1 , S Fleming 2
1 NInewells Hospital and Medical School, Dundee, United Kingdom, 2
University Of Dundee, Dundee, United Kingdom
A role for the activity of the renin - angiotensin pathway in the progression of
renal cell carcinoma (RCC) is suggested by two observations. First, in a
xenograft model, pharmacological inhibition of angiotensin converting enzyme
(ACE) with subsequent reduction in angiotensin 2 (ANG2) inhibits the growth
of RCC. Further clinical evidence comes from follow up data of hypertensive
patients who developed malignancy. Those treated with ACE inhibitors showed
lower tumour mortality than those who did not receive an ACE inhibitor. There
is a 287bp insertion/deletion (I/D) polymorphism in intron 16 of the human
ACE gene. This has been associated with variance in plasma and tissue
concentrations of ACE, the highest concentrations being in the DD genotype.
Our hypothesis is that patients who are ACE DD homozygotes and who
produce higher levels of ACE should show greater tumour mortality. Fortyeight
archive cases of RCC from 1998 and 1999 in Tayside were selected to
enable follow up data to be obtained. DNA was extracted from formalin fixed,
paraffin embedded sections of normal kidney. The ACE genotype for each case
was established using published primers and PCR. Flanking oligonucleotide
pairs used to characterize the I/D polymorphism anneal outside the 287bp
insertion within intron 16 of the ACE gene. Owing to the preferential
amplification of the D allele, mistyping of I/D heterozygotes as DD
homozygotes is possible; therefore insertion specific primer pairs were used to
verify each DD genotype. Analysis of the 48 cases showed 7 to be ACE II, 10
as ACE DD and 31 were ACE I/D. This distribution itself is not significantly
different from controls, but when staging data is analysed 60% of tumours
which are DD had progressed to greater than stage pT3 compared to35%
and28% of the other groups. It is not yet clear whether this in turn reflects
grater cancer associated mortality from this group.
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