12th Congress of the European Hematology ... - Haematologica

12 th Congress of the European Hematology Association
Myelodysplastic syndromes
0426
CYTOGENETIC HYBRIDIZATION BY ARRAY COMPARATIVE GENOMIC HYBRIDIZATION
AND FLUORESCENCE IN SITU HIBRIDIZATION OF MESENCHYMAL STEM CELLS FROM
PATIENTS WITH MYELODYSPLASTIC SYNDROMES
O. López Villar, 1 F. Martín Sánchez-Guijo, 1 J.L. García, 2 E. Villarón, 1
N. López-Holgado, 1 J.A. Pérez Simón, 1 J. San Miguel, 1 M.C. Cañizo1 1 Hospital Universitario de Salamanca, SALAMANCA; 2 Centro de Investigación
del Cancer, SALAMANCA, Spain
Background. Myelodysplastic syndromes (MDS) are a group of clonal
disorders of hematopoietic stem cell (HSC). The hematopoietic microenvironment
plays a role in the physiology of the hematopoietic system,
and mesenchymal stem cells (MSC) are a key component of this
microenviroment. Recently, some data has been published showing that
these MSC could be involved in the MDS pathophysiology. Moreover,
the presence of cytogenetic aberrations on these cells is controversial.
The studies performed, so far, have used conventional cytogenetics and
fluorescent in situ hybridization (FISH). Aims. To characterize bone marrow
derived MSC from patients with MDS, by two approaches: array
comparative genomic hybridization (array-CGH), and FISH, in order to
know genomic changes in these cells and whether they could show
clonal cytogenetic alterations. Methods. 13 patients with untreated MDS
were included in the study. The median age was 72 years (range: 54-89)
The male/female ratio was 7/6. Diagnosis of MDS was established
according to the WHO classification as follows: 5q- syndrome (n=7),
refractory anemia (RA) (n=2), refractory anemia with ringed sideroblasts
(RARS) (n=1) and refractory anemia with excess blasts type II
(RAEB-II) (n=3). Standard cytogenetic and FISH studies on hematopoietic
cells were performed at diagnosis according to standard methods
with the following Results. 5q- (n=7), 8 trisomy (n=2) and normal cytogenetics
(n=4). MSC were obtained by plating mononuclear cells from
BM and cultured in a DMEM + 10% fetal calf serum medium, and
expanded following standard procedures, until the third passage, when
adherent MSC were harvested to perform cytogenetic and phenotypical
studies. Array-CGH was performed in 11 cases and FISH studies in
5 (3 cases had both techniques). To perform Array-CGH a total of 3500
genomic targets were compounded from RP-11 libraries. The PCR products
after purification were arrayed onto glass slides using a BioRobot.
DNA was labelled, denaturalised and hybridizated. Images were
analysed by using GenePix Pro 4.0 software. Results. MSC showed characteristic
phenotypical data and their purity was 91%. In all cases
analysed MSC showed DNA genomic changes. The most frequent aberrations
were 1q24q32 region gains, in 72% of the cases, and 1p13 and
11q12 losses in 55% of patients. When the cells from patients carrying
the 5q- alteration were analysed we observed that in half of them 5q
losses were present in MSC. FISH analysis was carried out in MSC from
3 patients with 5q- and 2 patients diagnosed of RARS and RAEB-II, who
had trisomy 8, and the same changes were present in 11% of MSC.
Conclusions. We conclude that 100% of MSC from MDS show chromosomal
aberrations when CGH arrays are used for this analysis. Even
clonal specific MDS alterations are also shown when both, FISH and
array-CGH analysis are performed. This is the first study that has
showed the gains and losses in DNA of MSC from MDS by Array-CGH.
MSC aberrations were also confirmed by FISH.
0427
HAS TREATMENT WITH EPO+/- G-CSF AN IMPACT ON PROGRESSION TO AML AND
SURVIVAL IN LOW/INT-1-RISK MDS? A COMPARISON BETWEEN FRENCH-EPO PATIENTS
AND THE IMRAW DATABASE
S. Park, 1 S. Grabar, 1 C. Kelaidi, 2 O. Beyne-Rauzy, 3 F. Picard, 1
D. Vassilieff, 1 V. Coiteux,4 G. Leroux, 4 P. Leppeley, 4 H. Dombret, 4
M.T. Daniel, 4 S. Cheze, 4 B. Mahe, 4 L. Ades, 2 A. Ferrant, 4 C. Ravoet, 4
N. Vey, 4 M. Escoffre-Barbe, 4 L. Aljassem, 4 K. Bourgeois, 5
P. Greenberg, 6 P. Fenaux, 2 F. Dreyfus1 1 Cochin Hospital, PARIS, France; 2 Hôpital Avicenne, BOBIGNY, France; 3 Hôpital
de Purpan, TOULOUSE, France; 4 GFM, PARIS, France; 5 University of
Rochester Medical Center, NEW YORK, USA; 6 Stanford University Cancer
Center, STANFORD, USA
Backround. We recently reported the results of treatment with EPO
±G-CSF in 419 patients (Park, ASH 2006, n°522) treated between 1998
158 | haematologica/the hematology journal | 2007; 92(s1)
and 2005 in France. Aims. Here we compared the outcome (progression
to AML and survival) of these French patients (French-EPO) to MDS
patients who received only supportive care (IPSS/IMRAW database).
Methods. We restricted the analysis to patients with low and int-1 IPSS
and also excluded CMML, RAEB-t, unclassifiable MDS, poor- risk karyotype,
and 3q26 deletion, that are classically not the best candidates for
EPO treatment. Progression to death and progression to AML since MDS
diagnosis were compared using Kaplan-Meier estimates and Log-rank
test. Multivariate cox analyses were adjusted for the main known prognostic
factors (age at diagnosis, sex,% of marrow blasts, FAB diagnosis,
IPSS score and karyotype). EPO introduction was modeled as a timedependent
covariate (dependent on the delay between MDS diagnosis
and EPO introduction). Results. In the French-EPO (F), 284 pts, and in the
IMRAW database (I), 447 pts were finally compared. Median follow-up
was 26 months (IQR 13-53) and 33 months (IQR 15-61) in French-EPO
and IMRAW, respectively. Both cohorts were different for: age (median
71 vs 68 y, p=0.0013),% of blasts (median, 3% [IQR 2-5] vs 2% [IQR 1-
4], p=0.0006), FAB diagnosis [RA= 39% vs 56%, RAEB= 22% vs 17%,
and RARS=38% vs 26%, (p