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

derivative chromosome (4p16, 7p14, 13q14, and 11q13, respectively);
among them, only in one case the loss of miRNAs on the third derivative
was not associated with the miRNAs deletion mapped on chromosome
9. The most recurrent miRNAs deleted on der(9) were mir-219-2
(deleted in 100% of cases) and mir-199-b (lost in 67% of cases). It is
noteworthy that mir-219-2 neighbors and overlaps CpG-islands, suggesting
a potential role of this miRNA in CpG-island methylation. Conclusions.
Experimental studies indicate that miRNAs can function as
tumor suppressor genes or as oncogenes. In fact, in chronic lymphocytic
leukemia associated with del(13)(q14) it has been demonstrated that
the miRNAs loss can induce downregulation of the antiapoptotic BCL-
2 protein. The novel evidence that deletions on der(9) in CML are associated
with miRNAs loss may shed new light on the significance of
genomic sequences loss. Further studies are needed since it is known that
some microRNAs may have as many as a few thousand targets, so prediction
algorithms and strategies allowing large-scale screening of multiple
target genes are required.
0540
SEMEN ANALYSIS DURING IMATINIB THERAPY IN PATIENTS WITH CHRONIC MYELOID
LEUKEMIA
F. Maloisel, 1 A. Zamfir, 2 K Bennada, 2 A. Clavert3 1 Hôpitaux Universitaires, STRASBOURG; 2 Department of Hematology &
Oncology, STRASBOURG; 3 CECOS, STRASBOURG, France
Background. Imatinib is the main treatment of chronic myeloid
leukaemia and induces high rate of cytogenetic response and major
molecular response. The 5 years survival from IRIS trial is 87% and the
annual risk of relapse for responder patients is about 1% by year. Imatinib
is a strong inhibitor of bcr-abl, c-kit and PDGF-R, and could explain
sides effects related to the drug. C-kit is involved during spermatogenesis
and influenced the spermatogonies maturation. Imatinib induces
qualitative and quantitative deteriorations of spermograms in rats. Data
about qualitative and quantitative characteristics of spermograms from
patients treated with imatinib are lacking and sperm cryopreservation
before treatment is recommanded. Methods. Semen cryopreservation
was performed at diagnosis before treatment to every patient under 50
years of age. After information and fully consenting, patients aged >17
and