Thalidomide treatment reduces apoptosis levels in bone marrow cells from patients with myelodysplastic syndromes

We treated with thalidomide seven patients with primary MDS and observed reduction of the transfusion requirement in three cases and reduction of bone marrow blasts in one case. The apoptotic rate of bone marrow cells diminished significantly from a mean of 43.8% to a mean of 17.5%, whereas the proliferative activity did not change. Plasma TNF-α, bFGF, IL-1β levels decreased variably, whereas VEGF levels tended to increase. Matrix metalloproteinases 2 and 9 expression decreased in bone marrow cells of responders. A reduction of CD4 cells and an increase of NK cells was observed in the peripheral blood. Thus, thalidomide may produce a fairly good hematological improvement in erythroid series in MDS, with complex biological mechanisms.