Haematopoietic response and bcl-2 expression in patients with acute myeloid leukaemia

Bcl-2 expression, the number of apoptotic cells and the growth and differen tiation of early bone marrow progenitor cells were studied in patients with confirmed diagnosis of acute myeloid leukaemia (AML). Bone marrow cells fr om normal individuals were used as controls. We observed an increased perce ntage of bcl-2(+) mononuclear bone marrow cells expression in AML patients in relation to controls (p = 0.002). Accordingly, the number of apoptotic c ells was reduced (p = 0.001) and there was a negative correlation between b cl-2 expression and the number of apoptotic cells (r = -0.664, p < 0.001). In addition, bcl-2 expression was significantly increased in the chemothera py resistant group in relation to the responsive group (p = 0.03). Lower ra te of survival was observed in the group of AML patients with autonomous pr oliferation (p = 0.01). These results suggest that a high bcl-2 expression and the presence of autonomous proliferation are related to a poor prognosi s in AML.