[Effect of 2-chlorodeoxyadenosine, arabinoside cytosine and doxorubicin on acute myeloid leukemia clonogenic cell proliferation].

We examined the influence of 2-chlorodeoxyadenosine (2-CDA) in concentration 300 nM/l alone and in combination with cytosine arabinoside (ara-C; 10(-7) M/l and doxorubicine (drb; 1 microgram/ml) on the proliferation of acute myeloid leukemia (AML) clonogenic cells (L-CFU) in agar/liquid culture system. After preincubation of blast cells with 2-CDA or ara-C as a single agent the number of colonies was reduced, reaching 70% of control (p < 0.05). Exposure of AML blasts to drb resulted in a greater reduction of L-CFU proliferation than in experiments with 2-CDA or ara-C alone (p < 0.05). Coadministration of 2-CDA in conjunction with ara-C or drb, and additionally with ara-C and drb caused the inhibition of L-CFU growth in comparison with control experiments by 52%, 78% and 61%, respectively (p < 0.05). In further experiments we studied the effect of ara-C and drb together with 2-CDA in different concentrations (20, 100 or 300 nM/l). After preincubation with 2-CDA in concentration 20 nM/l no change in blast colony formation was observed in relation to controls which comprised ara-C and drb only (p < 0.05). The increase of 2-CDA concentration to 100 or 300 nM/l in combination with ara-C and drb significantly reduced the growth of AML clonogenic cells (p < 0.05). The greatest, 90%, inhibition of L-CFU proliferation was observed after the exposure of blast cells to ara-C, drb and 2-CDA in concentration 300 nM/l (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)