Effect of ZOL on BV173 leukemic cell growth. BV173 cells were exposed to 0 μM (•), 1 μM (▴), 5 μM (▪), 10 μM (□), 20 μM (x), or 30 μM (○) ZOL (A), whereas HL60 cells (B) were exposed to 0 μM (•), 5 μM (▴), 25 μM (▪), 50 μM (□), 100 μM (x), or 150 μM (○), respectively. Cells were counted by the trypan blue dye exclusion method. Data are presented as means ± SDs of at least 3 independent experiments.