BMS-214662–induced caspase-3 activation is a downstream effect of the mitochondrial pathway. (A) Representative dot plots of the measurement of caspase-3 activation after cotreatment of CD34⁺ CML cells with 250nM BMS-214662 and 50μM FMK-ZVAD (i). Conformational changes of Bax (clone 3) were measured in cells treated as indicated (n = 3, ii). (B) In situ trapping of initiator caspase using biotin-X-VAD-FMK in CD34⁺ CML cells after 24-hour treatment with BMS-214662 (250nM) showed immunoprecipitation of caspase-3, but not caspases-8 or -9 (n = 3).