Effects of BL-038 on caspase activation: (A) JJ012 cells were treated with BL-038 (5 μM) for the indicated times. PARP, procaspase 3, cleaved-caspase 3, procaspase 9, cleaved-caspase 9 and β-actin levels were analyzed by Western blot; (B,C) JJ012 cells were treated with BL-038 for 24 h, and the caspases activities were examined; and (D) JJ012 cells were pre-treated with the indicated inhibitors for 30 min, then incubation with BL-038 (5 μM) for 24 h. The percentage of apoptotic cells were then analyzed by flow cytometric analysis of PI-stained cells. Results are expressed as the mean ± SEM. * p < 0.05 compared with controls. # p < 0.05 compared with BL-038 treated groups.