Bufalin-induced caspase-3 activity was reduced by miR-181a inhibitor transfection in PC-3 cell. A. Caspase-3 activity was assayed by a caspase-3 substrate cleavage based luminescence kit. Histogram showed the background subtracted luminescence value. P values were calculated byStudent’s t-test, based on three replications. B. Western blot showed that the active form of caspase-3 was reduced by miR-181a inhibitor transfection. β-actin served as internal control; miR-NC indicated a negative miRNA control.