Figure 4.
Involvement of caspases in the induction of apoptosis in human leukemia cells. Cells were incubated in the presence of the indicated concentrations of compounds 3g, 3h, 3j, or 4a, and cell lysates were assayed by immunoblotting for the cleavage of pro-caspases-9, -8, -6, and -3, poly(ADP-ribose) polymerase (PARP), and cytochrome c release. β-Actin was used as a loading control.