Interestingly, as shown in Figure 5A, 72 h of RSV treatment, induces cleavage of Poly (ADP-ribose) polymerase (PARP), caspase-7 and caspase-3 in PC3 but not in EPN and EPN-PKM cells, confirming the knowledge that RSV induces apoptosis selectively in cancer cells. Here, CASP7 is linked to cancer.