Antitumor Effect of Periplocin in TRAIL-Resistant Human Hepatocellular Carcinoma Cells through Downregulation of IAPs
Figure 3
Treatments of periplocin and/or TRAIL activate DR4, FADD, and proapoptotic proteins in HCC cells. (a) The effect of periplocin treatment on the expression of DR4, DR5, and FADD was analyzed by western blot. (b) HA22T/VGH cells were treated with different doses of the indicated compounds for 24 h. Expressions of both proforms and cleaved forms of caspase-8, caspase 3, PARP, and BID were analyzed by western blotting. (c) Huh-7 cells were treated with different concentrations of the indicated compounds for 4 h or 24 h. The expression of caspase-8, caspase-9 was analyzed after indicated compounds treatment for 4 h, and the expression of caspase 3, PARP, BID was analyzed after the treatment of indicated compounds for 24 h. (d) HA22T/VGH cells were pretreated with 20 μM or 50 μM inhibitors against caspase-3 (Z-DEVD-FMK), caspasae-8 (Z-IETD-FMK), caspase-9 (Z-LEHD-FMK), and general caspase inhibitor (Z-VAD-FMK) for 3 hours prior to periplocin and/or TRAIL treatment. Cell viability was examined by MTT assay.
