Fig. 6.

β-Elemene enhanced cisplatin-induced caspase activation in A2780/CP cells. Cells were treated with β-elemene alone (50 μg/ml), cisplatin alone (20 μM), or the combination of both drugs for 24 or 48 h. Untreated cells were used as the control. Cell lysates were prepared and assayed for caspases activities. The relative caspase activity was determined by calculating the fold increase relative to caspase activity in untreated cells. Caspase-3 (a), caspase-8 (b), and caspase-9 activities (c) are shown. ELE 50, β-elemene alone; CDDP 20, cisplatin alone; ELE 50 + CDDP 20, the combination of β-elemene and cisplatin. Data are the mean ± SD of three separate experiments. ^#P <0.01 and ^##P <0.05 compared with untreated cells, and *P <0.01 and **P <0.05 compared with β-elemene alone or cisplatin alone. d Western blot analysis of caspase-9 cleavage. Cell lysates were prepared after 24 or 48 h of drug treatment at the indicated concentrations. Proteins (60 μg) were resolved by SDS-PAGE, transferred to nitrocellulose membrane, and probed with appropriate primary and secondary antibodies. Proteins were visualized by enhanced chemiluminescence. Equal protein loading was verified by using an anti-β-actin antibody