Taccaoside induces apoptosis in hepatocellular carcinoma cell lines

OBJECTIVE: Taccaoside, a steroidal saponin, has been shown to be cytotoxic, although the mechanism of cytotoxicity remains unclear. This study examined the effect of taccaoside on the human hepatocellular carcinoma (HCC) cell lines SMMC-7721 and Bel-7404. METHODS: The antiproliferative effect of taccaoside were measured using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. Cells were stained with Hoechst 33258 to observe morphology. Cell cycle and apoptosis were analysed by flow cytometry. Caspase activation was detected using specific assays, and PARP, Bax and Bcl-2 expression were analysed using western blotting. RESULTS: Taccaoside showed antiproliferative effect on HCC cell lines growth in a concentration- and time-dependent manner. Taccaoside arrested cell cycle in the G2/M phase and induced caspase-dependent apoptosis. Western blotting indicated that taccaoside upregulated Bax expression and downregulated Bcl-2 expression. PARP cleavage was observed following taccaoside treatment. CONCLUSIONS: This study showed that taccaoside may inhibit HCC cell proliferation by inducing apoptosis.