Calycosin induces apoptosis in human ovarian cancer SKOV3 cells by activating caspases and Bcl-2 family proteins.

Calycosin is widely used as a natural active compound for its anti-oxidative and anti-inflammation activity. Recently, several studies have shown that calycosin can inhibit growth and induce apoptosis in human cancer cell lines; however, the mechanisms are not completely clarified yet. In this study, we investigated the effects of calycosin on human ovarian carcinoma SKOV3 cells, as well as the mechanisms. SKOV3 cells were treated with calycosin at a series of concentrations for different times. In vitro, the MTT assay showed that calycosin had obvious anti-proliferation effects on SKOV3 cells in a dose- and time-dependent manner. Cell morphological changes which expressed by Hoechst 33258 staining were compared with apoptotic changes detected by fluorescence microscope. Compared with control group, the group treated with calycosin showed a significant increase in apoptosis rate. Expression of apoptosis related Bax/Bcl-2 and caspases proteins were detected by Western blotting. The results demonstrated that calycosin up-regulated the Bax/Bcl-2 ratio and cleaved caspase-3, cleaved caspase-9 expression in a dose-dependent manner. In summary, calycosin might exert anti-growth and induce-apoptosis activity against ovarian cancer SKOV3 cells through activating caspases and Bcl-2 family proteins, therefore presenting as a promising therapeutic agent for the treatment of ovarian cancer.