Berbamine suppresses cell proliferation and promotes apoptosis in ovarian cancer partially via the inhibition of Wnt/β-catenin signaling

Ovarian cancer is a common and lethal cancer affecting women globally. Berbamine is a natural compound from the plant Berberis amurensis, which is used in Chinese traditional medicine. Recent studies have shown the anti-tumor effects of berbamine in several types of cancers but not in ovarian cancer. In the present study, we investigated the potential anti-tumor effects of berbamine in ovarian cancer and explored the underlying molecular mechanisms. Berbamine suppressed the cell viability of ovarian cancer cells in a concentration-dependent manner as revealed by methyl thiazolyl tetrazolium assay. Berbamine also suppressed the cell growth and invasion of ovarian cancer cells as measured by colony formation and cell invasion assays, respectively. Flow cytometry experiments showed that berbamine increased cell apoptotic rate and induced cell cycle arrest at G(0)/G(1) phase in ovarian cancer cells. Western blot analysis showed that berbamine increased the protein levels of cleaved caspase-3, cleaved caspase-9, Bax, and decreased the protein level of Bcl-2 in ovarian cancer cells. Quantitative real-time PCR and western blot analysis demonstrated that berbamine treatment inhibited the Wnt/beta-catenin signaling in ovarian cancer cells. The inhibitory effects of berbamine on cell viability and invasion of ovarian cancer cells can be partially reversed by lithium chloride (LiCl) treatment. Growth of tumors developed from SKOV3 cells was significantly suppressed in berbamine-treated group, and berbamine treatment enhanced caspase-3 and -9 cleavage and reduced beta-catenin protein level in tumor tissues. In summary, berbamine exerts its anti-cancer effects in vitro and in vivo via induction of apoptosis, partially associated with the inhibition of Wnt/beta-catenin signaling.