To explore the apoptotic effects and underlying mechanisms of nitidine chloride (NC) in epithelial ovarian cancer.
The MTT cell proliferation assay was used to detect the inhibitory effects of different concentrations of NC (0, 0.3125, 0.625, 1.25, 2.5, 5 and 10 μg/ml) in SKOV3 ovarian carcinoma cells. The number of apoptotic cells was observed by Hoechst staining and measured by flow cytometry. Quantitative PCR was used to measure the expression of Fas, Fas-associated death domain-containing protein (FADD), caspase-8 and caspase-3. RNA interference (RNAi) was used to determine whether caspase-8 played an important role in NC-induced apoptosis.
Nitidine chloride inhibited the proliferation of SKOV3 cells (IC50= 2.317 ± 0.155 μg/ml) after 24 h of treatment and induced apoptosis (15.9-64.3%). Compared with the control group, a significant increase in Fas, FADD, caspase-8 and caspase-3 gene expression was observed in the NC-treated groups (P < 0.05). After silencing caspase-8 by RNAi, the antiproliferative activity and pro-apoptotic activity of NC in SKOV3 cells decreased (P < 0.05).
Our study showed that NC induced apoptosis in SKOV3 cells by activating the Fas signalling pathway, and caspase-8 played an important role in this process.