Mechanism Study Of Paris Saponin-induced Autophagy And Apoptosis Against Breast Cancer Cells

Paris saponins possess anticancer,anti-inflammatory,and antiviral effects.However,the anticancer effect of Paris saponins has not been well elucidated and the mechanisms underlying the potential function of Paris saponins in cancer therapy are needed to be further identify.In this study,we report that saponin compounds isolated from Paris polyphylla exhibited antitumor activity against breast cancer cell lines,MCF-7 and MDA-MB-231.MCF-7 and MDA-MB-231 cells were cultured in DMEM medium,we investigated the cytotoxicity of XA-2 on MCF-7 and MDA-MB-231 cells via MTT assay,we examined the cell apoptosis induced by XA-2 in MCF-7 and MDA-MB-231 cells using the flow cytometry.At the same time,we examined the cell viability and cell apoptosis using MTT assay and flow cytometry assay when we pre-treated cells with autopagy inhibitions 3-MA and BFA for 4h and then treated with XA-2 for 48 h.we used Western-blot to exam effects of XA-2 on apoptosis pathways proteins like Caspase3,Caspase9 and PARP,AKT/ mTOR pathways proteins like P-Akt,P-mTOR,P-P70S6 k and P-4EBP1;and also we examined the effect of XA-2 on autophagy proteins LC3 and p62 through Western-blot.We investigated autophagic vacuoles in MCF-7 and MDA-MB-231 cells by transmission electron microscope analysis and Acridine orange staining.Our results indicate that XA-2 is an efficient anticancer compound in vitro,The IC50 values of XA-2 at 48 h were about 2.54?M in MCF-7 and 2.28?M MDA-MB-231 cells.XA-2 induced cell apoptosis in both cell lines and we found the cleavage of caspase-3,caspase-9 and PARP in a dose-dependent way after XA-2 treatment for 48 h.Futher more,we investigate that XA-2 induce autophagy in both breast cells and XA-2-induced autophagy promotes apoptosis in breast cancer cells.Additionally,the Akt/mTOR signaling pathway is involved in XA-2-induced autophagy.