摘要OBJECTIVE Metastasis-associated in colon cancer-1 (MACC1) is an oncogene that has been newly identified. It promotes tumor proliferation and invasion via the MET pathway. Our study investigated the effects of Saikosaponin-b(SS-b) on the proliferation and apoptosis of HepG2 cells and its regulation on MACC1/c-Met/Akt signaling pathway. METHODS HepG2 cells were treated with SS-b (10-800 g·L-1) for 48 h in vitro. The CCK-8 assay was used to assess cell proliferation, and cell apoptosis was determined by Hoechst33258 staining, AnnexinⅤ/PI staining and caspase 3 assay. RT-PCR was used to examine the expression of MACC1, c- MET and hepatocyte growth factor (HGF) mRNA. MACC1 protein was detected by Western blot and immunohistochemistry. The protein expressions of p-c-MET, c-MET, p-AKT, AKT, p-BAD, BAD were measured by Western blot. RESULTS SS-b inhibited the growth of HepG2 cells in dose-dependent way and induced cell apoptosis significantly. HepG2 cells showed karyopyknosis, fragmentation and fluorescence highlight in SS-b treatment group. FCM results showed that apoptosis rate of HepG2 cells increased with SS- b concentration. The immunofluores?cence results showed that the MACC1 expression decreased significantly in HepG2 cells treated with SS-b. The expression levels of MACC1, c-MET and HGF mRNA in HepG2 cells were significantly inhibited by SS-b. SS-b also significantly decreased the protein expressions of MACC1, p-c-MET and p-AKT while increased the expression of p-BAD and caspase 3 in HepG2 cells(P<0.05). CONCLUSION SS-b inhibited the proliferation and induced the apoptosis of HepG2 cells by targeting the MACC1/c-Met/Akt signaling pathway.