Inhibitory Effects of the Alcoholic Extracts of Sarcopyramis Nepalensis Wall Containing Serum on HepG2 Cells Based on the mTOR Signalling Pathway

OBJECTIVE To investigate the effects of Sarcopyramis nepalensis Wall. medicated serum on the gene related to mTOR signaling pathway, cell proliferation, and apoptosis in hepatocellular carcinoma HepG2 cells.

METHODS Hepatocellular carcinoma HepG2 cells were cultured in vitro and divided into control group, blank serum group and high-, medium-, and low-dose of Sarcopyramis nepalensis Wall. medicated serum groups. Cell proliferation was assessed using the CCK-8 assay and colony formation assay. Cell viability was observed using FDA staining, and cell invasion ability was evaluated using the Transwell assay. Apoptosis was detected using Annexin V-FITC/PI double staining. The protein expression levels of caspase-9, caspase-3, Bax, Bcl-2, mTOR, and p-mTOR were measured by Western blotting analysis.

RESULTS Compared with control group, all dose of Sarcopyramis nepalensis Wall. medicated serum groups significantly reduced the proliferation capacity and viability of HepG2 cells(P<0.01), inhibited the colony formation rate and invasion ability of HepG2 cells(P<0.01), and induced apoptosis of HepG2 cells. The Sarcopyramis nepalensis Wall. medicated serum groups upregulated the protein expression of caspase-9, caspase-3, Bax, and p-mTOR/mTOR(P<0.01) and downregulated the protein expression of Bcl-2(P<0.01), showing a certain concentration-dependent effect. Furthermore, the medium-dose of Sarcopyramis nepalensis Wall. medicated serum combined with the mTOR inhibitor Rapamycin synergistically enhanced the protein expression of caspase-9, caspase-3, Bax, and p-mTOR/mTOR(P<0.01) and downregulated the protein expression of Bcl-2(P<0.01).

CONCLUSION  The Sarcopyramis nepalensis Wall. medicated serum effectively inhibite the proliferation and invasion of HepG2 cells, promote cell apoptosis, and suppress the phosphorylation of mTOR protein in the mTOR signaling pathway. Additionally, it upregulate the expression of pro-apoptotic proteins caspase-9, caspase-3, and Bax, while downregulating the expression of the anti-apoptotic protein Bcl-2.