Abstract: Objective  To investigate the effect of resveratrol (RES) on the biological effects of SGC-7901/5-FU cells and its mechanisms. Methods The SGC-7901/5-FU cells were treated with RES at concentrations of 0 μmol/L, 10 μmol/L, 50 μmol/L, 200 μmol/L and 400 μmol/L, respectively, for 24 h, 48 h and 72 h, and then SGC-7901/5-FU cells were treated, with RES (100 μmol/L) and 5-FU (5 μmol/L), respectively or simultaneously, for 48 h. The cell proliferation was detected by CCK-8 method, the apoptosis by flow cytometry, and the cell morphology by immunofluorescence staining method. The mRNA expression levels of MDR1, Bcl2 and Caspase 3 were detected by RT-PCR, and the protein expression levels of P-gp, Bcl2 and caspase 3 were detected by Western blot. Results RES with different concentrations could inhibit the proliferation of SGC-7901/5-FU cells effectively, depending upon time and dose. The RES group, 5-FU group and combined group could induce apoptotic and morphology changes in SGC-7901/5-FU cells, which was most remarkable in the combined group(P<0.001). The expression levels of MDR1 mRNA and P-gp protein in RES group and combined group were decreased (P<0.05), which was more significant in combined group; the Bcl2 mRNA and protein expression levels were decreased in RES group, 5-FU group and combined group (P<0.001), while Caspase 3 mRNA and protein expression levels were increased (P<0.001), which was more pronounced in the combined group. Conclusions RES can inhibit the proliferation of SGC-7901/5-FU cells by down-regulating the expression of drug-resistance related gene MDR1/P-gp protein and induce cell apoptosis to reduce drug resistance.

Key words: Gastric cancer, Resveratrol, Drug resistance, Apoptosis