Reversion of the resistance of gastric cancer SGC7901/DDP cells by miRNA-200c and its related mechanism

Objective:To explore the effect of microRNA-200c(miRNA-200c)in reversing cisplatin(DDP)resistance of gastric cancer SGC7901/DDP cell line and elucidate its related mechanisms.Methods:The real-time fluorescence quantitative PCR(RFQ-PCR)was used to detect miRNA-200c expression in SGC7901 cells,DDP-resistant SGC7901/DDP cells,and miRNA-200c transfected SGC7901/DDP cells.The difference in miRNA-200c expression was compared between the groups.Drug sensitivity to DDP after transfection was tested using MTT assay.The protein expression of bax,phosphatase and tensin homology deleted on chromosome ten(PTEN)and E-cadherin(E-cad)after transfection were detected by Western blotting.Results:The relative miRNA-200c expression level in SGC7901/DDP cell line was significantly lower than that in SGC7901 cell line(P0.05).The miRNA-200c expression was significantly increased at 24 h after transfection than that of the negative control group(P0.05).The half inhibition concentration(IC50)of DDP was significantly lower in miRNA-200c precursor tansfected group than that in negative control group(P0.05).Furthermore,the relative protein expressions of bax,PTEN and E-cad in miRNA-200c precursor transfected group were significantly higher than those in negative control group(P0.05).Conclusion:MiRNA-200c reverses the resistance of SGC7901/DDP cells to DDP through up-regulating the expressions of E-cad,PTEN and bax proteins.