Effect of TRAIL on Expression of Multidrug Resistance Gene GST-π in Drug-resistant Human Gastric Cancer Cell Line SGC7901/VCR / 胃肠病学

ABSTRACT

Background:Multidrug resistance of tumor cells is one of the important factors that cause failure of chemotherapy in advanced gastric cancer. Tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)may enhance the killing effect of chemotherapeutics on tumor cells,and reverse drug-resistant cell lines to sensitive cell lines,but its mechanism is not yet clear. Aims:To study the effect of TRAIL on expression of multidrug resistance gene glutathione S-transferase-π(GST-π)in drug-resistant human gastric cancer cell line SGC-7901 / VCR and the potential mechanism of TRAIL in reversing multidrug resistance of gastric cancer cells. Methods:SGC-7901 / VCR cells were treated with TRAIL in different doses (50,100,200 and 400 μg/ L)for 48 hours. After treatment,expression of GST-π mRNA in SGC-7901 / VCR cells and concentration of GST-π in culture supernatant were detected by RT-PCR and ELISA,respectively. Results:TRAIL could inhibit mRNA expression and protein secretion of GST-π in SGC-7901 / VCR cells in a dose-dependent manner within a certain range(≤200 μg/ L). The relative expression levels of GST-π mRNA in 50,100,200 and 400 μg/ L TRAIL groups were 0. 89 ± 0. 04,0. 77 ± 0. 08,0. 65 ± 0. 06 and 0. 61 ± 0. 03,respectively,and the concentrations of GST-π in culture supernatant in these groups were(57. 56 ± 1. 19)ng/ mL,(56. 30 ± 0. 80)ng/ mL,(31. 41 ± 1. 65)ng/ mL and (30. 80 ± 1. 34)ng/ mL,respectively,all were significantly lower than those in control group[1. 01 ± 0. 13 and(58. 62 ± 1. 38)ng/ mL,P all < 0. 05]. Conclusions:TRAIL may play a potential role in reversing multidrug resistance of gastric cancer cells through down-regulating GST-π expression.