Roles of GST-π and polβ Genes in Chemoresistance of Esophageal Carcinoma Cells

The main aim of this study was to investigate the roles of GST-π and polβ genes in the chemoresistance ofesophageal carcinoma cells. Eukaryotic expression vectors containing each gene were constructed and transfectedinto EC9706 cells, and the biological effects of the two genes assessed based on a resistance index. We additionallyinvestigated the in vitro and in vivo anti-resistance effects of GST-π and polβ genes using recombinant lentivirusescarrying siRNAs against the two genes. Our results showed that upregulation of GST-π and polβ genes suppresseschemosensitivity of esophageal carcinoma cells to cisplatin, while downregulation of these two genes with RNAitechnology reverses this chemoresistance. Multi-site injection of recombinant lentivirus targeting the GST-πgene into transplanted cDDP tumors effectively reversed their chemoresistant phenotype. However, the sametreatment against the polβ gene did not lead to significant efficacy against chemoresistance.