SNHG6 interacted with miR-325-3p to regulate cisplatin resistance of gastric cancer by targeting GITR

Background: Cisplatin resistance results in the failure of platinum-based chemotherapy and relapse of gastric cancer. We aimed to investigate the potential regulating role of SNHG6/ miR-325-3p/GITR in reversing cisplatin resistance. Patients and Methods: A total of 137 gastric cancer patients were recruited. qRT-PCR and ELISA were used to test the expression of target genes. CCK-8 and caspase 3/7 kit were used to test the cell viability and apoptosis rate. Dual luciferase reporter gene and RNA-pull down assay were used to investigate the potential interaction between target genes. Results: SNHG6 and GITR were up regulated in gastric cancer; however, miR-325-3p was down-regulated. Besides, SNHG6, miR-325-3p and GITR expression were associated with gastric cancer prognosis. Then, we found that GITR and SNHG6 promoted proliferation and inhibited apoptosis of MKN45 and MKN45 cisplatin resistance cell line; however, miR-325- 3p inhibited proliferation and promoted apoptosis of these cell lines. Furthermore, SNHG6 might bind to miR-325-3p to regulate its expression, and miR-325-3p directly interacted with the 3`UTR of GITR. Conclusion: SNHG6 binds to miR-325-3p, which directly interacted with GITR to regulate cisplatin resistance of gastric cancer.