ABSTRACT
@# Objective: To investigate the mechanism of lncRNA XIST (XIST) on modulating gastric cancer progression via regulating miR-337-3p/HOXC8 axis. Methods: A total of 58 cases of gastric cancer tissues and corresponding para-cancerous tissues resected from March 2013 to January 2018 in Department of General Surgery, Kailuan General Hospital of Tangshan City were collected for this study; in addition, human gastric cancer cell lines (AGS, MGC803, HGC27) and human gastric mucosal GES-1 cells were also collected. qPCR was used to detect the expressions of XIST and miR-337-3p in above mentioned gastric tissues and cell lines. XIST-knockdown vectors, miR-337-3p mimics, miR-337-3p inhibitor and HOXC8-overexpression vectors were transfected into AGS cells. The proliferation and invasion of AGS cells were detected by CCK-8 and Transwell experiments respectively, and the expression levels of HOXC8, E-cadherin, N-cadherin and vimentin were detected by WB. The targeting relationships between XIST, miR337-3p and HOXC8 were verified by dual-luciferase reporter gene assay. Results: XIST was up-regulated in gastric cancer tissues and cell lines (all P<0.01). XIST knockdown significantly inhibited proliferation, invasion and EMT of AGS cells (P<0.05 or P<0.01). Moreover, XIST directly interacted with miR-337-3p and down-regulated its expression, while HOXC8 was the target gene of miR-3373p. Furthermore, XIST knockdown suppressed proliferation, invasion and EMT ofAGS cells through up-regulating the inhibitory effect of miR-337-3p on HOXC8 (P<0.05 or P<0.01). Conclusion: XIST knockdown can suppress the proliferation, invasion and EMT of AGS cells, which may be related with down-regulation of HOXC8 by targeting miR-337-3p.