ABSTRACT
@#Objective: To explore the mechanism of lncRNA XIST (XIST) regulating the biological behaviors of colorectal cancer HCT-8 cells via miR-32-5p/EZH2 (enhancer of Zeste homolog 2) axis. Methods:Atotal of 28 pairs of cancer tissues and corresponding para-cancerous tissues form colorectal cancer patients with complete clinical data were collected from the Colorectal and Anal Surgery, Xiangya Hospital of Central South University during July 2014 and August 2018. The expression levels of lncRNA XIST and miR-325p in colorectal cancer tissues and cell lines were detected by qPCR. The targeted relationship between lncRNA XIST, miR-32-5p and EZH2 was verified by dual luciferase reporter gene, and the expression level of EZH2 was further detected by WB. The proliferation, migration and apoptosis of HCT-8 cells were detected by CCK-8, Transwell and flow cytometry with Annexin V-FITC/PI staining, respectively. Results: lncRNAXIST was highly expressed in colorectal cancer tissues and cell lines with the highest expression in HCT-8 cells (P<0.05 or P<0.01). Dual luciferase reporter gene assay validated that lncRNA XIST negatively regulated miR-32-5p (P<0.05), and EZH2 was a target gene of miR-32-5p. Knockdown of lncRNAXIST inhibited proliferation and migration and induced apoptosis of HCT-8 cells (P<0.05 or P<0.01). Further experiments demonstrated that knockdown of lncRNA XIST up-regulated the expression of miR-32-5p and further down-regulated the expression level of EZH2, thereby inhibiting the proliferation and migration of HCT-8 cells and inducing apoptosis. Conclusion: lncRNAXIST promotes proliferation, migration and inhibits apoptosis of HCT-8 cells via miR-325p/EZH2 axis.