LncRNA EPIC1 Promotes Cancer Cell Proliferation and Inhibits Apoptosis in Gallbladder Cancer Interacting with lncRNA LET

Abstract Background: LncRNA EPIC1 is likely involved in human cancer by promoting cell cycle progression. Our study was carried out to investigate the involvement of EPIC1 in gallbladder cancer (GBC). Methods: Expression levels of EPIC1 in two types of tissues (GBC and paracancerous) and plasma were measured by performing qPCR. GBC-SD and SGC-996 cells were transfected with LET and EPIC1 expression vectors. Results: In the preset study we found that EPIC1 was upregulated in tumor tissues than in paracancerous tissues of GBC patients, and plasma levels of EPIC1 were significantly correlated with levels of EPIC1 in tumor tissues. LncRNA LET was downregulated in tumor tissues than in paracancerous tissues and was inversely correlated with EPIC1 in both tumor tissues and paracancerous tissues. Overexpression of EPIC1 led to downregulated LET, and LET overexpression also mediated the downregulation of EPIC1. EPIC1 led to accelerated GBC cell proliferation and inhibited apoptosis. Overexpression of LET played opposites roles. In addition, overexpression of LET also attenuated the effects of EPIC1 overexpression on cancer cell proliferation and apoptosis. Conclusion: Therefore, therefore, lncRNA EPIC1 may promote cancer cell proliferation and inhibit apoptosis in GBC by interacting with LET.