MALAT1 accelerates the development and progression of renal cell carcinoma by decreasing the expression of miR‐203 and promoting the expression of BIRC5

Objective We aimed to investigate the roles of the lncRNA MALAT1 in renal cell carcinoma (RCC) progression. Methods qRT‐PCR was used for the assessment of BIRC5, miRNA‐203 and MALAT1 expression. Furthermore, the targeted relationships between miR‐203 and BIRC5, as well as MALAT1 and miR‐203, were predicted by the miRanda/starBase database and verified by dual‐luciferase reporter gene assay. The effects of MALAT1, miRNA‐203 and BIRC5 on cell proliferation, cell cycle, cell apoptosis, cell invasion and cell migration were studied by using CCK‐8, flow cytometry, transwell and wound healing assays, respectively. In addition, the effects of MALAT1 on RCC tumorigenesis were evaluated in vivo by nude mouse tumorigenesis. Results The expression levels of BIRC5 and MALAT1 were higher in RCC tissues and cell lines than in adjacent normal tissues and a normal renal cortex proximal tubule epithelial cell line. In contrast, the expression of miRNA‐203 in RCC tissues and cell lines was higher than that in adjacent normal tissues and a normal renal cortex proximal tubule epithelial cell line. BIRC5 and MALAT1 promoted cell proliferation yet decreased the percentage of RCC cells at G0/G1 phase. Conclusions Our study demonstrated that MALAT1 functions as a miR‐203 decoy to increase BIRC5 expression in RCC.