Silencing miR-454 suppresses cell proliferation, migration and invasion via directly targeting MECP2 in renal cell carcinoma.

Renal cell cancer (RCC) is one of the most common malignant tumors of the urinary system. MicroRNA-454 (miR-454) has been reported to play an important role in various cancer progressions, such as hepatocellular carcinoma, breast cancer and glioblastoma. Nevertheless, its effect on RCC still remains unknown. We aimed to investigate the biological function and underlying mechanisms of miR-454 in RCC. The expressions of miR-454 and MECP2 in RCC tissues were assessed using data from TCGA database and our own clinical samples. Functional experiments Cell Counting Kit-8 (CCK-8), colony formation, wound healing and Transwell assays were applied to detect the effects of miR-454 and MECP2 in RCC. The interaction between miR-454 and MECP2 was assessed by western blot and luciferase reporter assays. MiR-454 was upregulated in RCC tissues and cell lines compared with matched adjacent normal tissues and the normal kidney tubular epithelial cell line HK-2. MiR-454 inhibition and methyl-CpG binding protein 2 (MECP2) overexpression could both decrease the proliferative, migrative and invasive abilities of RCC cells. Higher expression of miR-454 predicted a poor overall survival (OS) (HR: 1.8; P < 0.05), while MECP2 level was positively related with RCC OS (HR: 0.55; P < 0.05) and disease-free survival (HR: 0.56; P < 0.05). Mechanistically, we showed that miR-454 could directly target the downstream gene MECP2. Our findings indicated that miR-454 accelerates RCC progression via suppressing MECP2 expression, which may provide a novel potential target of RCC treatment in the future. AJTR