Tumor suppressive miR-509-5p contributes to cell migration, proliferation and antiapoptosis in renal cell carcinoma

The aim of this study was to determine the expression and function of miR-509-5p in renal cell carcinoma (RCC). In this research, we have conducted quantitative real-time polymerase chain reaction (qRT-PCR) assay to determine the expression level of miR-509-5p in tissues and plasma from renal cell carcinoma patients. We preformed in vitro migration scratch assay, flow cytometry analysis and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to determine the exact function of miR-509-5p. We evaluated the expression level of miR-509-5p in RCC tissues and paired adjacent normal tissues from 42 patients and found that miR-509-5p expression in 42 RCC specimens was significantly down-regulated compared to that in adjacent normal tissue. Furthermore, the level of miR-509-5p in RCC patients' plasma was significantly lower than that in control plasma. In addition, the overexpression of miR-509-5p suppressed the proliferation of RCC cell (786-0), induced cell apoptosis and inhibited cell migration in vitro. In this study, we have shown that miR-509-5p played an important role in RCC by inhibiting cell proliferation and migration and by promoting cell apoptosis. In addition, miR-509-5p expression was significantly lower in RCC patient plasma compared to that in normal individuals.