miR-566 functions as an oncogene and a potential biomarker for prognosis in renal cell carcinoma

Background: Renal cell carcinoma (RCC), a heterogeneous type of cancer originating from the nephron, occupies approximately 3.9% of new carcinomas, with an increasing incidence in the past two decades. The most common subtype of renal cell carcinoma is clear cell RCC (ccRCC). Though surgery and other treatments are applied to RCC, it has the highest recurrence rate and mortality rate among the genitourinary cancers. As the study progressed, miRNAs are found to be the biomarkers for tumor diagnosis, prognosis and the targets for tumor management. Methods: In present study, RT-qPCR, wound scratch assay, cell proliferation assay, transwell assay and flow cytometry assay were performed to ascertain miR-566 expression level and its proliferation, migration and apoptosis in RCC. Moreover, we analyzed the relation between miR-566 expression and clinicopathological variables or overall survival from the 42 formalin-fixed paraffin-embedded (FFPE) renal cancer samples. We further evaluate prognostic values of miR-566 expression. Results: miR-566 is up-regulated in RCC tissue samples and renal carcinoma cell lines. miR-566 promotes cell proliferation, mobility and inhibits cell apoptosis in 786-O and ACHN cell lines. Cox proportional hazard regression analysis indicates that low expression of miR-566 patients have a remarkable longer overall survival in the univariate and multivariate analysis. The Kaplan-Meier survival curves show that the low expression of miR-566 patients have a remarkable longer overall survival. Conclusions: The results of the current study demonstrate that oncogene miR-566 is a potential biomarker not only for diagnosis but also for prognosis for RCC.