Anti-tumor roles of both strands of the duplex: their targets and are involved in the pathogenesis of renal cell carcinoma.

Recent studies revealed that some passenger strands of miRNAs acted as anti-tumor or oncogenic miRNAs in cancer cells. In this study, we focused on (the passenger strand) and (the guide strand) based on microRNA (miRNA) expression signatures of cancer cells. Both and were downregulated in renal cell carcinoma (RCC) tissues and low expression of these miRNAs was significantly associated with poor prognosis. Cancer cell proliferation, migration and invasive abilities were significantly inhibited by ectopic expression of and . To identify their oncogenic targets, we applied a combination of genome-wide gene expression and miRNA database analyses. We focused on spindle and kinetochore-associated proteins, and and demonstrated direct regulation of by and by in RCC cells. Our present data demonstrated overexpression of in RCC clinical specimens. Moreover, the study showed that the / axis contributed to cancer cell aggressiveness. Analytic strategies based on anti-tumor miRNAs, including passenger strands of miRNAs, are effective approaches for the elucidation of the molecular pathogenesis of RCC.