MicroRNAs (miRNAs) are small, non-coding RNA molecules that epigenetically regulate gene expression. Recently, it has been shown that miRNAs are heavily involved in renal carcinogenesis by controlling the expression of proteins related to renal cell carcinoma (RCC) and, thus, the activity of key signaling pathways involved in pivotal cell processes. Areas covered: This review focuses on the role of miRNAs as emerging biomarkers in RCC. We summarize the oncogenic and/or tumor-suppressive functions of miRNAs as well as the strong clinical information that these RNA molecules provide. Expert commentary: miRNAs that could be either exploited as standalone biomarkers or integrated into molecular signatures with high clinical interest should be considered as ideal for diagnostic purposes and accurate molecular classification of renal tumors. Furthermore, miRNAs could serve as prognostic biomarkers, predicting disease-free and overall survival of RCC patients and, thus, reducing over- and/or under-treatment of patients. miRNA may also be used as predictors of patients' response to targeted therapy with tyrosine kinase inhibitors, contributing to the decision-making process for the selection of the appropriate treatment plan.
Keywords: Diagnosis; biomarkers; miRNA; molecular classification; prognosis; tumor markers.