MicroRNA-27a functions as a tumor suppressor in renal cell carcinoma by targeting epidermal growth factor receptor

Numerous studies have suggested that microRNAs (miRNAs) are vital in the development of various types of human cancers, including renal cell carcinoma (RCC), and the regulation of tumor progression and invasion. However, the effect of miRNA-27a (miR-27a) on the tumorigenesis of RCC is unclear. The aim of the present study was to investigate the function of miR-27a and identify its possible target genes in RCC cells. In the present study, cell proliferation, migration and invasion and the percentage of apoptotic cells were detected by methylthiazol tetrazolium assays, Annexin V analysis, wound-healing assays and Transwell invasion assays. Western blot analysis was performed to validate the protein expression level and assess whether the epidermal growth factor receptor (EGFR) was a target gene of miR-27a. A tumor xenograft animal model was used to detect the role of miR-27a on RCC cell growth in vivo. The present study demonstrated that miR-27a significantly suppressed human RCC 786-O cell proliferation and induced cell apoptosis. Restoration of miR-27 also resulted in 786-O cell migration and invasion inhibition. Furthermore, upregulated miR-27a attenuated RCC tumor growth in the tumor xenograft animal model. The present results suggested that miR-27a functions as a tumor suppressor in RCC. The western blot analysis assay revealed that EGFR was a novel target of miR-27a. The growth suppression of RCC cells was attributed partly to the downregulation of the cell cycle by ERFR inhibition. The present findings may aid in the understanding of the molecular mechanism of miR-27a in the tumorigenesis of RCC, and may provide novel diagnostic and therapeutic options for RCC.