RNA Extraction and Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR)

Total RNA was extracted from RCC tissues and cells using TRIzol reagent (Thermo Fisher Scientific, Waltham, MA, USA) following the manufacturer’s protocol. The RNA quality and quantity were verified with a NanoDrop 1000 (Thermo Fisher Scientific). Then, the TaqMan MicroRNA Reverse Transcription Kit (Thermo Fisher Scientific) was used to synthesize cDNA from total RNA following the manufacturer’s instructions. Subsequently, qRT-PCR was performed to measure miR-592 expression using a TaqMan MicroRNA Assay kit (Thermo Fisher Scientific) on an ABI 7500 PCR System. The relative expression levels of miR-592 were calculated using 2^−ΔΔCt methods and normalized to those of U6.