Mirna‐424‐5p suppresses proliferation, migration, and invasion of clear cell renal cell carcinoma and attenuates expression of o‐glcnac‐transferase

Abstract

MicroRNAs (miRNAs) are non‐coding post‐transcriptional regulators of gene expression that are dysregulated in clear cell renal cell carcinoma (ccRCC) and play an important role in tumor progression. Our prior work identified a subset of miRNAs in pT1 ccRCC tumors, including miR‐ 424‐5p, that are associated with an aggressive phenotype. We investigate the impact of this dysreg-ulated miRNA and its protein target O‐GlcNAc‐transferase (OGT) to better understand the mechanisms behind aggressive stage I ccRCC. The ccRCC cell lines 786‐O and Caki‐1 were used to assess the impact of miR‐424‐5p and OGT. Cells were transfected with pre‐miR‐424‐5p, a lentiviral anti‐ OGT shRNA, or were treated with the demethylating agent 5‐Aza‐2′‐deoxycytidine. Cell proliferation was measured via MT cell viability assay. Cell migration and invasion were analyzed using Transwell assays. The expression of miR‐424‐5p was determined through qRT‐PCR, while OGT protein expression was evaluated through Western blotting. The interaction between miR‐424‐5p and OGT was confirmed via luciferase reporter assay. The transfection of ccRCC cells with pre‐miR‐ 424‐5p or anti‐OGT shRNA significantly inhibited cell proliferation, migration, and OGT expres-sion, while miR‐424‐5p also attenuated cell invasion. Addition of the demethylating agent significantly reduced cell proliferation, migration, invasion, and OGT expression, while significantly increasing the expression of miR‐424‐5p. Altogether, these findings suggest that epigenetic downreg-ulation of miR‐424‐5p, which in turn augments OGT expression, contributes to the creation of aggressive forms of stage I ccRCC.