High miR-122 expression promotes malignant phenotypes in ccRCC by targeting occludin

• Published in: International journal of oncology Vol. 51; no. 1; pp. 289 - 297
• Main Authors: Jingushi, Kentaro, Kashiwagi, Yuri, Ueda, Yuko, Kitae, Kaori, Hase, Hiroaki, Nakata, Wataru, Fujita, Kazutoshi, Uemura, Motohide, Nonomura, Norio, Tsujikawa, Kazutake
• Format: Journal Article
• Language: English
• Published: Greece Spandidos Publications 01.07.2017; Spandidos Publications UK Ltd
• Subjects: Adult; Aged; Aged, 80 and over; Apoptosis; Binding sites; Biomarkers, Tumor - genetics; Biomarkers, Tumor - metabolism; Breast cancer; Carcinoma, Renal cell; Carcinoma, Renal Cell - genetics; Carcinoma, Renal Cell - metabolism; Carcinoma, Renal Cell - pathology; Cell Proliferation; Female; Gene expression; Gene Expression Regulation, Neoplastic; Genetic aspects; Humans; Immunoglobulins; Kidney cancer; Kidney Neoplasms - genetics; Kidney Neoplasms - metabolism; Kidney Neoplasms - pathology; Liver cancer; Male; Medical prognosis; Metastasis; MicroRNA; MicroRNAs; MicroRNAs - genetics; Middle Aged; Motility; Occludin - genetics; Occludin - metabolism; Phenotype; Phosphorylation; Prognosis; Studies; Thermal cycling; Tumor Cells, Cultured; Wound healing; United States > US
• ISSN: 1019-6439; 1791-2423
• DOI: 10.3892/ijo.2017.4016

Renal cell carcinoma (RCC) is the most common neoplasm of the adult kidney, and clear cell RCC (ccRCC) represents its most common histological subtype. Although several studies have reported high expression of miR-122 in ccRCC, its physiological role remains unclear. To clarify the role of miR-122 in ccRCC, we compared miR-122 expression levels in non-cancerous tissue and ccRCC. Significant upregulation of miR-122 was observed in ccRCC specimens. Moreover, ccRCC patients with high miR-122 expression showed poor progression-free survival compared to those with low miR-122 expression. Overexpression of miR-122 using an miRNA mimic promoted proliferation, migration, and invasion activities of ccRCC cells. miR-122 directly targets occludin, a known component of tight junctions. Occludin knockdown promoted the cell migration activity but not proliferation or invasion activities of ccRCC cells. In human clinical specimens, miR-122 expression inversely correlated with occludin protein expression. These findings show that miR-122 is an oncomiR in ccRCC.