LncRNA CDKN2B-AS1/miR-141/cyclin D network regulates tumor progression and metastasis of renal cell carcinoma.

ABSTRACT

The molecular heterogeneity of renal cell carcinoma (RCC) complicates the therapeutic interventions for advanced metastatic disease and thus its management remains a significant challenge. This study investigates the role of the lncRNA CDKN2B-AS1 and miR-141-3p interactions in the progression and metastasis of kidney cancer. Human renal cancer cell lines (ACHN and Caki1), normal RPTEC cells, tissue cohorts, and a series of in vitro assays and in vivo mouse model were used for this study. An overexpression of CDKN2B-AS1 was observed in RCC compared to normal samples in TCGA and our in-house SFVAMC tissue cohorts. Reciprocally, we observed reduced expression of miR-141 in RCC compared to normal in the same cohorts. CDKN2B-AS1 shares regulatory miR-141 binding sites with CCND1 and CCND2 genes. Direct interactions of CDKN2B-AS1/miR-141/Cyclin D1-D2 were confirmed by RNA immunoprecipitation and luciferase reporter assays indicating that CDKN2B-AS1/miR-141/Cyclin D1-D2 acts as a ceRNA network in RCC. Functionally, attenuation of CDKN2B-AS1 and/or overexpression of miR-141 inhibited proliferation, clonogenicity, migration/invasion, induced apoptosis in vitro and suppressed tumor growth in xenograft mouse model. Further, overexpression of CDKN2B-AS1 is positively correlated with poor overall survival of RCC patients. Expression of miR-141 also robustly discriminated malignant from non-malignant tissues and its inhibition in normal RPTEC cells induced pro-cancerous characteristics. CDKN2B-AS1 attenuation or miR-141 overexpression decreased CCND1/CCND2 expression, resulting in reduced RAC1/pPXN that are involved in migration, invasion and epithelial-mesenchymal transition. This study, for the first time, deciphered the role of CDKN2B-AS1/miR-141/Cyclin D axis in RCC and highlights this network as a promising therapeutic target for the regulation of EMT driven metastasis in RCC.