CDKN2C and melanoma: Both hsa-miR-21-5p and hsa-miR-221-3p are onco-miRNAs, and hsa-miR-21-5p was found upregulated in melanoma tissues, and in vitro experiments have established its role in cell cycle regulation by targeting the cyclin-dependent kinase inhibitor 2C (CDKN2C) (9).