MicroRNA-20a-3p and microRNA-20a-5p exhibit anti-proliferative activities in a melanoma in vitro model

MicroRNAs control numerous cancer-related signaling pathways and play pivotal role in cancer initiation and progression.Recent studies have indicated variable and cancer-specific expression patterns of mi-croRNA-20a (miR-20a), which have been attended by varying and sometimes contrary tumor biological functions.This is the first study regarding to the characterization of miR-20a's functionality in melanoma cells.miR-20a expression was examined by reverse transcriptase and quantitative polymerase chain reaction in an in vitro melanoma model containing HaCat keratinocytes and B16 melanoma cells.For cell growth analysis, miR-20a vectors were cloned and transfected into B16 cells.Cell growth kinetics were performed utilizing a Cell Counter and Analyzer Model TT (Roche Applied Science).The expression of both the 3p and the 5p strand processed from the miR-20a precursor was suppressed in melanoma cells B16 compared to the expression in non-malignant HaCat keratinocytes.Recombinant restoration of miR -20a levels in malignant B16 cells attenuated cellular growth.Our data suggest that miR-20a bears biological functions in melanoma cells and thus represents an anti-oncogenic factor which is suppressed during cancer progression.