Abstract:

Objective To investigate the effect of microRNA-let-7a on apoptosis in melanoma cell line A375 and its mechanism. Methods The expression of microRNA-let-7a was detected in A375 cells and melanocytes by real-time PCR. Then, microRNA-let-7a mimics was transfected into A375 cells followed by the measurement of apoptosis and caspase-3 protein expression by flow cytometry and Western blotting, respectively. Results The expression level of microRNA-let-7a was reduced by 0.462 folds in A375 cells compared with melanocytes. The apoptosis rate was 47.4% in A375 cells transfected with microRNA-let-7a mimics, significantly higher than that in untransfected A375 cells （16.9%）. A significant decline was observed in the expression of caspase-3 protein in A375 cells after transfection. Conclusion microRNA-let-7a can promote the apoptosis and downregulate caspase-3 protein expression, in A375 human malignant melanoma cells.

Key words: microRNA-let-7a, melanoma, apoptosis