The role of microRNA-30a and downstream snail1 on the growth and metastasis of melanoma tumor

Growing evidences have indicated microRNAs as modulators of tumor development and aggression. On the other hand, a phenomenon known as epithelial-mesenchymal transition (EMT) that indicates a transient phase from epithelial-like features to mesenchymal phenotype is a key player in tumor progression.  In this study, we aimed to assess the potential impacts of miR-30a-5p as an inhibitor of melanoma progression and metastasis. MiR-30a-5p was transfected into B16-F10 melanoma cells. Then, the B16-F10 cells were injected subcutaneously or intravenously (IV) in to C57BL/6 mice. Then, the mice were euthanized and tumor size, tumor weight, snail1 protein expression and nodules in the lungs were evaluated. The migration of cancerous cells was significantly suppressed in vitro following the ectopic presentation of miR-30a-5p into B16-F10 melanoma cells. Furthermore, the metastatic behavior of the neoplastic cells was further suppressed in a xenograft mouse model of melanoma as observed with limited lung infiltration. We also found that transfected miR-30a-5p into melanoma cells could decrease snail1 and N-cadherin expression. MiR-30a-5p may represent an effective therapeutic target for the management of melanoma and other snail-overexpressing neoplasms.