miR-942-5p promotes the proliferation and invasion of human melanoma cells by targeting DKK3.

The purpose of this study was to figure out the dysregulation of miR-942-5p in melanoma and its role in melanoma pathogenesis. Quantitative real-time PCR (qRT-PCR) assay was used to determine the change of RNA expression. Protein expression was examined by Western blotting. miRNA target was validated through TargetScan and luciferase assay. Cell migration and invasion were detected by wound healing and transwell assay, respectively. Results of qRT-PCR manifested miR-942-5p were upregulated in melanoma cell. High expression of miR-942-5p in melanoma patients presented a poor prognosis. Upregulation of miR-942-5p accelerated cell proliferation, migration, and invasion in melanoma cells. Cell apoptosis was inhibited by miR-942-5p mimics. Suppression of miR-942-5p by its inhibitor showed the opposite effects in melanoma cells. TargetScan and luciferase assay showed that miR-942-5p directly targeted to the 3′-untranslated region (3′-UTR) of DKK3. Overexpression of DKK3 inhibited GSK-3β phosphorylation and reduced the expression of β-catenin in both cytoplasm and nucleus, which were induced by miR-942-5p mimics leading to the activation of Wnt/β-catenin pathway. Upregulation of miR-942-5p was observed in melanoma cells and tissues and significantly associated with a poor prognosis. Though targeting 3′-UTR of DKK3, miR-942-5p could activate Wnt/β-catenin pathway, resulting in melanoma cell proliferation, migration, and invasion, which promoted the development of melanoma. These results showed that miR-942-5p might be a diagnosis and prognosis biomarker in melanoma. [ABSTRACT FROM AUTHOR]