Unknown,Transcriptomics,Genomics,Proteomics

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MicroRNA-7-5p inhibits melanoma cell proliferation and metastasis by suppressing RelA

ABSTRACT: microRNA-7-5p (miR-7-5p) is an established tumor suppressor in multiple cancer types and inhibits growth and invasion by suppressing expression and activity of the epidermal growth factor receptor (EGFR) signaling pathway. While melanoma is not typically driven by EGFR signaling, expression of miR-7-5p is reduced in metastatic tumors compared to primary melanoma. Here, we investigated the biological and clinical significance of miR-7-5p in melanoma. Our results showed that augmenting miR-7-5p expression in vitro markedly reduced tumor cell viability, colony formation and induced cell cycle arrest. Furthermore, ectopic expression of miR-7-5p reduced migration and invasion of melanoma cells in vitro and reduced melanoma lung colonizationmetastasis in vivo. To investigate the mechanism underlying this effect, we used cDNA microarray analysis to identify a subset of putative miR-7-5p target genes associated with melanoma and metastasis. Of these, we confirmed nuclear factor kappa B (NF-ÎºB) subunit RelA, as a novel direct target of miR-7-5p in melanoma cells, such that miR-7-5p suppresses NF-ÎºB activity to decrease expression of canonical NF-ÎºB target genes, including IL-1a, IL-6 and IL-8. Importantly, the effects of miR-7-5p on melanoma cell growth, cell cycle, migration and invasion were recapitulated by RelA knockdown. Finally, analysis of gene array datasets from multiple melanoma patient cohorts revealed an association between elevated RelA expression and poor survival, further emphasizing the clinical significance of RelA and its downstream signaling effectors.. Taken together, our data suggest that miR-7-5p replacement therapy might have clinical utility in melanoma to inhibit the metastatic process, in part through its inactivation of RelA/NF-kB signaling. Total RNA was extracted from WM266-4 cells transfected with miR-NC or miR-7-5p precursor molecules (30 nM) for 24 h, using Qiazol reagent (Qiagen).

ORGANISM(S): Homo sapiens

SUBMITTER: Patrick Candy

PROVIDER: E-GEOD-77196 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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MicroRNA-7-5p inhibits melanoma cell proliferation and metastasis by suppressing RelA

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