MiR-338-5p promotes the growth and metastasis of malignant melanoma cells via targeting CD82.

Melanoma has been a severe threat to human health, microRNAs play vital roles in the oncogenesis and progression of cancers. In this report, the roles and mechanism of miR-338-5p were investigated in the development of melanoma. A total of 46 melanoma samples and 25 normal nevi samples were collected. Real time reverse transcriptase polymerase chain reaction and Western blot were used to detect the expression of mRNA and protein. Cell proliferation, migration and invasion were detected by CCK-8 assay, wound healing assay and transwell assay. A luciferase reporter assay was performed to identify whether miR-338-5p targeted the 3'-UTR of CD82 mRNA. Nude mice experiment was applied to determine the effect of miR-338-5p on melanoma development. miR-338-5p expression was upregulated in melanoma tissues and cell lines. MiR-338-5p level in tumor tissues was correlated with tumor stage, metastasis and patients survival rate. High miR-338-5p expression promoted the proliferation and metastasis of A375 cells. The inhibition of miR-338-5p suppressed growth and metastasis of A375 cells. CD82 mRNA was identified as a direct target mRNA of miR-338-5p. MiR-338-5p could regulate the expression of CD82 protein. MiR-338-5p mimics improved the growth and metastasis of A375 cells transfected with CD82 vector, while inhibition of miR-338-5p attenuated the pro-tumor function of si-CD82 in A375 cells. Lastly, the high level of miR-338-5p promoted xenograft tumor growth in vivo. The oncogenic mechanisms of miR-338-5p are elucidated on the procession of melanoma. Downregulation of miR-338-5p maybe a vital therapeutic strategy against melanoma.