MicroRNA-338 Inhibits Migration And Proliferation By Targeting Hypoxia-induced Factor 1α In Nasopharyngeal Carcinoma

Objective: The aim of the present study was to investigate the potential role of miR-338 in the development and progression of NPC under hypoxia microenvironment.Methods:q RT-QPCR analysis were used to detect the expression of microRNA338 in NPC tissues and cells compared to the normal control.Luciferase reporter assaywere used to determine the relationship between mi R-338 and HIF1-α.Wound healing assay,migration assays were used to detect the metastasis ablity of NPC cells transfected with mi R-338 mimics or inhibitor.Flow cytometry and Cell viability assay(Cell Counting kit-8)were used to detect the proliferation of NPC cells.Results: Compared with normal samples,our data showed that miR-338 were downregulated in NPC tissues and cells.The luciferase assay demonstrated that HIF-1αwas a direct target of miR-338.We also found that miR-338 regulated the expression levels of HIF-1α,respectively.Overexpression of miR-338 in NPC cells significantly inhibited cell proliferation,and migration.Conversely,mi R-338 knockdown in cells with lower endogenous expression levels significantly reduced antitumor behavior.Furthermore,enforced expression of miR-338 led to a decline in ERK phosphorylation as well as inhibited the hypoxia induced epithelial to mesenchymal transition.Cells RT-qPCR)analysis pre-transfected with miR-338 can overcome hypoxia mediated cisplatin resistance.Conclusions: We found that miR-338 directly targeted HIF-1α,and we provide insight into NPC initiation and progression,possibly representing a novel therapeutic target.