MicroRNA-152 Targets Phosphatase and Tensin Homolog to Inhibit Apoptosis and Promote Cell Migration of Nasopharyngeal Carcinoma Cells

BACKGROUND Nasopharyngeal carcinoma (NPC) is a type of head and neck cancer with very high prevalence in southern China. Phosphatase and tensin homolog (PTEN), a tumor suppressor, was reported to be downregulated in NPC patients and correlated with pathological grade and clinical stage of NPC. MATERIAL AND METHODS Luciferase reporter assay, qPCR, and Western blot analysis were used to determine if PTEN is a target of miR-152. The function of miR-152 in cell apoptosis and cell proliferation was examined as well. Tissue samples from NPC patients were also analyzed for PTEN and miR-152 expressions. RESULTS Reporter assay indicated miR-152 targets the 3'UTR of PTEN mRNA to inhibit PTEN expression. Transfection of the NPC-derived cell line with miR-152 mimic confirmed these findings. Overexpression of miRNA-152 inhibits apoptosis induced by Cisplatin in NPC cancer cells in vitro. Moreover, overexpression miR-152 also promotes NPC cancer cell invasion and proliferation. Samples from EBV-negative NPC patients demonstrated the down-regulated level of PTEN may be related with overexpression of miR-152. CONCLUSIONS The miR-152 targets PETN to inhibit cell apoptosis and promote cancer cell proliferation and migration in NPC development.