MiR-142-3p Suppresses SOCS6 Expression and Promotes Cell Proliferation in Nasopharyngeal Carcinoma.

BACKGROUND/AIMS An increasing number of studies show that microRNAs (miRNAs) play crucial roles in nasopharyngeal carcinoma (NPC) tumorigenesis. The aim of our study was to investigate the biological roles and mechanisms of miR-142-3p in NPC. METHODS miR- 142-3p expression was examined in NPC specimens and nasopharyngitis biopsy samples by quantitative real-time PCR. The biological functions of miR-142-3p were studied using a series of in vitro and in vivo approaches. RESULTS miR-142-3p is over-expressed in NPC tissues and cell lines. Knockdown of miR-142-3p significantly inhibited cell proliferation and cell cycle progression in vitro, and suppressed tumor growth in a mouse model. Suppressor of cytokine signaling 6 (SOCS6) was identified as a direct target of miR-142-3p, and miR- 142-3p down-regulated the expression of SOCS6 by directly binding to its 3′untranslated region (UTR). Knockdown of SOCS6 abrogated the effects of miR-142-3p down-regulation. CONCLUSION These findings indicate that miR-142-3p regulates NPC development by down-regulating SOCS6 expression and suggest that modulation of miR-142-3p expression could be a therapeutic strategy for NPC.