OncoTargets and Therapy (Apr 2018)
MicroRNA-328 inhibits migration and epithelial–mesenchymal transition by targeting CD44 in nasopharyngeal carcinoma cells
Abstract
Chien-Hung Lin,1,2 Ming-Chang Chiang,3 Yann-Jang Chen1,4,5 1Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan; 2Department of Pediatrics, Zhongxing Branch, Taipei City Hospital, Taipei, Taiwan; 3Department of Life Science, College of Science and Engineering, Fu Jen Catholic University, New Taipei City, Taiwan; 4Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan; 5Department of Pediatrics, Renai Branch, Taipei City Hospital, Taipei, Taiwan Background: MicroRNAs (miRNAs) play crucial roles in various types of cancers, particularly in tumor development, migration, and progression. Dysregulation of miR-328 was reported to occur in some types of human malignancies, however, the role of miR-328 in nasopharyngeal carcinoma (NPC) and its potential involvement in metastasis remain undetermined. Methods: The invasion capacity of NPC sphere-forming cells was evaluated by in vitro cell migration assays. Differential miRNAs expression was examined in NPC sphere-forming cells compared to parental monolayer cells using miRNA array analysis. The role of miR-328 in regulating NPC cells migratory properties was analyzed after miR-328 mimics transfection. The expression of E-cadherin and CD44 was analyzed by flow cytometry. CD44 was examined as a target of miR-328 through luciferase reporter assays and Western blotting. Results: Here, we report that NPC TW01 and TW06 sphere-forming cells exhibited increased migratory ability in comparison with parental monolayer cells. Sphere-forming cells had significantly lower levels of miR-328, as observed using miRNA arrays and confirmed through real-time polymerase chain reaction. Overexpression of miR-328 induced by transfection with synthetic miR-328 mimics decreased the migration of NPC sphere-forming cells. The inhibitory effects were associated with increased expression of E-cadherin and the downregulated expression of mesenchymal markers such as N-cadherin, Snail, and vimentin. Moreover, our results demonstrated that miR-328 suppressed NPC cell migration and inhibited the epithelial–mesenchymal transition process directly through a binding site on the CD44 3′ untranslated region. Conclusion: miR-328, a previously unrecognized miRNA, may serve as a potential prognostic marker and therapeutic target for NPC. Keywords: miR-328, EMT, CD44, NPC, cancer cell migration
