title: MiR-145 inhibits oral squamous cell carcinoma (OSCC) cell growth by targeting c-Myc and Cdk6.
abstract: BACKGROUND
  MicroRNAs (miRNAs) are a large group of negative gene regulators that potentially play a critical role in tumorigenesis. Increasing evidences indicate that miR-145 acts a tumor suppressor in numerous human cancers. However, its role in oral carcinogenesis remains poorly defined. The aim of this study is to determine expression levels of miR-145 in oral squamous cell carcinomas (OSCCs) and normal mucosa tissues, and explore its biological functions in OSCCs.
  
  
  METHODS
  Reverse transcription quantitative real-time PCR (RT-qPCR) assay was used to evaluate expression levels of miR-145. The biological functions of miR-145 were determined by cell proliferation and colony formation, cell cycle and apoptosis, as well as cell invasion assay.
  
  
  RESULTS
  MiR-145 was frequently down-regulated in OSCCs compared with normal mucosa tissues. Restoring miR-145 expression in OSCC cells dramatically suppressed cell proliferation and colony formation, and induced G1 phase arrest and cell apoptosis. Importantly, our data showed that miR-145 downregulated the expression of c-Myc and Cdk6, which have previously been identified as two direct targets of miR-145.
  
  
  CONCLUSIONS
  Our data suggest that miR-145 exerts its tumor suppressor function by targeting c-Myc and Cdk6, leading to the inhibition of OSCC cell growth. MiR-145 rescue may thus be a rational for diagnostic and therapeutic applications in OSCC.
authors.affiliation: Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong, Xi'an 710061, the People's Republic of China. mjji0409@163.com.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Shao
authors.forename: Yiping
authors.initials: Y
authors.lastname: Qu
authors.forename: Siwen
authors.initials: S
authors.lastname: Dang
authors.forename: Bowen
authors.initials: B
authors.lastname: Yao
authors.forename: Meiju
authors.initials: M
authors.lastname: Ji