title: GNAI1 Suppresses Tumor Cell Migration and Invasion and is Post-Transcriptionally Regulated by Mir-320a/c/d in Hepatocellular Carcinoma.
abstract: OBJECTIVE
  To explore the role and regulation of guanine nucleotide-binding protein G(i), α-1 subunit (GNAI1) in hepatocellular carcinoma (HCC).
  
  
  METHODS
  Expression of GNAI1 in HCC samples was determined by qRT-PCR and immunohistochemical (IHC) staining. Huh-7 and SNU-387 cells stably expressing GNAI1 were established by the infection of lentivirus transducing unit containing GNAI1. siRNA against GNAI1 was transfected into SMMC-7721 cells to knock down the GNAI1 expression in HCC cells. Mir-320a/c/d mimics were transfected into SMMC-7721 and SK-Hep-1 cells and the expression of GNAI1 was determined by Western blot. The migration and invasion of Huh-7, SNU-387, SK-Hep-1 and SMMC-7721 cells were investigated by Transwell assays.
  
  
  RESULTS
  The GNAI1 protein was significantly downregulated in HCC samples without changes in its mRNA levels. GNAI1 could inhibit the migration and invasion of HCC cells in vitro. Further investigations indicated that GNAI1 was a target of miR-320a/c/d in HCC cells. Transwell assays demonstrated that these microRNAs could promote the migratory ability and invasivesess of HCC cells in vitro.
  
  
  CONCLUSIONS
  GNAI1 is downregulated in HCC and inhibits the migration and invasion of HCC cells. This study is the first to investigate the role of GNAI1 in cancer. Regulation of GNAI1 by miR-320a/c/d indicates new therapeutic avenues for targeting HCC metastasis.
authors.affiliation: State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032, China ; State Key Laboratory for Diagnosis and Treatment for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Yao
authors.forename: Lin-Hui
authors.initials: LH
authors.lastname: Liang
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jie
authors.initials: J
authors.lastname: Ding
authors.forename: Qi
authors.initials: Q
authors.lastname: Tian
authors.forename: Jin-Jun
authors.initials: JJ
authors.lastname: Li
authors.forename: Xiang-Huo
authors.initials: XH
authors.lastname: He
keywords: GNAI1; HCC; invasion; miR-320; migration