title: Involvement of hepatoma-derived growth factor in the growth inhibition of hepatocellular carcinoma cells by vitamin K(2).
abstract: BACKGROUND
  Vitamin K(2) has been reported to suppress the growth of human hepatocellular carcinoma (HCC) in vitro and hepatocarcinogenesis in hepatitis C virus (HCV)-related cirrhosis in vivo. Hepatoma-derived growth factor (HDGF) is a unique nuclear targeting growth factor that is highly expressed in HCC cells and is a possible prognostic factor for patients with HCC. We investigated the regulation of HDGF expression by vitamin K(2).
  
  
  METHODS
  Three HCC-derived cell lines, HepG2, HuH-7, and SK-Hep-1, were used. Cell number was determined with the MTT assay. The expression levels of HDGF mRNA and protein were measured by the real-time reverse transcriptase-polymerase chain reaction (PCR) method and ELISA and Western blot analysis, respectively. The HDGF promoter activity was measured by a dual luciferase-reporter assay.
  
  
  RESULTS
  Vitamin K(2) suppressed the growth of the three HCC cell lines in a dose-dependent manner. Vitamin K(2) significantly suppressed the expression of the HDGF protein and mRNA in three cell lines. By a luciferase assay, vitamin K(2) significantly suppressed the promoter activity of the HDGF protein. Based on some luciferase-reporter plasmids containing truncated promoter regions, the possible responsive site of vitamin K(2) seems to reside in the region -1 to -150 bp of the HDGF gene.
  
  
  CONCLUSIONS
  These findings suggested that regulation of the HDGF gene expression is one of the crucial mechanisms of vitamin K(2)-induced cell growth suppression for HCC.
authors.affiliation: Division of Hepatobiliary and Pancreatic Medicine, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo, 663-8501, Japan.
authors.forename: Teruhisa
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Hideji
authors.initials: H
authors.lastname: Nakamura
authors.forename: Weidong
authors.initials: W
authors.lastname: Liu
authors.forename: Ke
authors.initials: K
authors.lastname: Cao
authors.forename: Shohei
authors.initials: S
authors.lastname: Yoshikawa
authors.forename: Hirayuki
authors.initials: H
authors.lastname: Enomoto
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Iwata
authors.forename: Noritoshi
authors.initials: N
authors.lastname: Koh
authors.forename: Masaki
authors.initials: M
authors.lastname: Saito
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Imanishi
authors.forename: Soji
authors.initials: S
authors.lastname: Shimomura
authors.forename: Hiroko
authors.initials: H
authors.lastname: Iijima
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Hada
authors.forename: Shuhei
authors.initials: S
authors.lastname: Nishiguchi
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000494:pharmacology*; D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy / Q000378:metabolism; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D017930:Genes, Reporter; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism*; D008113:Liver Neoplasms / Q000188:drug therapy / Q000378:metabolism; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D024482:Vitamin K 2 / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; D036341:Intercellular Signaling Peptides and Proteins; D012333:RNA, Messenger; C051610:hepatoma-derived growth factor; D024482:Vitamin K 2; D008156:Luciferases