title: [EGF/PI3K signaling pathway regulates the expression of osteopontin in liver cancer HepG2 cells].
abstract: OBJECTIVE
  To investigate the effect of epidermal growth factor (EGF) on the expression of osteopontin (OPN) in liver cancer HepG2 cells.
  
  
  METHODS
  Human liver caner cells of HepG2 line were cultured in medium without bovine serum. EGF was added. Another cells were pretreated with specific phosphatidylinositol 3 (PI3) inhibitor Wortmannin and then added with EGF. HepG2 cell were collected. RNase prote4ction assay and Western blotting were used to examine the expression of OPN in the HepG2 cells.
  
  
  RESULTS
  HepG2 cells cultured in the bovine serum free medium expressed very low level of OPN. EGF increased the expression of OPN mRNA and protein in a dose- and time-dependent manners. Pretreatment of Wortmannin significantly reduced the EGF-induced OPN expression.
  
  
  CONCLUSIONS
  EGF increases the OPN expression, possibly through PI3 signaling pathway. It is possible to block the synthesis of OPN through manipulating several target genes, thus inhibiting the metastasis of liver cancer.
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China.
authors.forename: Guo-xin
authors.initials: GX
authors.lastname: Zhang
authors.forename: Zhi-quan
authors.initials: ZQ
authors.lastname: Zhao
authors.forename: Xiu-wen
authors.initials: XW
authors.lastname: Lin
mesh_terms: D000730:Androstadienes / Q000494:pharmacology; D045744:Cell Line, Tumor; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism*; D053495:Osteopontin; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology*; D012795:Sialoglycoproteins / Q000235:genetics*; D015398:Signal Transduction / Q000502:physiology*; D000077191:Wortmannin
chemical_list: D000730:Androstadienes; C506895:SPP1 protein, human; D012795:Sialoglycoproteins; D053495:Osteopontin; D004815:Epidermal Growth Factor; D019869:Phosphatidylinositol 3-Kinases; D000077191:Wortmannin