title: Tie2 vascular endothelial receptor expression and function in hepatocellular carcinoma.
abstract: Hepatocellular carcinoma (HCC) is generally characterized as a hypervascular tumor of rapid growth. We have previously reported that angiopoietin (Ang), a ligand for Tie2 vascular endothelial-specific receptor tyrosine kinase, may play a role in the progression of human HCC (J Clin Invest 1999;103:341-345) and matrix proteinase expression (Cancer Res 2001;61:2145-2153). However, the role of Tie2 receptor in hepatic oncogenesis is unknown. The Tie2 receptor protein was overexpressed in the neovascular endothelium of 31 of 39 (80%) human HCC tumors by immunohistochemical analysis with significant correlation to cell dedifferentiation and tumor size (P <.05). In vitro expression of a dominant-negative construct, containing a soluble Tie2 ectodomain (sTie2), led to Ang protein interaction, inhibition of endogenous Tie2 phosphorylation in vascular endothelial cells and matrix metalloproteinase 9 (MMP-9) suppression. In conclusion, tumorigenicity with neovascularization was suppressed by in vivo gene transfer and sTie2 expression in a murine HCC model, suggesting a possible role for Tie2 expression in the induction of HCC neovascularization and disease progression. Inhibition of the Ang/Tie2 signal transduction cascade is a promising approach for tumor treatment.
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, and Station for Collaborative Research, Kyushu University, Fukuoka, Japan. shinjit@surg2.med.kyushu-u.ac.jp
authors.forename: Shinji
authors.initials: S
authors.lastname: Tanaka
authors.forename: Keishi
authors.initials: K
authors.lastname: Sugimachi
authors.forename: Yo-ichi
authors.initials: Y
authors.lastname: Yamashita Yi
authors.forename: Takefumi
authors.initials: T
authors.lastname: Ohga
authors.forename: Ken
authors.initials: K
authors.lastname: Shirabe
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Shimada
authors.forename: Jack R
authors.initials: JR
authors.lastname: Wands
authors.forename: Keizo
authors.initials: K
authors.lastname: Sugimachi
mesh_terms: D042683:Angiopoietin-1; D042702:Angiopoietin-2; D006528:Carcinoma, Hepatocellular / Q000378:metabolism* / Q000473:pathology; D002454:Cell Differentiation / Q000502:physiology; D002478:Cells, Cultured; D018274:Electroporation; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism; D004789:Enzyme Activation; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D011506:Proteins / Q000378:metabolism; D011518:Proto-Oncogene Proteins; D042787:Receptor, TIE-2
chemical_list: C467630:ANGPT1 protein, human; D042683:Angiopoietin-1; D042702:Angiopoietin-2; C105373:MEN1 protein, human; D008562:Membrane Glycoproteins; D009363:Neoplasm Proteins; D011506:Proteins; D011518:Proto-Oncogene Proteins; D042787:Receptor, TIE-2