Factor XII stimulates ERK1/2 and Akt through uPAR, integrins, and the EGFR to initiate angiogenesis.
Factor XII (FXII) and high molecular weight kininogen (HK) mutually block each other's binding to the urokinase plasminogen activator receptor (uPAR). We investigated if FXII stimulates cells by interacting with uPAR. FXII (3-62nM) with 0.05mM Zn(2+) induces extracellular signal-related kinase 1/2 (ERK1/2; mitogen-activated protein kinase 44 [MAPK44] and MAPK42) and Akt (Ser473) phosphorylation in endothelial cells. FXII-induced phosphorylation of ERK1/2 or Akt is a zymogen activity, not an enzymatic event. ERK1/2 or Akt phosphorylation is blocked upstream by PD98059 or Wortmannin or LY294002, respectively. An uPAR signaling region for FXII is on domain 2 adjacent to uPAR's integrin binding site. Cleaved HK or peptides from HK's domain 5 blocks FXII-induced ERK1/2 and Akt phosphorylation. A beta(1) integrin peptide that binds uPAR, antibody 6S6 to beta(1) integrin, or the epidermal growth factor receptor (EGFR) inhibitor AG1478 blocks FXII-induced phosphorylation of ERK1/2 and Akt. FXII induces endothelial cell proliferation and 5-bromo-2'deoxy-uridine incorporation. FXII stimulates aortic sprouting in normal but not uPAR-deficient mouse aorta. FXII produces angiogenesis in matrigel plugs in normal but not uPAR-deficient mice. FXII knockout mice have reduced constitutive and wound-induced blood vessel number. In sum, FXII initiates signaling mediated by uPAR, beta(1) integrin, and the EGFR to induce human umbilical vein endothelial cell proliferation, growth, and angiogenesis.
Division of Hematology and Oncology, Department of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA.
Gretchen A
GA
LaRusch
Fakhri
F
Mahdi
Zia
Z
Shariat-Madar
Gregory
G
Adams
Robert G
RG
Sitrin
Wan Ming
WM
Zhang
Keith R
KR
McCrae
Alvin H
AH
Schmaier
D000818:Animals; D001013:Aorta, Thoracic / Q000166:cytology / Q000378:metabolism; D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D066246:ErbB Receptors / Q000378:metabolism*; D005174:Factor XII / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D016023:Integrins / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors / Q000378:metabolism; D018919:Neovascularization, Physiologic / Q000187:drug effects / Q000502:physiology*; D010766:Phosphorylation / Q000187:drug effects / Q000502:physiology; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D055293:Receptors, Urokinase Plasminogen Activator / Q000378:metabolism*; D014471:Umbilical Veins / Q000166:cytology
D004791:Enzyme Inhibitors; D016023:Integrins; D055293:Receptors, Urokinase Plasminogen Activator; D005174:Factor XII; D066246:ErbB Receptors; D051057:Proto-Oncogene Proteins c-akt; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3