Minimal active domain and mechanism of action of the angiogenesis inhibitor histidine-rich glycoprotein.
Histidine-rich glycoprotein (HRGP) is an abundant heparin-binding plasma protein that efficiently arrests growth and vascularization of mouse tumor models. We have shown that the antiangiogenic effect of HRGP is dependent on its histidine/proline-rich domain, which needs to be released from the mother protein to exert its effects. Here we identify a 35-amino-acid peptide, HRGP330, derived from the histidine/proline-rich domain as endowed with antiangiogenic properties in vitro and in vivo. The mechanism of action of HRGP330 involves subversion of focal adhesion function by disruption of integrin-linked kinase (ILK) and focal adhesion kinase (FAK) functions, inhibition of vascular endothelial growth factor (VEGF)-induced tyrosine phosphorylation of the FAK substrate alpha-actinin, and, as a consequence, an arrest in endothelial cell motility. The disturbed focal adhesion function is reflected in the ability of HRGP as well as of HRGP330 to prevent endothelial cell adhesion to vitronectin in a manner involving alpha(v)beta3 integrin. In conclusion, HRGP330, which we define as the minimal antiangiogenic domain of HRGP, exerts its effects through signal transduction targeting focal adhesions, thereby interrupting VEGF-induced endothelial cell motility.
Rudbeck Laboratory, Department of Genetics and Pathology, Uppsala University, Uppsala, Sweden.
Johan
J
Dixelius
Anna-Karin
AK
Olsson
Asa
A
Thulin
Chunsik
C
Lee
Irja
I
Johansson
Lena
L
Claesson-Welsh
D000185:Actinin / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects*; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000378:metabolism; D039302:Integrin alphaVbeta3 / Q000378:metabolism; D008969:Molecular Sequence Data; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D051419:Paxillin / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D010446:Peptide Fragments / Q000737:chemistry / Q000494:pharmacology*; D010766:Phosphorylation / Q000187:drug effects; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry / Q000494:pharmacology*; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000494:pharmacology; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism; D000099053:Histidine-Rich Glycoprotein; D000099200:Scaffold Protein ILK
D000185:Actinin; D051416:Focal Adhesion Protein-Tyrosine Kinases; D039302:Integrin alphaVbeta3; D051419:Paxillin; D010446:Peptide Fragments; D017346:Protein Serine-Threonine Kinases; D011506:Proteins; D042461:Vascular Endothelial Growth Factor A; D040301:Vascular Endothelial Growth Factor Receptor-2; D000099053:Histidine-Rich Glycoprotein; D000099200:Scaffold Protein ILK