Heparin affin regulatory peptide binds to vascular endothelial growth factor (VEGF) and inhibits VEGF-induced angiogenesis

Oncogene. 2004 Mar 4;23(9):1745-53. doi: 10.1038/sj.onc.1206879.


Heparin affin regulatory peptide (HARP) is an heparin-binding molecule involved in the regulation of cell proliferation and differentiation. Here, we report that HARP inhibited the biological activity induced by the 165-amino-acid form of vascular endothelial growth factor (VEGF165) on human umbilical vein endothelial cells. Endothelial-cell proliferation induced by VEGF165 showed about 50% inhibition in the presence of HARP in a concentration of 3 nM. In similar range of concentrations, HARP blocked tube formation induced by VEGF165 in three-dimensional angiogenesis assay. In vivo studies showed that HARP inhibited the VEGF165-induced Matrigel trade mark infiltration of endothelial cells. We then investigated the mechanisms of this inhibition and shown that HARP inhibited the binding of 125I-VEGF165 to the VEGF receptors of endothelial cells. Additional studies using VEGF soluble receptors indicated that binding of 125I-VEGF165 to kinase insert domain-containing receptor and neuropilin receptor was inhibited by HARP, but conversely the binding of 125I-VEGF165 to fms-like tyrosine kinase I receptor was unaffected. A competitive affinity-binding assay demonstrated that HARP interacted directly with VEGF165 with a dissociation coefficient of 1.38 nM. Binding assay using deletion mutants of HARP revealed that the thrombospondin type-1 repeats domains were involved in this interaction. These data demonstrate for the first time that the angiogenic factor HARP can also negatively regulates the angiogenic activity of VEGF165.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Carrier Proteins / chemistry
  • Carrier Proteins / metabolism*
  • Carrier Proteins / pharmacology*
  • Cell Differentiation / drug effects
  • Cell Division / drug effects
  • Cell Movement / drug effects
  • Cells, Cultured
  • Collagen
  • Cytokines / chemistry
  • Cytokines / metabolism*
  • Cytokines / pharmacology*
  • Drug Combinations
  • Endothelial Cells / cytology
  • Endothelial Cells / drug effects
  • Heparin / pharmacology
  • Humans
  • Laminin
  • Neovascularization, Physiologic / drug effects*
  • Protein Binding / drug effects
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Proteoglycans
  • Receptors, Vascular Endothelial Growth Factor / antagonists & inhibitors
  • Receptors, Vascular Endothelial Growth Factor / metabolism
  • Vascular Endothelial Growth Factor A / antagonists & inhibitors*
  • Vascular Endothelial Growth Factor A / metabolism*
  • Vascular Endothelial Growth Factor A / pharmacology


  • Carrier Proteins
  • Cytokines
  • Drug Combinations
  • Laminin
  • Proteoglycans
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • matrigel
  • pleiotrophin
  • Heparin
  • Collagen
  • Receptors, Vascular Endothelial Growth Factor