Vascular endothelial growth factor A (VEGF-A) induces endothelial and cancer cell migration through direct binding to integrin 91: identification of a specific 91 binding site.

Authors:
Oommen S, Gupta SK, Vlahakis NE.
In:
Source: J Biol Chem
Publication Date: (2011)
Issue: 286(2): 1083-92
Research Area:
Basic Research
Cells used in publication:
Endothelial, umbilical vein, human (HUVEC)
Species: human
Tissue Origin: vein
Endothelial, MV lung, human (HMVEC-L)
Species: human
Tissue Origin: lung
Abstract
Integrin a9ß1 mediates accelerated cell adhesion and migration through interactions with a number of diverse extracellular ligands. We have shown previously that it directly binds the vascular endothelial growth factors (VEGF) A, C, and D and contributes to VEGF-induced angiogenesis and lymphangiogenesis. Until now, the a9ß1 binding site in VEGF has not been identified. Here, we report that the three-amino acid sequence, EYP, encoded by exon 3 of VEGF-A is essential for binding of VEGF to integrin a9ß1 and induces adhesion and migration of endothelial and cancer cells. EYP is specific for a9ß1 binding and neither requires nor activates VEGFR-2, the cognate receptor for VEGF-A. Following binding to EYP, integrin a9ß1 transduces cell migration through direct activation of the integrin signaling intermediates Src and focal adhesion kinase. This interaction is biologically important because it mediates in vitro endothelial cell tube formation, wound healing, and cancer cell invasion. These novel findings identify EYP as a potential site for directed pharmacotherapy.