title: VEGF-integrin interplay controls tumor growth and vascularization.
abstract: Cross-talk between the major angiogenic growth factor, VEGF, and integrin cell adhesion receptors has emerged recently as a critical factor in the regulation of angiogenesis and tumor development. However, the molecular mechanisms and consequences of this intercommunication remain unclear. Here, we define a mechanism whereby integrin alpha v beta3, through activation, clustering, and signaling by means of p66 Shc (Src homology 2 domain containing), regulates the production of VEGF in tumor cells expressing this integrin. Tumors with "activatable" but not "inactive" beta3 integrin secrete high levels of VEGF, which in turn promotes extensive neovascularization and augments tumor growth in vivo. This stimulation of VEGF expression depends upon the ability of alpha v beta3 integrin to cluster and promote phosphorylation of p66 Shc. These observations identify a link between beta3 integrins and VEGF in tumor growth and angiogenesis and, therefore, may influence anti-integrin as well as anti-VEGF therapeutic strategies.
authors.affiliation: Department of Molecular Cardiology, Joseph J. Jacobs Center for Thrombosis and Vascular Biology, Cleveland Clinic Foundation, Cleveland, OH 44195, USA.
authors.forename: Sarmishtha
authors.initials: S
authors.lastname: De
authors.forename: Olga
authors.initials: O
authors.lastname: Razorenova
authors.forename: Noel Patrick
authors.initials: NP
authors.lastname: McCabe
authors.forename: Timothy
authors.initials: T
authors.lastname: O'Toole
authors.forename: Jun
authors.initials: J
authors.lastname: Qin
authors.forename: Tatiana V
authors.initials: TV
authors.lastname: Byzova
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism*; D000818:Animals; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000502:physiology; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D015151:Immunoblotting; D047468:Immunoprecipitation; D039302:Integrin alphaVbeta3 / Q000378:metabolism*; D039661:Integrin beta3 / Q000235:genetics; D008279:Magnetic Resonance Imaging; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009154:Mutation / Q000235:genetics; D009369:Neoplasms / Q000378:metabolism*; D009389:Neovascularization, Pathologic / Q000378:metabolism*; D010766:Phosphorylation; D010957:Plasmids / Q000235:genetics; D055765:Shc Signaling Adaptor Proteins; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D039302:Integrin alphaVbeta3; D039661:Integrin beta3; C528024:SHC1 protein, human; D055765:Shc Signaling Adaptor Proteins; C528034:Shc1 protein, mouse; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D042461:Vascular Endothelial Growth Factor A