title: Blockade of alpha v beta3 and alpha v beta5 integrins by RGD mimetics induces anoikis and not integrin-mediated death in human endothelial cells.
abstract: Alpha v integrins are thought to play an important role in tumor angiogenesis. However, discrepancies between findings with Arg-Gly-Asp (RGD) mimetics, which block angiogenesis in animal models, and knockout mice, in which loss of some alpha v integrins enhances tumor angiogenesis, raise questions concerning the function of these integrins and the precise role of alpha v substrate mimetics in antiangiogenic therapies. We have examined the effects of a novel non-peptide RGD mimetic, S 36578-2, on human endothelial cells to elucidate its antagonist activity and to identify possible agonist functions. S 36578-2 is highly selective for alpha v beta3 and alpha v beta5 integrins and induces detachment, caspase-8 activation, and apoptosis in human umbilical endothelial cells (HUVECs) plated on vitronectin. Importantly, the compound has no effect on the morphology or survival of cells plated on interstitial matrix components such as fibronectin, and it does not potentiate the apoptotic process in suspended cells. Identical results were obtained with a cyclic RGD peptide with similar target specificity. In microvascular endothelial cells, S 36578-2-induced death was also linked to its antiadhesive effect, with established lines markedly more resistant than primary cultures to the antiadhesive and proapoptotic effects. Altogether, these findings have important implications for the development of this class of antiangiogenics.
authors.affiliation: Centre National de Recherche Scientifique, Unité Mixte de Recherche (CNRS UMR) 6543, Centre Antoine Lacassagne, Nice, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Maubant
authors.forename: Dominique
authors.initials: D
authors.lastname: Saint-Dizier
authors.forename: Morgane
authors.initials: M
authors.lastname: Boutillon
authors.forename: Francoise
authors.initials: F
authors.lastname: Perron-Sierra
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Casara
authors.forename: John A
authors.initials: JA
authors.lastname: Hickman
authors.forename: Gordon C
authors.initials: GC
authors.lastname: Tucker
authors.forename: Ellen
authors.initials: E
authors.lastname: Van Obberghen-Schilling
mesh_terms: D023102:Anoikis / Q000187:drug effects / Q000502:physiology*; D017209:Apoptosis / Q000187:drug effects; D001567:Benzocycloheptenes / Q000494:pharmacology*; D018929:Cell Culture Techniques; D016923:Cell Death / Q000187:drug effects / Q000502:physiology; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D005312:Fetal Blood / Q000166:cytology; D006801:Humans; D039302:Integrin alphaVbeta3 / Q000037:antagonists & inhibitors* / Q000187:drug effects / Q000235:genetics; D016023:Integrins / Q000037:antagonists & inhibitors* / Q000187:drug effects / Q000235:genetics; D009369:Neoplasms / Q000098:blood supply; D009389:Neovascularization, Pathologic; D009842:Oligopeptides / Q000494:pharmacology*; D019030:Receptors, Vitronectin / Q000037:antagonists & inhibitors* / Q000187:drug effects / Q000235:genetics; D014471:Umbilical Veins; D019096:Vitronectin / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: C514976:5-(7-((4-(pyridin-2-ylamino)butyrylamino)methyl)-6,9-dihydro-5H-benzocyclohepten-5-yl)acetic acid; D001567:Benzocycloheptenes; D039302:Integrin alphaVbeta3; D016023:Integrins; D009842:Oligopeptides; D019030:Receptors, Vitronectin; D019096:Vitronectin; C064660:integrin alphaVbeta5; D005680:gamma-Aminobutyric Acid; C047981:arginyl-glycyl-aspartic acid