title: Eicosanoid regulation of angiogenesis: role of endothelial arachidonate 12-lipoxygenase.
abstract: Angiogenesis, the formation of new capillaries from preexisting blood vessels, is a multistep, highly orchestrated process involving vessel sprouting, endothelial cell migration, proliferation, tube differentiation, and survival. Eicosanoids, arachidonic acid (AA)-derived metabolites, have potent biologic activities on vascular endothelial cells. Endothelial cells can synthesize various eicosanoids, including the 12-lipoxygenase (LOX) product 12(S)-hydroxyeicosatetraenoic acid (HETE). Here we demonstrate that endogenous 12-LOX is involved in endothelial cell angiogenic responses. First, the 12-LOX inhibitor, N-benzyl-N-hydroxy-5-phenylpentanamide (BHPP), reduced endothelial cell proliferation stimulated either by basic fibroblast growth factor (bFGF) or by vascular endothelial growth factor (VEGF). Second, 12-LOX inhibitors blocked VEGF-induced endothelial cell migration, and this blockage could be partially reversed by the addition of 12(S)-HETE. Third, pretreatment of an angiogenic endothelial cell line, RV-ECT, with BHPP significantly inhibited the formation of tubelike/cordlike structures within Matrigel. Fourth, overexpression of 12-LOX in the CD4 endothelial cell line significantly stimulated cell migration and tube differentiation. In agreement with the critical role of 12-LOX in endothelial cell angiogenic responses in vitro, the 12-LOX inhibitor BHPP significantly reduced bFGF-induced angiogenesis in vivo using a Matrigel implantation bioassay. These findings demonstrate that AA metabolism in endothelial cells, especially the 12-LOX pathway, plays a critical role in angiogenesis.
authors.affiliation: Department of Radiation Oncology, Wayne State University School of Medicine, Detroit, MI, USA.
authors.forename: D
authors.initials: D
authors.lastname: Nie
authors.forename: K
authors.initials: K
authors.lastname: Tang
authors.forename: C
authors.initials: C
authors.lastname: Diglio
authors.forename: K V
authors.initials: KV
authors.lastname: Honn
mesh_terms: D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid / Q000494:pharmacology; D000818:Animals; D001092:Arachidonate 12-Lipoxygenase / Q000502:physiology*; D001710:Biotin / Q000031:analogs & derivatives / Q000494:pharmacology; D002454:Cell Differentiation; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002465:Cell Movement; D015777:Eicosanoids / Q000502:physiology*; D016228:Endothelial Growth Factors / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000166:cytology / Q000201:enzymology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D006801:Humans; D016859:Lipoxygenase Inhibitors; D008222:Lymphokines / Q000494:pharmacology; D051379:Mice; D018919:Neovascularization, Physiologic / Q000187:drug effects / Q000502:physiology*; D010590:Phalloidine / Q000031:analogs & derivatives / Q000494:pharmacology; D051381:Rats; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
chemical_list: D015777:Eicosanoids; D016228:Endothelial Growth Factors; D004791:Enzyme Inhibitors; D016859:Lipoxygenase Inhibitors; D008222:Lymphokines; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D016222:Fibroblast Growth Factor 2; C060047:4-(3-(biotinylaminohexamethylenaminocarbonyl)propanoylaminomethyl)-2-methyl-1,3-dithiolane-2-yl-(Ala(7))phalloidin; D010590:Phalloidine; D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D001710:Biotin; D001092:Arachidonate 12-Lipoxygenase