title: Induction of apoptotic cell death in vascular endothelial cells cultured in three-dimensional collagen lattice.
abstract: Endothelial cells derived from fetal bovine aorta (BAECs) undergo apoptosis in three-dimensional (3-D) type I collagen lattice in the absence of specific angiogenic factor. In the presence of angiogenic factor, BAECs survive and form a capillary-like tube structure in 3-D culture. In the present study we elucidate the mechanisms of BAECs apoptosis or survival and tube formation in 3-D culture. When BAECs embedded in collagen lattice were cultured with angiogenic factor (fibroblast growth factor-2 (FGF-2) or 4beta-phorbol 12-myristate 13-acetate (PMA)) in the presence of PD98059, a specific inhibitor of mitogen-activated protein kinase kinase, BAECs did not form tube structures and underwent apoptosis in collagen lattice. Function-blocking antibody against alphavbeta3 integrin also inhibited tube formation and induced apoptosis in 3-D culture in the presence of angiogenic factors. Exposure of BAECs to FGF-2 and PMA had no effect on the alphavbeta3 integrin expression but induced the activation of alphavbeta3 integrin. PD98059 attenuated alphavbeta3 integrin activation in response to angiogenic factor. KB-R8301, a hydroxamic acid-based matrix metalloproteinase (MMP) inhibitor, prevented apoptotic cell death in the absence of angiogenic factor in 3-D culture and enhanced capillary-like tube formation in the presence of angiogenic factor, which was not inhibited by the anti-alphavbeta3 integrin antibody. The results suggest that angiogenic factor-induced alphavbeta3 integrin activation through the MEK-ERK pathway regulates the BAEC fate between apoptosis and angiogenesis in collagen lattice. MMP derived from BAECs seems to play a key role in the release of cryptic ligands for alphavbeta3 integrin from intact collagen.
authors.affiliation: Department of Geriatrics, Nagoya University School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, 466-8550, Japan. kuzuya@med.nagoyau.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Kuzuya
authors.forename: S
authors.initials: S
authors.lastname: Satake
authors.forename: M A
authors.initials: MA
authors.lastname: Ramos
authors.forename: S
authors.initials: S
authors.lastname: Kanda
authors.forename: T
authors.initials: T
authors.lastname: Koike
authors.forename: K
authors.initials: K
authors.lastname: Yoshino
authors.forename: S
authors.initials: S
authors.lastname: Ikeda
authors.forename: A
authors.initials: A
authors.lastname: Iguchi
mesh_terms: D043925:Angiogenesis Inducing Agents / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis; D002417:Cattle; D002448:Cell Adhesion; D002470:Cell Survival; D002478:Cells, Cultured; D003094:Collagen; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D006877:Hydroxamic Acids / Q000494:pharmacology; D016023:Integrins / Q000378:metabolism; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors / Q000378:metabolism; D018919:Neovascularization, Physiologic; D047428:Protein Kinase Inhibitors; D011494:Protein Kinases / Q000378:metabolism; D019030:Receptors, Vitronectin / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D043925:Angiogenesis Inducing Agents; D005419:Flavonoids; D006877:Hydroxamic Acids; D016023:Integrins; C423012:KB R8301; D047428:Protein Kinase Inhibitors; D019030:Receptors, Vitronectin; D016222:Fibroblast Growth Factor 2; D003094:Collagen; D011494:Protein Kinases; D008666:Metalloendopeptidases; D013755:Tetradecanoylphorbol Acetate; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one