Insulin-like growth factor binding protein-7 (IGFBP7) blocks vascular endothelial cell growth factor (VEGF)-induced angiogenesis in human vascular endothelial cells.
Insulin-like growth factor binding protein-7 (IGFBP7) and vascular endothelial growth factor (VEGF) are expressed in vascular endothelial cells in several tumor types. In this study, we examined the effect of IGFBP7 on VEGF-induced tube formation in cultured human umbilical vein endothelial cells (HUVECs) and its potential action in the modulation of VEGF signaling in vascular cells. IGFBP7 treatment suppressed VEGF-induced tube formation, proliferation, and the phosphorylation of mitogen-activated protein kinase kinase (MEK) and extracellular signal-regulated kinase (ERK) 1/2 in HUVECs. IGFBP7 attenuated VEGF-enhanced cyclooxygenase (COX)-2 and VEGF mRNA expression, and prostaglandin E(2) secretion. Knocking down endogenous IGFBP7 enhanced COX-2 and VEGF mRNA expression. A significant increase in IGFBP7-induced caspases was not observed in the presence of VEGF. These findings indicate that IGFBP7 can modulate the stimulatory effect of VEGF on angiogenesis by interfering with VEGF expression as well as VEGF signaling and not by inducing apoptosis.
Tamura
Kazuhiro
K
Department of Endocrine Pharmacology, Tokyo University of Pharmacy & Life Sciences, Horinouchi 1432-1, Hachioji, Tokyo, 192-0392, Japan. hiro@ps.toyaku.ac.jp
Hashimoto
Keisuke
K
Suzuki
Kenta
K
Yoshie
Mikihiro
M
Kutsukake
Masahiko
M
Sakurai
Toshihiro
T
D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D003094:Collagen / Q000378:metabolism; D016895:Culture Media, Serum-Free; D051546:Cyclooxygenase 2 / Q000378:metabolism; D015232:Dinoprostone / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D042783:Endothelial Cells / Q000187:drug effects*; D004730:Endothelium, Vascular / Q000187:drug effects*; D005109:Extracellular Matrix / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D018969:Insulin-Like Growth Factor Binding Proteins / Q000235:genetics / Q000494:pharmacology*; D007797:Laminin / Q000378:metabolism; D018919:Neovascularization, Physiologic / Q000187:drug effects* / Q000502:physiology; D010766:Phosphorylation / Q000187:drug effects; D011509:Proteoglycans / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D013997:Time Factors; D014162:Transfection; D014471:Umbilical Veins / Q000166:cytology; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology*
D016895:Culture Media, Serum-Free; D004338:Drug Combinations; D018969:Insulin-Like Growth Factor Binding Proteins; D007797:Laminin; D011509:Proteoglycans; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D011994:Recombinant Proteins; D042461:Vascular Endothelial Growth Factor A; C102529:insulin-like growth factor binding protein-related protein 1; C059485:matrigel; D003094:Collagen; D051546:Cyclooxygenase 2; D048049:Extracellular Signal-Regulated MAP Kinases; D015232:Dinoprostone