Effects of vitamin D(3)-binding protein-derived macrophage activating factor (GcMAF) on angiogenesis.
BACKGROUND
The vitamin D(3)-binding protein (Gc protein)-derived macrophage activating factor (GcMAF) activates tumoricidal macrophages against a variety of cancers indiscriminately. We investigated whether GcMAF also acts as an antiangiogenic factor on endothelial cells.


METHODS
The effects of GcMAF on angiogenic growth factor-induced cell proliferation, chemotaxis, and tube formation were examined in vitro by using cultured endothelial cells (murine IBE cells, porcine PAE cells, and human umbilical vein endothelial cells [HUVECs]) and in vivo by using a mouse cornea micropocket assay. Blocking monoclonal antibodies to CD36, a receptor for the antiangiogenic factor thrombospondin-1, which is also a possible receptor for GcMAF, were used to investigate the mechanism of GcMAF action.


RESULTS
GcMAF inhibited the endothelial cell proliferation, chemotaxis, and tube formation that were all stimulated by fibroblast growth factor-2 (FGF-2), vascular endothelial growth factor-A, or angiopoietin 2. FGF-2-induced neovascularization in murine cornea was also inhibited by GcMAF. Monoclonal antibodies against murine and human CD36 receptor blocked the antiangiogenic action of GcMAF on the angiogenic factor stimulation of endothelial cell chemotaxis.


CONCLUSIONS
In addition to its ability to activate tumoricidal macrophages, GcMAF has direct antiangiogenic effects on endothelial cells independent of tissue origin. The antiangiogenic effects of GcMAF may be mediated through the CD36 receptor.
Department of Molecular Microbiology and Immunology, Division of Endothelial Cell Biology, Nagasaki University Graduate School of Medicine, Nagasaki, Japan. shigeruk@net.nagasaki-u.ac.jp
Shigeru
S
Kanda
Yasushi
Y
Mochizuki
Yasuyoshi
Y
Miyata
Hiroshi
H
Kanetake
Nobuto
N
Yamamoto
D020533:Angiogenesis Inhibitors / Q000627:therapeutic use*; D042702:Angiopoietin-2; D000818:Animals; D018955:CD36 Antigens / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D002633:Chemotaxis / Q000187:drug effects; D016510:Corneal Neovascularization / Q000139:chemically induced / Q000517:prevention & control*; D016228:Endothelial Growth Factors / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000187:drug effects; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D006801:Humans; D015151:Immunoblotting; D008077:Lipoproteins, LDL; D008262:Macrophage Activation / Q000187:drug effects; D016215:Macrophage-Activating Factors / Q000627:therapeutic use*; D051379:Mice; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism; D009389:Neovascularization, Pathologic / Q000188:drug therapy*; D011506:Proteins / Q000494:pharmacology; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051076:Proto-Oncogene Proteins c-fyn; D013552:Swine; D019700:Thrombospondin 1 / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A; D014809:Vitamin D-Binding Protein / Q000627:therapeutic use*
D020533:Angiogenesis Inhibitors; D042702:Angiopoietin-2; D018955:CD36 Antigens; D016228:Endothelial Growth Factors; D008077:Lipoproteins, LDL; D016215:Macrophage-Activating Factors; D011506:Proteins; D011518:Proto-Oncogene Proteins; D019700:Thrombospondin 1; D042461:Vascular Endothelial Growth Factor A; D014809:Vitamin D-Binding Protein; C101908:vitamin D-binding protein-macrophage activating factor; D016222:Fibroblast Growth Factor 2; C494957:FYN protein, human; C494960:Fyn protein, mouse; D051076:Proto-Oncogene Proteins c-fyn; D020929:Mitogen-Activated Protein Kinase Kinases