Inhibition of human endothelial cell proliferation by ShIF, a vacuolar H(+)-ATPase-like protein.
ShIF is a bone marrow stroma cell-derived factor originally identified to support proliferation of bone marrow cells in vitro. This protein shares high sequence homology to the yeast vacuolar H(+)-ATPase subunit, Vph1p, and the 116 kDa proton pump of the rat and bovine synaptic vesicle, Vpp1. We examined the function of ShIF in the proliferation of human umbilical vein endothelial cells (HUVEC). ShIF inhibited HUVEC proliferation in a dose-dependent manner. Recombinant ShIF added at 10 and 20 ng/ml inhibited HUVEC proliferation by 21.6 and 44.3%, respectively and increasing the concentration of ShIF to 100 ng/ml inhibited proliferation by as much as 55.5%. When HUVEC cells were cultured at various concentrations of ShIF in the presence of anti-ShIF antibody, the inhibitory effects of ShIF to HUVEC proliferation were abrogated by 89-91% indicating that the activity of ShIF to HUVEC was specific. HUVEC cultured in the presence of ShIF and bafilomycin, a specific inhibitor of ATPase, resulted to a 90% growth inhibition. Thus, ShIF may act as an antagonist to the ATPase complex by disrupting the production of cellular ATP thereby decreasing the ability of HUVEC to proliferate.
Tulin
Edgardo E
EE
Chugai Research Institute for Molecular Medicine Incorporated, 153-2 Nagai, Niihari, Ibaraki, 300-4101, Japan. tulin@ims.u-tokyo.ac.jp
Onoda
Nobuhisa
N
Hasegawa
Masakazu
M
Nomura
Hitoshi
H
Kitamura
Toshio
T
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000906:Antibodies / Q000494:pharmacology; D019556:COS Cells; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004727:Endothelium / Q000166:cytology* / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006133:Growth Substances / Q000276:immunology / Q000378:metabolism / Q000494:pharmacology*; D006801:Humans; D018942:Macrolides; D017494:Proton Pumps; D006180:Proton-Translocating ATPases; D025262:Vacuolar Proton-Translocating ATPases / Q000037:antagonists & inhibitors / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D000906:Antibodies; C432920:Atp6v0a2 protein, mouse; D004791:Enzyme Inhibitors; D006133:Growth Substances; D018942:Macrolides; D017494:Proton Pumps; C057620:bafilomycin A; D025262:Vacuolar Proton-Translocating ATPases; D006180:Proton-Translocating ATPases