title: GPR4 plays a critical role in endothelial cell function and mediates the effects of sphingosylphosphorylcholine.
abstract: Angiogenesis is critical for many physiological and pathological processes. We show here that the lipid sphingosylphosphorylcholine (SPC) induces angiogenesis in vivo and GPR4 is required for the biological effects of SPC on endothelial cells (EC). In human umbilical vein EC, down-regulation of GPR4 specifically inhibits SPC-, but not sphingosine-1-phosphate-, or vascular endothelial growth factor (VEGF)-induced tube formation. Re-introduction of GPR4 fully restores the activity of SPC. In microvascular EC, GPR4 plays a pivotal role in cell survival, growth, migration, and tube formation through both SPC-dependent and -independent pathways. The biological effects resulting from SPC/GPR4 interactions involve the activation of both phosphatidylinositol-3 kinase and Akt. Moreover, the effects of SPC on EC require SPC induced trans-phosphorylation and activation of the VEGF receptor 2. These results identify SPC and its receptor, GPR4, as critical regulators of the angiogenic potential of EC.
authors.affiliation: Department of Cancer Biology, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
authors.forename: Kwan-Sik
authors.initials: KS
authors.lastname: Kim
authors.forename: Juan
authors.initials: J
authors.lastname: Ren
authors.forename: Ying
authors.initials: Y
authors.lastname: Jiang
authors.forename: Quteba
authors.initials: Q
authors.lastname: Ebrahem
authors.forename: Russell
authors.initials: R
authors.lastname: Tipps
authors.forename: Kelly
authors.initials: K
authors.lastname: Cristina
authors.forename: Yi-jin
authors.initials: YJ
authors.lastname: Xiao
authors.forename: Jing
authors.initials: J
authors.lastname: Qiao
authors.forename: Kevin L
authors.initials: KL
authors.lastname: Taylor
authors.forename: Hazel
authors.initials: H
authors.lastname: Lum
authors.forename: Bela
authors.initials: B
authors.lastname: Anand-Apte
authors.forename: Yan
authors.initials: Y
authors.lastname: Xu
mesh_terms: D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D002455:Cell Division / Q000502:physiology; D002465:Cell Movement / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D002642:Chick Embryo; D042783:Endothelial Cells / Q000502:physiology*; D004789:Enzyme Activation; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008246:Lysophospholipids / Q000494:pharmacology; D018919:Neovascularization, Physiologic / Q000187:drug effects / Q000502:physiology*; D051058:Oncogene Protein v-akt / Q000378:metabolism; D010446:Peptide Fragments / Q000276:immunology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010767:Phosphorylcholine / Q000031:analogs & derivatives* / Q000494:pharmacology; D034741:RNA, Small Interfering / Q000494:pharmacology; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D040262:Receptors, Vascular Endothelial Growth Factor / Q000502:physiology; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D014471:Umbilical Veins; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology
chemical_list: D000906:Antibodies; C091670:GPR4 protein, human; D008246:Lysophospholipids; D010446:Peptide Fragments; D034741:RNA, Small Interfering; D043562:Receptors, G-Protein-Coupled; D042461:Vascular Endothelial Growth Factor A; C005356:sphingosine phosphorylcholine; D010767:Phosphorylcholine; C060506:sphingosine 1-phosphate; D019869:Phosphatidylinositol 3-Kinases; D040262:Receptors, Vascular Endothelial Growth Factor; D051058:Oncogene Protein v-akt; D013110:Sphingosine