title: MicroRNA-223 antagonizes angiogenesis by targeting β1 integrin and preventing growth factor signaling in endothelial cells.
abstract: BACKGROUND
  Endothelial cells in situ are largely quiescent, and their isolation and culture are associated with the switch to a proliferative phenotype.
  
  
  OBJECTIVE
  To identify antiangiogenic microRNAs expressed by native endothelial cells that are altered after isolation and culture, as well as the protein targets that regulate responses to growth factors.
  
  
  RESULTS
  Profiling studies revealed that miR-223 was highly expressed in freshly isolated human, murine, and porcine endothelial cells, but those levels decreased in culture. In primary cultures of endothelial cells, vascular endothelial cell growth factor and basic fibroblast growth factor further decreased miR-223 expression. The overexpression of precursor-miR-223 did not affect basal endothelial cell proliferation but abrogated vascular endothelial cell growth factor-induced and basic fibroblast growth factor-induced proliferation, as well as migration and sprouting. Inhibition of miR-223 in vivo using specific antagomirs potentiated postnatal retinal angiogenesis in wild-type mice, whereas recovery of perfusion after femoral artery ligation and endothelial sprouting from aortic rings from adult miR-223(-/y) animals were enhanced. MiR-223 overexpression had no effect on the growth factor-induced activation of ERK1/2 but inhibited the vascular endothelial cell growth factor-induced and basic fibroblast growth factor-induced phosphorylation of their receptors and activation of Akt. β1 integrin was identified as a target of miR-223 and its downregulation reproduced the defects in growth factor receptor phosphorylation and Akt signaling seen after miR-223 overexpression. Reintroduction of β1 integrin into miR-223-ovexpressing cells was sufficient to rescue growth factor signaling and angiogenesis.
  
  
  CONCLUSIONS
  These results indicate that miR-223 is an antiangiogenic microRNA that prevents endothelial cell proliferation at least partly by targeting β1 integrin.
authors.affiliation: From the Institute for Vascular Signalling, Centre for Molecular Medicine, Goethe University and DZHK (German Centre for Cardiovascular Research) partner site Rhine-Main, Frankfurt, Germany (L.S., B.F., N.Z., T.F., J.H., A.E., R.P., I.F.); and Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine, Goethe University, Frankfurt am Main, Germany (H.H.).
authors.forename: Lei
authors.initials: L
authors.lastname: Shi
authors.forename: Beate
authors.initials: B
authors.lastname: Fisslthaler
authors.forename: Nina
authors.initials: N
authors.lastname: Zippel
authors.forename: Timo
authors.initials: T
authors.lastname: Frömel
authors.forename: Jiong
authors.initials: J
authors.lastname: Hu
authors.forename: Amro
authors.initials: A
authors.lastname: Elgheznawy
authors.forename: Heinrich
authors.initials: H
authors.lastname: Heide
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Popp
authors.forename: Ingrid
authors.initials: I
authors.lastname: Fleming
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D016503:Drug Delivery Systems; D016228:Endothelial Growth Factors / Q000037:antagonists & inhibitors* / Q000502:physiology*; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism*; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D019012:Integrin beta1 / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D035683:MicroRNAs / Q000502:physiology*; D018919:Neovascularization, Physiologic / Q000187:drug effects / Q000235:genetics*; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics*; D013552:Swine
chemical_list: D016228:Endothelial Growth Factors; D019012:Integrin beta1; C544877:MIRN223 microRNA, mouse; D035683:MicroRNAs
keywords: angiogenesis inhibitors; hindlimb; microRNA-223 mouse; receptors, vascular endothelial growth factor; β1 integrin