Proline-rich tyrosine kinase 2 via enhancing signal transducer and activator of transcription 3-dependent cJun expression mediates retinal neovascularization

Sci Rep. 2016 May 23:6:26480. doi: 10.1038/srep26480.

Abstract

Despite the involvement of proline-rich tyrosine kinase 2 (Pyk2) in endothelial cell angiogenic responses, its role in pathological retinal angiogenesis is not known. In the present study, we show that vascular endothelial growth factor A (VEGFA) induces Pyk2 activation in mediating human retinal microvascular endothelial cell (HRMVEC) migration, sprouting and tube formation. Downstream to Pyk2, VEGFA induced signal transducer and activator of transcription 3 (STAT3) activation and cJun expression in the modulation of HRMVEC migration, sprouting and tube formation. Consistent with these observations, hypoxia induced activation of Pyk2-STAT3-cJun signaling axis and siRNA-mediated downregulation of Pyk2, STAT3 or cJun levels substantially inhibited hypoxia-induced retinal endothelial cell proliferation, tip cell formation and neovascularization. Together, these observations suggest that activation of Pyk2-mediated STAT3-cJun signaling is required for VEGFA-induced HRMVEC migration, sprouting and tube formation in vitro and hypoxia-induced retinal endothelial cell proliferation, tip cell formation and neovascularization in vivo.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cell Hypoxia
  • Cell Movement / drug effects
  • Cells, Cultured
  • Disease Models, Animal
  • Endothelial Cells / cytology
  • Endothelial Cells / drug effects
  • Endothelial Cells / metabolism
  • Enzyme Activation / drug effects
  • Focal Adhesion Kinase 2 / metabolism*
  • Humans
  • Mice
  • Proto-Oncogene Proteins c-jun / metabolism*
  • Retina / cytology
  • Retina / drug effects
  • Retina / metabolism
  • Retinal Neovascularization / metabolism*
  • STAT3 Transcription Factor / metabolism*
  • Signal Transduction / drug effects
  • Vascular Endothelial Growth Factor A / pharmacology*

Substances

  • Proto-Oncogene Proteins c-jun
  • STAT3 Transcription Factor
  • STAT3 protein, human
  • Vascular Endothelial Growth Factor A
  • Focal Adhesion Kinase 2
  • PTK2B protein, human