Targeting NCK-Mediated Endothelial Cell Front-Rear Polarity Inhibits Neovascularization

Circulation. 2016 Jan 26;133(4):409-21. doi: 10.1161/CIRCULATIONAHA.115.017537. Epub 2015 Dec 9.

Abstract

Background: Sprouting angiogenesis is a key process driving blood vessel growth in ischemic tissues and an important drug target in a number of diseases, including wet macular degeneration and wound healing. Endothelial cells forming the sprout must develop front-rear polarity to allow sprout extension. The adaptor proteins Nck1 and 2 are known regulators of cytoskeletal dynamics and polarity, but their function in angiogenesis is poorly understood. Here, we show that the Nck adaptors are required for endothelial cell front-rear polarity and migration downstream of the angiogenic growth factors VEGF-A and Slit2.

Methods and results: Mice carrying inducible, endothelial-specific Nck1/2 deletions fail to develop front-rear polarized vessel sprouts and exhibit severe angiogenesis defects in the postnatal retina and during embryonic development. Inactivation of NCK1 and 2 inhibits polarity by preventing Cdc42 and Pak2 activation by VEGF-A and Slit2. Mechanistically, NCK binding to ROBO1 is required for both Slit2- and VEGF-induced front-rear polarity. Selective inhibition of polarized endothelial cell migration by targeting Nck1/2 prevents hypersprouting induced by Notch or Bmp signaling inhibition, and pathological ocular neovascularization and wound healing, as well.

Conclusions: These data reveal a novel signal integration mechanism involving NCK1/2, ROBO1/2, and VEGFR2 that controls endothelial cell front-rear polarity during sprouting angiogenesis.

Keywords: Slit-Robo; VEGF; angiogenesis, pathologic; cell movement; cell polarity; neovascularization, pathologic; vascular biology.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / deficiency
  • Adaptor Proteins, Signal Transducing / genetics*
  • Amino Acid Sequence
  • Animals
  • Cell Polarity / physiology*
  • Endothelial Cells / physiology*
  • Gene Deletion*
  • Gene Targeting / methods
  • HEK293 Cells
  • Human Umbilical Vein Endothelial Cells
  • Humans
  • Mice
  • Mice, Knockout
  • Molecular Sequence Data
  • Neovascularization, Physiologic / physiology*
  • Oncogene Proteins / deficiency
  • Oncogene Proteins / genetics*

Substances

  • Adaptor Proteins, Signal Transducing
  • Nck protein
  • Nck2 protein, mouse
  • Oncogene Proteins