A molecular mimic demonstrates that phosphorylated human prolactin is a potent anti-angiogenic hormone

Endocr Relat Cancer. 2006 Mar;13(1):95-111. doi: 10.1677/erc.1.01076.

Abstract

S179D prolactin (PRL) is an experimentally useful mimic of naturally phosphorylated human prolactin. S179D PRL, but not unmodified PRL, was found to be anti-angiogenic in both the chorioallantoic membrane and corneal assays. Further investigation using human endothelial in vitro models showed reduced cell number, reduced tubule formation in Matrigel, and reduced migration and invasion, as a function of treatment with S179D PRL. Analysis of growth factors in human endothelial cells in response to S179D PRL showed: a decreased expression or release of endogenous PRL, heme-oxygenase-1, basic fibroblast growth factor (bFGF), angiogenin, epidermal growth factor and vascular endothelial growth factor; and an increased expression of inhibitors of matrix metalloproteases. S179D PRL also blocked signaling from bFGF in these cells. We conclude that this molecular mimic of a pituitary hormone is a potent anti-angiogenic protein, partly as a result of its ability to reduce utilization of several well-established endothelial autocrine growth loops, partly by its ability to block signaling from bFGF and partly because of its ability to decrease endothelial migration. These findings suggest that circulating levels of phosphorylated PRL may influence the progression of cancer and, furthermore, that S179D PRL may be a useful anti-angiogenic therapeutic.

Publication types

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

MeSH terms

  • Angiogenesis Inhibitors / pharmacology*
  • Animals
  • Cell Movement / drug effects
  • Chickens
  • Chorioallantoic Membrane / metabolism
  • Chorioallantoic Membrane / pathology
  • Collagen
  • Corneal Neovascularization / drug therapy
  • Drug Combinations
  • Endothelium, Vascular / cytology
  • Endothelium, Vascular / drug effects
  • Endothelium, Vascular / metabolism
  • Epidermal Growth Factor / genetics
  • Epidermal Growth Factor / metabolism
  • Fibroblast Growth Factor 2 / genetics
  • Fibroblast Growth Factor 2 / metabolism
  • Gene Expression / drug effects
  • Heme Oxygenase-1 / genetics
  • Heme Oxygenase-1 / metabolism
  • Humans
  • Laminin
  • Matrix Metalloproteinases / metabolism
  • Mice
  • Molecular Mimicry*
  • Phosphorylation / drug effects
  • Prolactin / pharmacology*
  • Proteoglycans
  • Rats
  • Rats, Sprague-Dawley
  • Ribonuclease, Pancreatic / genetics
  • Ribonuclease, Pancreatic / metabolism
  • Umbilical Veins / cytology
  • Umbilical Veins / drug effects
  • Umbilical Veins / metabolism
  • Vascular Endothelial Growth Factor A / genetics
  • Vascular Endothelial Growth Factor A / metabolism

Substances

  • Angiogenesis Inhibitors
  • Drug Combinations
  • Laminin
  • Proteoglycans
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • prolactin, Asp(179)-
  • Fibroblast Growth Factor 2
  • matrigel
  • Epidermal Growth Factor
  • Prolactin
  • Collagen
  • Heme Oxygenase-1
  • angiogenin
  • Ribonuclease, Pancreatic
  • Matrix Metalloproteinases