Mitogen-activated protein kinase activation mediates PDGF-directed migration of RPE cells

Exp Cell Res. 1998 Feb 25;239(1):11-5. doi: 10.1006/excr.1997.3873.


Growth factor-directed migration is a critical component of the wound healing response although little is known about the signaling pathways involved. We examined the effect of inhibiting the mitogen-activated protein kinase (MAPK) pathway on platelet-derived growth factor (PDGF) and fibronectin-induced cell migration of human retinal pigment epithelial (RPE) cells. Using transwell cell-culture chambers, the effect of PDGF-BB (10-50 ng/ml) and fibronectin on components of migration was measured with or without the MAPK pathway inhibitor PD98059 (10-30 microM) MAPK activation of serum-starved cells by PDGF-BB was demonstrated by an immunoprecipitation/kinase assay and by immunohistochemistry using antibody specific for phosphorylated MAPK. PDGF-BB (10 ng/ml) stimulated MAPK activity in RPE (10 min) and its nuclear localization (1 h). PD98059 inhibited the activation of MAPK by PDGF-BB or serum. PDGF-BB stimulated RPE chemokinesis, chemotaxis, and haptotaxis; chemokinesis was additively increased and chemotaxis synergistically increased by the presence of a fibronectin substratum. PD98059 potently inhibited fibronectin-induced haptotaxis and PDGF-BB-induced chemotaxis but inhibited chemokinesis only at higher PDGF-BB (50 ng/ml) concentrations in the presence of fibronectin substratum. These results demonstrate that MAPK is critically involved in multiple components of RPE migration in vitro and suggest the potential of targeting MAPK to inhibit RPE migration in vivo.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Becaplermin
  • Calcium-Calmodulin-Dependent Protein Kinases / antagonists & inhibitors
  • Calcium-Calmodulin-Dependent Protein Kinases / metabolism*
  • Cell Line
  • Cell Movement / drug effects
  • Cell Nucleus / enzymology
  • Enzyme Activation
  • Enzyme Inhibitors / pharmacology
  • Fibronectins / pharmacology
  • Flavonoids / pharmacology
  • Humans
  • Kinetics
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3
  • Mitogen-Activated Protein Kinases*
  • Phosphorylation
  • Pigment Epithelium of Eye / cytology
  • Pigment Epithelium of Eye / drug effects
  • Pigment Epithelium of Eye / physiology*
  • Platelet-Derived Growth Factor / pharmacology*
  • Proto-Oncogene Proteins c-sis


  • Enzyme Inhibitors
  • Fibronectins
  • Flavonoids
  • Platelet-Derived Growth Factor
  • Proto-Oncogene Proteins c-sis
  • Becaplermin
  • Calcium-Calmodulin-Dependent Protein Kinases
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3
  • Mitogen-Activated Protein Kinases
  • 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one