Crosstalk between EGFR and TrkB enhances ovarian cancer cell migration and proliferation

Int J Oncol. 2006 Oct;29(4):1003-11.

Abstract

Ovarian cancer remains the leading cause of fatality among all gynecologic cancers, although promising therapies are in the making. It has been speculated that metastasis is critical for ovarian cancer, and yet the molecular mechanisms of metastasis in ovarian cancer are poorly understood. Growth factors have been proven to play important roles in cell migration associated with metastasis, and inhibition of growth factor receptors and their distinct cell signaling pathways has been intensively studied, and yet the uncovered interaction or crosstalk among various growth factor receptors complicates this otherwise promising approach. We investigated the crosstalk between EGFR and TrkB, both of which have been known to be important in cell survival and migration in response to EGF and BDNF. Our results showed that both EGF and BDNF induced cell migration and cell proliferation in cultured human ovarian cancer cells (Caov3 cell line). EGF and BDNF transactivated TrkB and EGFR respectively, and activated downstream cell survival components such as Akt. EGFR and TrkB kinase inhibitors inhibited EGF- and BDNF-induced TrkB and EGFR activation and Akt phosphorylation, and cell proliferation and migration. Using EGFR knockout cells, we further demonstrated that EGFR is required for EGF-induced cell migration. Collectively, our data indicate that EGFR and TrkB crosstalk each other in response to EGF and BDNF, leading to cell survival pathway activation in ovarian cancer cells. Our data suggest that a combination of inhibitors of both receptors with cell survival pathway inhibitors would provide a better outcome in the clinical treatment of ovarian cancer.

Publication types

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

MeSH terms

  • Brain-Derived Neurotrophic Factor / antagonists & inhibitors
  • Brain-Derived Neurotrophic Factor / pharmacology
  • Cell Movement / drug effects
  • Cell Proliferation / drug effects
  • Enzyme Inhibitors / pharmacology
  • Epidermal Growth Factor / antagonists & inhibitors
  • Epidermal Growth Factor / pharmacology
  • ErbB Receptors / agonists
  • ErbB Receptors / genetics
  • ErbB Receptors / metabolism*
  • Female
  • Humans
  • Ovarian Neoplasms / metabolism*
  • Ovarian Neoplasms / pathology*
  • Phosphoinositide-3 Kinase Inhibitors
  • Proto-Oncogene Proteins c-akt / agonists
  • Proto-Oncogene Proteins c-akt / antagonists & inhibitors
  • Receptor, trkB / agonists
  • Receptor, trkB / genetics
  • Receptor, trkB / metabolism*
  • Transcriptional Activation
  • Tumor Cells, Cultured

Substances

  • Brain-Derived Neurotrophic Factor
  • Enzyme Inhibitors
  • Phosphoinositide-3 Kinase Inhibitors
  • Epidermal Growth Factor
  • ErbB Receptors
  • Receptor, trkB
  • Proto-Oncogene Proteins c-akt