Prostate cancer: a model of integration of genomic and non-genomic effects of the androgen receptor in cell lines model

Steroids. 2008 Oct;73(9-10):1030-7. doi: 10.1016/j.steroids.2008.01.028. Epub 2008 Feb 15.

Abstract

Androgens and the androgen receptor (AR) are involved both in early tumorigenesis of prostate cancer (PCa) and in androgen-refractory disease. The role of AR signalling has also been highlighted by the fusion gene TMPRSS2:ERG recently identified in the majority of PCa. Several data indicate that re-expression of AR in PCa cell lines confers a less aggressive phenotype. We observed that re-expression of AR in the AR-negative cells PC3 decreases anchorage-independent growth and Matrigel invasiveness of PC3-AR cells where plasma membrane interaction between AR and EGFR led to an interference with downstream signalling and internalization of activated EGFR. Our data evidenced a shift of EGFR internalization pathway from the clathrin-coated pit one mediating signalling and recycling of EGFR to the lipid raft-mediated one mainly involved in lysosomal degradation of EGFR. These effects involved an altered recruitment to EGFR of the adaptor proteins Grb2 and c-Cbl followed by a reduced ubiquitination of EGFR. Our preliminary results suggest that in PC3-AR cells a pool of classical AR is located within cholesterol-rich membrane microdomains (namely as lipid rafts) and a population of EGFR is within cholesterol-rich membrane microdomains too. However, AR and EGFR membrane interaction that is increased by rapid androgen signalling is not within cholesterol-rich membrane microdomains. Our data enlighten that the crosstalk between genotropic and non-genotropic AR signalling interferes with signalling of EGFR in response to ligand leading to a lower invasive phenotype of AR-positive PCa cells.

Publication types

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

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Cell Membrane / metabolism
  • Cholesterol / metabolism
  • ErbB Receptors / metabolism
  • Genome
  • Humans
  • Lysosomes / metabolism
  • Male
  • Membrane Microdomains
  • Models, Biological
  • Phenotype
  • Prostatic Neoplasms / metabolism
  • Prostatic Neoplasms / pathology*
  • Receptors, Androgen / metabolism*
  • Signal Transduction

Substances

  • Receptors, Androgen
  • Cholesterol
  • ErbB Receptors