Interaction between the androgen receptor and RNase L mediates a cross-talk between the interferon and androgen signaling pathways

J Biol Chem. 2005 Nov 25;280(47):38898-901. doi: 10.1074/jbc.C500324200. Epub 2005 Sep 14.

Abstract

Signaling by androgens and interferons (IFN) plays an important role in prostate cancer initiation and progression. Using microarray analysis, we describe here a functional cross-talk between dihydrotestosterone and interferon signaling. Glutathione S-transferase pull-down and co-immunoprecipitation experiments reveal that the androgen receptor and the interferon-activated RNase L interact with each other in a ligand-dependent manner. Furthermore, overexpression of wild type RNase L confers IFN sensitivity to a dihydrotestosterone-inducible reporter gene, whereas R462Q-mutated RNase L does not. Based on our data we hypothesize that in 22RV1 cells, activated androgen receptor (AR) contributes to the insensitivity to IFN of the cell. Accordingly, we show that AR knockdown restores responsiveness to IFNgamma. Our findings support a model in which both the activation of AR and the down-regulation of IFN signaling can synergize to promote cell survival and suppress apoptosis. This model provides the molecular basis to understand how mutated RNase L can lead to early onset PCa and illustrates how inflammatory cytokines and nuclear hormone signaling contribute to tumor development.

MeSH terms

  • Androgens / metabolism
  • Apoptosis
  • Breast Neoplasms / genetics
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology
  • Cell Line, Tumor
  • Cell Survival
  • Dihydrotestosterone / pharmacology
  • Endoribonucleases / genetics
  • Endoribonucleases / metabolism*
  • Enzyme Activation
  • Female
  • Gene Expression / drug effects
  • Genes, Reporter
  • Humans
  • Interferon-gamma / pharmacology
  • Interferons / metabolism*
  • Ligands
  • Male
  • Models, Biological
  • Mutation
  • Prostatic Neoplasms / genetics
  • Prostatic Neoplasms / metabolism
  • Prostatic Neoplasms / pathology
  • Receptor Cross-Talk
  • Receptors, Androgen / genetics
  • Receptors, Androgen / metabolism*
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Signal Transduction

Substances

  • Androgens
  • Ligands
  • Receptors, Androgen
  • Recombinant Proteins
  • Dihydrotestosterone
  • Interferon-gamma
  • Interferons
  • Endoribonucleases
  • 2-5A-dependent ribonuclease