Non-competitive androgen receptor inhibition in vitro and in vivo

Proc Natl Acad Sci U S A. 2009 Apr 28;106(17):7233-8. doi: 10.1073/pnas.0807282106. Epub 2009 Apr 10.


Androgen receptor (AR) inhibitors are used to treat multiple human diseases, including hirsutism, benign prostatic hypertrophy, and prostate cancer, but all available anti-androgens target only ligand binding, either by reduction of available hormone or by competitive antagonism. New strategies are needed, and could have an important impact on therapy. One approach could be to target other cellular mechanisms required for receptor activation. In prior work, we used a cell-based assay of AR conformation change to identify non-ligand inhibitors of AR activity. Here, we characterize 2 compounds identified in this screen: pyrvinium pamoate, a Food and Drug Administration-approved drug, and harmol hydrochloride, a natural product. Each compound functions by a unique, non-competitive mechanism and synergizes with competitive antagonists to disrupt AR activity. Harmol blocks DNA occupancy by AR, whereas pyrvinium does not. Pyrvinium inhibits AR-dependent gene expression in the prostate gland in vivo, and induces prostate atrophy. These results highlight new therapeutic strategies to inhibit AR activity.

Publication types

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

MeSH terms

  • Androgen Receptor Antagonists*
  • Animals
  • Cell Line
  • Cell Proliferation / drug effects
  • Harmine / analogs & derivatives
  • Harmine / chemistry
  • Harmine / pharmacology
  • Humans
  • Male
  • Mice
  • Molecular Structure
  • Pyrvinium Compounds / chemistry
  • Pyrvinium Compounds / pharmacology
  • Receptors, Androgen / genetics
  • Receptors, Androgen / metabolism*


  • Androgen Receptor Antagonists
  • Pyrvinium Compounds
  • Receptors, Androgen
  • harmol
  • Harmine
  • pyrvinium