Non-competitive androgen receptor inhibition in vitro and in vivo.
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.
Department of Neurology, University of California San Francisco, San Francisco, CA 94115, USA.
Jeremy O
JO
Jones
Eric C
EC
Bolton
Yong
Y
Huang
Clementine
C
Feau
R Kiplin
RK
Guy
Keith R
KR
Yamamoto
Byron
B
Hann
Marc I
MI
Diamond
D059002:Androgen Receptor Antagonists; D000818:Animals; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D006247:Harmine / Q000031:analogs & derivatives / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D008297:Male; D051379:Mice; D015394:Molecular Structure; D011774:Pyrvinium Compounds / Q000737:chemistry / Q000494:pharmacology; D011944:Receptors, Androgen / Q000235:genetics / Q000378:metabolism*
D059002:Androgen Receptor Antagonists; D011774:Pyrvinium Compounds; D011944:Receptors, Androgen; C001326:harmol; D006247:Harmine; C024631:pyrvinium