Androgen receptor an additional hormonal target in many breast cancers
 

Many breast cancers depend on hormones including estrogen or progesterone for their survival and proliferation. Eight years of lab work at the University of Colorado Cancer Center and elsewhere suggest that the androgen (AR) receptor is an additional hormonal target in many breast cancers. Block AR+ breast cancer's ability to access androgen and you block the cancer's ability to survive.

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Re: Androgen receptor an additional hormonal target in many breast cancers
 

Wow. Heard of this but..up to 88% of ER+ BC ise AR+?
So..not to take anything away from Medivation but...other readily available androgen targeted prostate cancer drugs would seem fair game: Lupron shot (reduces testosterone production), Casodex pill (blocks Androgen receptor) etc.
Wonder how much crosstalk there is between all these receptors.
If you did a Her, ER, AR blockade..might be a pretty effective, lower toxicity all oral regimen.