Multiple Subtypes Of Triple Negative Breast Cancer Are Dependent On Androgen Receptor

Triple negative breast cancer (TNBC) constitutes 10-20% of invasive breast carcinomas and has the lowest five-year survival rate. Currently, there are no targeted therapies for TNBC. Recent studies demonstrate that the androgen receptor (AR) is expressed in up to a third of TNBC. AR is highly expressed in the luminal AR (LAR) molecular TNBC subtype, but is also present in other TNBC subtypes and may present an opportunity for targeted therapy. We hypothesized that AR+ TNBC critically depend on AR and that AR inhibition will decrease tumor burden in preclinical models of breast cancer. To determine the extent to which AR+ TNBC depend on AR, we inhibited AR activity with the AR antagonist enzalutamide (ENZ) and shRNAs against AR in multiple TNBC subtypes. Treatment with ENZ prevented AR nuclear localization in response to DHT in multiple TNBC cell lines, reduced baseline proliferation in 2D culture (p Citation Format: Valerie N Barton, Nicholas C D9Amato, Michael A Gordon, Britta M Jacobsen, Jennifer K Richer. Multiple subtypes of triple negative breast cancer are dependent on androgen receptor [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-04-02.