Affiliation:
1. Laboratory of Integrative Oncology National Cancer Center Research Institute Tokyo Japan
2. Department of Life Science and Medical Bioscience, School of Advanced Science and Engineering Waseda University Tokyo Japan
3. Department of Urology The Jikei University School of Medicine Tokyo Japan
4. Translational Research Center Fukushima Medical University Fukushima Japan
Abstract
AbstractAntiandrogens were originally developed as therapeutic agents for prostate cancer but are also expected to be effective for breast cancer. However, the role of androgen signaling in breast cancer has long been controversial due to the limited number of experimental models. Our study aimed to comprehensively investigate the efficacy of antiandrogens on breast cancer. In the present study, a total of 18 breast cancer cell lines were treated with the agonist or antagonists of the androgen receptor (AR). Among the 18 cell lines tested, only T‐47D cells proliferated in an androgen‐dependent manner, while the other cell lines were almost irresponsive to AR stimulation. On the other hand, treatment with AR antagonists at relatively high doses suppressed the proliferation of not only T‐47D cells but also some other cell lines including AR‐low/negative cells. In addition, expression of the full‐length AR and constitutively active AR splice variants, AR‐V7 and ARV567es, was not correlated with sensitivity to AR antagonists. These data suggest that the antiproliferative effect of AR antagonists is AR‐independent in some cases. Consistently, proliferation of AR‐knockout BT‐549 cells was inhibited by AR antagonists. Identification of biomarkers would be necessary to determine which breast cancer patients will benefit from these drugs.