ESR1 and breast cancer: Although AR inhibition in TNBC is radiosensitising [7, 8], as is ER inhibition in ER+ breast cancers with low AR expression [22], these findings further suggest that AR and ER signaling are not converging on a single pathway affecting the radiation response when AR and ER are co-expressed in models of breast cancer, or that there may be additional factors involved in the radiation response in AR+/ER+ breast cancer models.