ESR1 and breast cancer: Mostafa et al. (2014) showed that estradiol (E2), ERα‐triggered signaling, and estrogen analogs such as tamoxifen and phytoestrogens regulated the production of IFN‐γ in ER+ (MCF‐7 and BT‐474) and even ER− (SK‐BR‐3 and MDA‐MB‐231) BC cell lines (Mostafa et al., 2014).