identified the interplay of ER and GPER in extra-nuclear ER actions via the pharmacological approach towards human breast cancer cell lines T47D and MDA-MB-231 (84), which was in concert with the previously reported clinicopathological evidence that correlated ER and GPER expression in breast cancer either in a positive (85, 86) or a negative way (87, 88). The gene discussed is ESR1; the disease is breast carcinoma.