ESR1 and breast carcinoma: ER+ breast cancer cell MCF7 and T47D, and ER− breast cancer cell MDA-MB-231 were irradiated with X-rays at different doses, and we found that 24 h after irradiation, MCF7 and MDA-MB-231 cells expansion and proliferation slowed commensurate with the increase in radiation dose (Fig. 1A).