ESR1 and breast cancer: In the present study, we showed that arantho EO, which belongs to the Rutaceae family, had time- and concentration-selective cytotoxic activity against MDA-MB-231, a highly invasive estrogen receptor-negative breast cancer cell line, with an IC50 value of 53.81 μg/mL, and possessed better effects than the different extracts of D. bicolor, while no effect was observed using aqueous extract.