Evaluating an Esr1-mutant novel cell population emerging upon ERα-antagonism by single RNA-seq

To examine the effects of ERα antagonism (giredestrant) on Esr1-wildtype and Esr1-mutant mammary glands, animals were treated with hormone pellets (E2, P4), then dosed daily with vehicle (MCT) or giredestrant (30 mg/kg, p.o.) for four days. Following dosing, EpCAM+ cells were isolated and used for single cell sequencing. For each condition, cells from 2 animals were pooled for sequencing. Esr1-wildtype and Esr1-mutant mammary glands, animals were treated with hormone pellets (E2, P4), then dosed daily with vehicle (MCT) or giredestrant. 4 samples are included.