Figure 6 from ESR1 F404 Mutations and Acquired Resistance to Fulvestrant in ESR1-Mutant Breast Cancer

Compound F404 mutations are sensitive to novel SERDs. A–D, Compound mutations of D538G-F404L in MCF7 cells, along with single mutations and wild-type, with sensitivity to elacestrant (A), camizestrant (B), 4OH tamoxifen (C), and giredestrant (D), assessed after 6 days treatment with CellTiter Glo viability assay. n = 4 mean with SD. E, Representative clonongenic assays grown in indicated concentrations of elacestrant, camizestrant, 4OH tamoxifen, and giredestrant for 14 days. F, MCF7 cells were cotransfected with the indicated ESR1 expression constructs ERE-luciferase reporter and control construct. Cells were treated with indicated concentrations of fulvestrant, elacestrant, camizestrant, 4OH tamoxifen, and giredestrant in the presence of 1 nmol/L estradiol for 24 hours, and ERE-luciferase activity was assessed. Two-way repeated-measures ANOVA with Sidak multiple comparisons test, n = 3 mean with SD; *, P < 0.05.