Supplementary Figure S2 from Palazestrant (OP-1250), A Complete Estrogen Receptor Antagonist, Inhibits Wild-type and Mutant ER-positive Breast Cancer Models as Monotherapy and in Combination

Effects of E2 and antiestrogens on transcriptional activity and cellular proliferation in E2-depleted media. A, Volcano plot of genes differentially expressed by 15-min E2 treatment relative to vehicle in PRO-seq experiment. Each dot represents a gene in the annotation set. Adjusted p-value is plotted on the y-axis and fold-change relative to time-matched vehicle on the x-axis. The number in the top right-hand corner represents the number of genes changed, and red dots indicate genes with observed change in expression. B, PRO-seq read distribution at estrogen target genes CCND1 and MYC after 15 min of E2 treatment (red) compared to vehicle control (blue). The x-axis refers to the position along the genome, and the y-axis refers to the number of reads aligning to that position normalized for the depth of each sample. Replicates were averaged. Bars that are less than zero are reverse-strand reads; bars above zero are forward-strand reads. C, PRO-seq read distribution at estrogen target gene GREB1 after 6 h of OP-1250 treatment following E2 pretreatment (red) compared to 24-h E2 treatment (blue). The x-axis refers to the position along the genome, and the y-axis refers to the number of reads aligning to that position normalized for the depth of each sample. Replicates were averaged. Bars that are less than zero are reverse-strand reads; bars above zero are forward-strand reads. D, Heatmap of annotated G2/M checkpoint genes in CAMA-1 and MCF7 cells after 24 h of compound treatment in PRO-seq experiment. Red indicates high expression and blue low expression. Samples and genes with similar expression patterns are grouped together using hierarchical clustering, with sample relationships depicted by dendrograms at the top and left of graph. E, Chart showing number of differentially expressed genes compared to vehicle for each treatment group in CAMA-1 mRNA-seq experiment. Cells were treated with 100 pM E2 or 316 nM antiestrogen in E2-depleted media for 24 h.