BRD9 and breast cancer: As presented in Figure 2E, several BrD members, namely BRPF1, SMARCA4, BRD7, BRD9, BAZ1B, ATAD2 and BRD4 are significantly upregulated in basal breast cancer subtype (when compared to less aggressive luminal A and normal‐like subtype), which strongly mimics the results obtained for the mRNA‐SI (Table S5).