ESR1 and breast cancer: ZEB1, a master EMT inducer, is upregulated in breast cancer, contributing to metastasis and drug resistance.[43, 44] ZEB1 confers resistance to endocrine therapy by inducing ERα promoter hypermethylation.[45] We also demonstrated that ZEB1 interplayed with HDAC1/2 and DNMT3B at the MIR497HG promoter, resulting in promoter hypermethylation and histone deacetylation, which can be reversed by ZEB1 depletion.