ZEB1 represses Ngn3 transcription by recruiting DNA methyltransferase (DNMT)3B and histone deacetylase (HDAC)1 to the Ngn3 promoter, thus resulting in DNA hypermethylation and the silencing of Ngn3. We also demonstrated an inverse correlation between ZEB1 and NGN3 expression in human breast cancer specimens. This evidence concerns the gene ZEB1 and breast cancer.