Moreover, Snail is directly transcriptional repressed by MTA3[18] and ZEB2 represses MTA3 expression through the formation of a ZEB2/G9A/NuRD(MTA1) complex.[20] Evidently, a reciprocal feedback regulatory loop exists during breast cancer progression in which loss‐of‐function of ERα and GATA3 leads to elevated expression of CUL4B and MTA1. This evidence concerns the gene CUL4B and breast cancer.