RET expression is also dependent on chromatin structure [39] and histone deacetylase (HDAC) inhibitors, such as Tricostatin A, Sodium Butyrate (Nabut), and 5 aza-2′ deoxycytidine (deAza), have opposite effects on estrogen mediated transcription in BC cell lines, thus affecting anti-estrogen therapy [40]. Here, HDAC9 is linked to breast cancer.