HDAC9 and cancer: Moreover, the class I/II HDAC inhibitors vorinostat and entinostat demonstrate preclinical efficacy in repressing EMT in TNBC cell culture models; testing vorinostat or entinostat in in vivo models of TNBC in combination with chemotherapy may demonstrate greater treatment efficacy, as it has been shown in other cancers that chemo-sensitivity significantly increases with tumor differentiation [172,173].