These include 5-azacytidine (1, DNMT inhibitor approved for the treatment of MDS) [66], 5-Aza-2-deoxycytidine (2, DNMT inhibitor approved for the treatment of MDS) [66], FK-228 (3, HDAC inhibitor approved for the treatment of refractory CTCL) [67], SAHA (4, HDAC inhibitor approved for the treatment of refractory CTCL) [68], PXD101 (5, HDAC inhibitor approved for the treatment of refractory PTCL) [69], LBH589 (6, HDAC inhibitor for the treatment of multiple myeloma) [70] and tazemetostat (7, EZH2 inhibitor approved for the treatment of metastatic or locally advanced epithelioid sarcoma) [71]. This evidence concerns the gene HDAC9 and plasma cell myeloma.