HDAC9 and angioimmunoblastic T-cell lymphoma: Furthermore, epigenetic modifiers, including histone deacetylase (HDAC) inhibitors (such as romidepsin, belinostat, and chidamide [tucidinostat]) as well as hypomethylating agents (such as azacitidine), are effective against various subtypes of PTCL, particularly nTFHL, angioimmunoblastic type (nTFHL-AI, previously called as angioimmunoblastic T-cell lymphoma [AITL]) (3), (5).