HDAC9 and diffuse large B-cell lymphoma: We treated the refractory DLBCL cells, Karpas-422 and SUDHL4, with 2μM ACY-957, 2μM ACY-1044 (the HDAC3 inhibitor) or 2μM Vorinostat (SAHA, a pan HDAC inhibitor that targets HDAC1,2 and HDAC3).