Its structural analog vorinostat (SAHA) is a pan-inhibitor of classical classes of HDACs (I, II, and IV) and was approved in October 2006 for the treatment of cutaneous T-cell lymphoma (CTCL) (Table 4).446 Belinostat and panobinostat are two other hydroxamate pan-HDAC inhibitors that are approved for the treatment of relapsed or refractory peripheral T-cell lymphomas (PTCL) and drug-resistant MM, respectively.447,448 Both of them are derivatives of M-carboxycinnamic acid bishydroxamate. Here, HDAC9 is linked to primary cutaneous T-cell non-Hodgkin lymphoma.