HDAC9 and mature T-cell and NK-cell non-Hodgkin lymphoma: The pan HDAC inhibitor belinostat was FDA-approved for the treatment of PTCL in 2014 [139], and the pan HDAC inhibitor panobinostat gained accelerated approval in 2015 to treat multiple myeloma in combination with dexamethasone and the proteasome inhibitor bortezomib [140].