HDAC9 and lymphoma: Given the important roles of HDAC and DOT1L in lymphocytes (Haery et al., 2015; Ellmeier and Seiser, 2018; Kealy et al., 2020; Kwesi-Maliepaard et al., 2020; Scheer et al., 2020; Aslam et al., 2021; Wille and Sridharan, 2022) it would certainly be interesting the assess the effect of HDAC inhibitors in combination with DOT1L inhibitors on normal immune cells and in other types of lymphoma.