Effectiveness of CUDC-907 in MEF2D fusion cells considerably surpassed that of other non-MEF2D fusion cell lines (IC50 value was 530.3 nM in JM1, 600.1 nM in Nalm6, 486.7 nM in RCH-ACV, 858.7 nM in REH, 465.4 nM in SEM, and 453.2 nM in sup-B15) and therefore exhibited high BCP-ALL targeting selectivity (Fig. 2d, Supplementary Fig. 1d and Supplementary Table 2). The gene discussed is OPN1SW; the disease is acute lymphoblastic leukemia.