We performed drug library screens using the Spectrum and Prestwick drug libraries (consisting of 2320 and 1200 therapeutically diverse but mainly FDA-approved compounds, respectively) at a drug concentration of 1 μM on various MLL-rearranged ALL cell lines as well as non-MLL B-cell precursor (BCP) ALL cell lines. Here, KMT2A is linked to acute lymphoblastic leukemia.