Finally, ex vivo treatment of primary patient-derived leukemic cells of different cytogenetic background with lysosomal and Vps34 inhibitors showed that cells from the two ETV6/RUNX1 t(12;21) bearing samples were significantly more sensitive to PIK-III as compared to cells from other pre-B-ALL genetic sub-groups or T-ALL (Fig. 2f and Supplementary Tables 3 and 4 for patient information and DSS scores, respectively). The gene discussed is PIK3C3; the disease is acute lymphoblastic leukemia.