KMT2A and acute lymphoblastic leukemia: However, NSG mice engrafted with MLL-ALL derived from Patient 11 showed the most remaining leukaemia cells after combination treatment, in PB (Fig. 3a), BM and spleen (Fig. 3c and d) compared to the recipients engrafted with the other five cases indicating that leukemic cells of Patient 11 are resitant even to the combination treatment.