When comparing therapy-naïve, wtKLF4-expressing cells (Fig. 4b) with similar cells obtained after chemotherapy in MRD (Fig. 4d, lower right panel), KLF4 inhibited the growth of MRD cells more dramatically than that of therapy-naïve PDX B-ALL cells (Supplementary Figure S9). The gene discussed is KLF4; the disease is acute lymphoblastic leukemia.