Primary, patient-derived leukemic cells are sensitive to CBX7 inhibition whereas normal primitive CB-derived CD34⁺ cells are insensitive. Percentage of viable immature (CD45dim) AML or CD34⁺ CB cells normalized to their experimental DMSO control after 1 week of in vitro treatment with MS452 (left panel), EC-134 (middle panel), or BDA-41 (right panel). Cells were cultured in StemSpan supplemented with SCF, TPO, and FLT3L. Box plots represent the median of ≥4 different AML or CB samples. Student t test was used to calculate the P value between the AML and CB samples, ∗P < .05.