The expression of BMI-1, an epigenetic repressor of the CDKN2A tumor suppressor locus and regulator of human HSC self-renewal [17], is higher in CD34+ cells from patients with CML than in those from healthy donors, and also increases with disease progression from chronic to advanced phase [79]. Here, CD34 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.