BMI1 and chronic myelogenous leukemia, BCR-ABL1 positive: Sporadic reports indicate the aberrant expression and deregulation of Twist1 in myeloid neoplasms, including myelodysplastic syndrome and chronic myeloid leukemia.32, 33 Knowing that Bmi1 expression is essential for maintenance and self-renewal of leukemic stem and progenitor cells, we speculate that Twist1 might govern the pathogenesis of development of AML as well.