Significantly higher levels of MYB expression also were detected in all CML myeloid blast crisis patients than chronic and accelerated phase cases examined in our study, further suggesting a possibility that abnormal activation of MYB expression could be a major “driver” for CML progression into myeloid blast crisis by conferring self-renewal capability to GMPs. This evidence concerns the gene MYB and chronic myelogenous leukemia, BCR-ABL1 positive.