PROM1 and chronic myelogenous leukemia, BCR-ABL1 positive: In view of our finding that CD133 is downregulated in CML CD34+ G0 cells compared to normal CD34+ G0 cells, it is of particular interest that the authors suggested that its downregulation in aggressive colonic cancer may indicate transformation of primary CD133+ cancer cells into more malignant CD133− metastatic tumors [52].