Chronic myeloid leukemia stem cells and molecular target therapies for overcoming resistance and disease persistence.

Chronic myeloid leukemia (CML) is effectively treated with tyrosine kinase inhibitors (TKI) targeted against BCR-ABL. We previously reported the investigation of residual CML diseases during TKI treatment using FACS-sorting and quantitative RT-PCR of BCR-ABL among each population; total mononuclear cells, hematopoietic stem cells, and myeloid progenitors. The observations also implied that the second-generation of ABL-tyrosine kinase inhibitors (2nd TKIs), dasatinib or nilotinib therapy can be more promising approach for efficient reduction of the CML stem cells. Moreover, we need to develop the evaluation method of the residual CML diseases to establish rational therapy-cessation strategies in CML.