There is the problem of identifying the Leukeic sem cells from healthy sc and then there is the problem of getting the stem cells to leave their niche in the bone marrow. CML is the model for studying this problem as when the tyrosine kinase inhibitor is removed the disease returns. Here is a nice review article on approachs to getting those lcs to leave their home.
Perspectives
Nature Reviews Immunology 10, 201-209 (March 2010) | doi:10.1038/nri2726
Opinion: Awakening dormant haematopoietic stem cells
Andreas Trumpp1, Marieke Essers & Anne Wilson
Abstract
Haematopoietic stem cells (HSCs) in mouse bone marrow are located in specialized niches as single cells. During homeostasis, signals from this environment keep some HSCs dormant, which preserves long-term self-renewal potential, while other HSCs actively self renew to maintain haematopoiesis. In response to haematopoietic stress, dormant HSCs become activated and rapidly replenish the haematopoietic system. Interestingly, three factors — granulocyte colony-stimulating factor, interferon-? and arsenic trioxide — have been shown to efficiently activate dormant stem cells and thereby could break their resistance to anti-proliferative chemotherapeutics. Thus, we propose that two-step strategies could target resistant leukaemic stem cells by priming tumours with activators of dormancy followed by chemotherapy or targeted therapies.