Leukaemic stem cells: Drug resistance, metastasis and therapeutic implications

Faculty of Medicine, SEGi University, No. 9, Jalan Tecknologi, Taman Sains Selangor, Kota Damansara, PJU 5, 47810 Petaling Jaya, Selangor, Malaysia.
The Malaysian journal of pathology 12/2012; 34(2):77-88.
Source: PubMed


Although there have been many new developments in the treatment of leukaemia with the use of new anti-leukaemic agents and stem cell transplantation, drug resistance and treatment failure remain a great challenge for the attending physician. Several studies have suggested that leukaemic stem cells (LSCs) play a pivotal role in chemoresistance and metastasis and the mechanisms by which these cells do so have also been elucidated. There is increasing evidence to show that there exists a large pool of therapeutic targets in LSCs and that the eradication of these cells is feasible with some promising results. This article gives an overview of different types of cancer stem cells (CSCs) derived from various types of leukaemia, the mechanisms by which LSCs contribute to drug resistance and metastasis and some recent advances in targeted therapy against LSCs.

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    • "Although chemotherapy results in clinical remission for AML, drug resistance still represents a huge challenge to achieve effective treatment, especially in relapsed or refractory AML patients [1], [2]. Cytostatic drug resistance occurs through different mechanisms, including induction of drug detoxification [3], the over-expression of oncogene or inactivation of tumor suppressor gene [4], [5], metabolic disturbance [6], [7], as well as existence of leukemia stem cells [8]. Still, the exact mechanisms of drug resistance in leukemia have not been fully investigated. "
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