¹Department of Hematology, University Medical Center Nijmegen 'St. Radboud', Nijmegen Center for Molecular Life Sciences, Nijmegen, The Netherlands

Correspondence: Dr MHGP Raaijmakers, Center for Regenerative Medicine, Massachusetts General Hospital, Harvard Stem Cell Institute, Harvard Medical School, 185 Cambridge Street, CPZN-4265A, Boston, MA 02114-2790, USA. E-mail: hraaijmakers@partners.org

Received 12 June 2007; Accepted 14 June 2007; Published online 26 July 2007.

Abstract

ATP-binding-cassette (ABC) transporters are evolutionary extremely well-conserved transmembrane proteins that are highly expressed in hematopoietic stem cells (HSCs). The physiological function in human stem cells is believed to be protection against genetic damage caused by both environmental and naturally occurring xenobiotics. Additionally, ABC transporters have been implicated in the maintenance of quiescence and cell fate decisions of stem cells. These physiological roles suggest a potential role in the pathogenesis and biology of stem cell-derived hematological malignancies such as acute and chronic myeloid leukemia. This paper reviews the (patho)physiological role of ABC transporters in human normal and malignant HSCs and discusses its implications for their utility as therapeutical targets to eradicate leukemic stem cells in these diseases.