Editor's Summary
25 May 2006
Cancer stem cell function
Stem cells that initiate and maintain cancers are so like normal stem cells that it's hard to design drugs to target them specifically. This is a serious problem as, for example, damaging blood stem cells in leukaemia therapy can cause haematopoietic failure and death. Now a study of the tumour suppressor PTEN, often inactivated in leukaemia and other cancers, pinpoints a major difference between self-renewal in normal and cancer stem cells. PTEN normally inhibits the phosphatidylinositol-3-OH kinase signalling pathway, limiting cell proliferation and survival. In the absence of PTEN, leukaemic stem cells proliferate, but normal stem cells are depleted. This suggests that PTEN-mimicking drugs may act against leukaemia yet preserve blood stem cells. Indeed, in Pten-deficient mice rapamycin kills leukaemic stem cells but rescues normal stem cell function. A separate study confirms PTEN's role in blood stem cell regulation.
News and Views: Materials science: Film review
Maria Bellantone
doi:10.1038/441418a
Article: Pten dependence distinguishes haematopoietic stem cells from leukaemia-initiating cells
Ömer H. Yilmaz, Riccardo Valdez, Brian K. Theisen, Wei Guo, David O. Ferguson, Hong Wu and Sean J. Morrison
doi:10.1038/nature04703
Abstract | Full Text | PDF (989K) | Supplementary information
Letter: PTEN maintains haematopoietic stem cells and acts in lineage choice and leukaemia prevention
Jiwang Zhang, Justin C. Grindley, Tong Yin, Sachintha Jayasinghe, Xi C. He, Jason T. Ross, Jeffrey S. Haug, Dawn Rupp, Kimberly S. Porter-Westpfahl, Leanne M. Wiedemann, Hong Wu and Linheng Li
doi:10.1038/nature04747
First paragraph | Full Text | PDF (589K) | Supplementary information
