最近看了电影《左右》，其中小女孩得的白雪病，让两个家庭非常痛苦，今看到关于白血病的惊喜报道，很高兴，现转载

Monterotondo, 8 April 2008 - Leukaemia cancer of blood orbone marrow -is caused by mutations that allow defectiveblood cells to accumulate and displace healthy blood. Todevise effective therapies it is crucial to know which mutationscause leukaemia and which cell type gives rise to leukaemiccells. Researchers from the European Molecular BiologyLaboratory (EMBL) in Italy, the EMBL-EuropeanBioinformatics Institute, UK, and the Universities of Harvard,USA, and Lund, Sweden, have now used genetic engineeringto introduce a mutation found in human leukaemia patientsinto mice. In the current issue of Cancer Cell they report thatthe mutation causes leukaemia by triggering innate geneticprogrammes that allow white blood cells to proliferate uncontrollably.The findings have implications for the wayleukaemia should be treated.Blood is generated from a small number of multipotent stemcells that divide, differentiate and give rise to the many differentcell types that make up the blood. At the same time theyalso maintain the pool of stem cells through a process called
self-renewal. While differentiating, cells acquire specific propertiesand functions, but lose the capacity to self-renew in theway stem cells do. Mutations interfering with this process andpromoting uncontrolled proliferation of certain blood cellscan lead to leukaemia. Researchers of the group of ClausNerlov at EMBL抯 Mouse Biology Unit now prove that a mutationin a protein called C/EBPa causes acute myeloidleukaemia (AML), a type of leukaemia affecting one lineage ofwhite blood cells, in mice.?0 percent of all patients suffering from AML have this mutation,but we could never be sure if it causes the disease. By preciselyreproducing the human mutation in the mouse we nowproved a causative relation,?says Peggy Kirstetter, who carried
out the research in Nerlov抯 lab.Instead of promoting uncontrolled proliferation of malignantblood stem cells, as often assumed as the cause of leukaemia,the mutation acts on already partially differentiated cells. It
reprogrammes these cells to self-renew and to produce countlessdysfunctional daughter cells, which displace the healthyblood cells, eventually leading to the inability to transport oxygen
around in the body.this is the first time that non-stem cell myeloid leukaemiahas been generated within a healthy blood system. The findingswill have profound implications for our understanding of
the development and treatment of leukaemias,?says Nerlov.Scientists always thought that the mutation was the crucialstep leading to leukaemia that should be targeted by drugs.Nerlov and colleagues identified a genetic programme activatedin self-renewing leukemic cells, which is shared with similar
leukaemias caused by other types of mutations. The findingssuggest that the cellular changes that lead to self-renewalare mutation-independent. To develop drugs with a moregeneral efficacy it may therefore be more efficient to target themolecules and pathways shared between different cancer stemcells.
An unexpected way to cause leukaemia
New mouse model grants insight into the genetic and molecular mechanisms
underpinning acute myeloid leukaemia

Source Article
P. Kirstetter, M.B. Schuster, O. Bereshchenko. S. Moore, H. Dvinge, E. Kurz, K. Theilgaard-Mönch, R. Månsson, T.Å. Pedersen, T.
Pabst, E. Schrock, B.T. Porse, S.E.W. Jacobsen, P. Bertone, D.G. Tenen & C. Nerlov. Modeling of C/EBPa mutant acute myeloid
leukemia reveals a common expression signature of committed myeloid leukemia initiating cells. Cancer Cell, 8 April 2008