Protein Suppression Stops Leukemia Growth in Mice

Leukemia causing stem cells have been eliminated in mice by suppressing two proteins. Cancer stem cells are thought to be responsible for relapses in leukemia. The findings could lead to new treatments to prevent this. Researchers bred GM mice that didn't producing two naturally occurring proteins, called Bmi1 and Hoxa9. The lack of these proteins stopped leukemia developing in the mice. The findings apply to a type of leukemia that involved the mutation of a gene called MLL. This accounts for seven in ten cases of childhood leukemia. Only half of children diagnosed with MLL leukemia survive more than two years when given standard treatments. The protein Bmi1 was already known to be important for the survival of cancer stem cells. But targeting this protein on its own is not enough to eradicate MLL leukemia causing stem cells. By suppressing the protein Hoxa9 as well, the MLL mutation is unable to cause leukemia. Targeting these proteins together could lead to treatments for MLL leukemia. Researchers hope the findings will also help them understand the process by which leukemia cells originate - Cell Stem Cell, DOI: 10.1016/j.stem.2011.05.004, 3 Jun 11