Forcing leukaemia cells to "grow up" and behave responsibly has been shown to tame the disease in the laboratory.
Scientists hope the discovery will lead to radical new treatments for the blood disease and possibly other kinds of cancer.
A hallmark of all cancer cells is that they are immature, or "undifferentiated". In the new study, researchers genetically reprogrammed leukaemia cells so they grew to resemble ordinary white blood cells.
The US scientists believe the rehabilitated leukaemia cells could end up helping to fight the cancer they were once part of.