It was thought to be a lifesaver, but now there’s evidence that a compound widely used for fighting tumors may actually be making a deadly aggressive form of cancer worse. A protein called RUNX1 is a transcription factor, which helps control which genes are active at a given time. Ordinarily, RUNX1 shrinks and suppresses tumors, particularly in a treatment-resistant type of leukemia called T-cell acute lymphoblastic leukemia. However researchers found that blocking its activity is what is needed to help fight a different form, acute myeloid leukemia. Acute myeloid leukemia is not unusually resistant to treatment, but it does move quickly; patients must receive chemotherapy, radiation or bone marrow transplant right away, and these treatments are not always effective.
Acute myeloid leukemia is the most common form of leukemia in adults, though it is a rare condition overall. It accounts for about one in 80 cancer deaths in the United States. Risk of AML goes up with age and the condition is more common in men than in women. The exact cause is unknown, but chemical exposure is believed to be a factor in some cases. People who have a family history of leukemia or who have had other forms of cancer or other blood disorders are likely to get acute myeloid leukemia as well. Smoking increases the risk of AML directly as well as that of those precursor conditions.
Treatment for AML generally means first killing the active cancer, to cause the patient to go into remission, and then destroying the remaining cells to prevent relapse. Chemotherapy is generally used to bring about remission, and then a bone marrow transplant is used to remove the rest of the cancer cells. The availability of bone marrow transplantation procedures makes it possible for doctors to completely destroy bone marrow that is producing damaged cells, and replace it with bone marrow producing healthy cells.
Blocking the activity of RUNX1 may be an emerging treatment approach in the future. When an experimental molecule that blocks the protein was administered to experimental animals, it stopped the leukemia cells from developing, the opposite result of what researchers expected.