In a second study in the same journal, researchers from Washington University School of Medicine in St. Louis used DNA sequencing technology to map a series of mutations that transformed myelodysplastic syndrome into leukemia in seven patients.
Myelodysplastic syndrome occurs when blood cells produced in the bone marrow don't fully develop and immature cells crowd out healthy ones. Some patients can be treated with blood transfusions, but about one-third progress to acute myeloid leukemia, according to background information in the study.
In the study, researchers sequenced tumor cells from patients who had myelodysplastic syndrome, and then again later on, when disease had progressed to leukemia. They found that cancer cells evolved over time, gaining new mutations but also retaining certain mutations that likely first turned healthy cells into cancerous cells.
Drugs that target those original mutations that are present throughout the cancer would probably be most effective, the researchers said.
Researchers said to think of cancer as a tree.
"To kill a tree, you have to pull out the roots," senior study author Dr. Timothy Graubert said in a university news release. "If you only cut off a limb, it will just grow back. We're saying that to be effective, targeted cancer drugs probably need to attack mutations at the root of this disease."
The U.S. National Cancer Institute has more on acute myeloid leukemia.
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