Metformin, a widely used and affordable drug for type 2 diabetes, could help prevent a deadly form of blood cancer known as acute myeloid leukemia (AML) in people at high risk, according to a new study in mice. The findings, published in Nature, open the door to using an already-approved and safe medication as a possible way to stop AML before it develops.
Each year, around 3,100 people in the UK are diagnosed with AML. It is an aggressive cancer that affects the blood and bone marrow and is very hard to treat. Even with improvements in care, long-term survival is low—only about 20% of patients live five years or more after diagnosis.
Fortunately, scientists have developed ways to detect people at risk of AML years before the disease appears. By analyzing blood samples and DNA, doctors can now identify individuals whose blood stem cells carry specific mutations that may lead to AML.
However, there is currently no treatment to stop these early-stage changes from progressing into full-blown leukemia.
This study, led by Professor George Vassiliou and a team at the University of Cambridge, focused on a common genetic change that increases AML risk. This mutation affects a gene called DNMT3A, which is responsible for 10–15% of all AML cases. The researchers wanted to find a way to stop these mutated blood cells from growing before they turn cancerous.
Using mice with the same DNMT3A mutation found in humans, the researchers discovered that the pre-cancerous cells rely heavily on mitochondrial metabolism—a process where cells generate energy. This difference gave the team an idea: what if they could use a drug that targets this energy source?
That’s where metformin comes in. Metformin affects how cells use their mitochondria to produce energy. When given to the mice, it slowed the growth of the harmful blood cells and prevented them from taking over the healthy blood system. Even more encouraging, metformin appeared to reverse some of the effects caused by the DNMT3A mutation.
The scientists also tested human blood cells with the same mutation and saw similar results. Metformin reduced the cells’ ability to grow and become more dangerous, suggesting that this approach could work in people too.
To back up their lab results, the researchers looked at data from more than 412,000 people in the UK Biobank. They found that people who were taking metformin were less likely to have the DNMT3A mutation in their blood, even when accounting for other factors like diabetes and body weight.
This supports the idea that metformin could help protect against the development of AML.
Professor Brian Huntly, co-lead of the study, emphasized how important the drug’s specificity is. Rather than acting as a general cancer prevention tool, metformin seems to work especially well against this particular mutation. That means it could one day be used to target high-risk patients more precisely, without affecting healthy cells.
Another major advantage of metformin is that it’s already widely used and has a long track record of safety. This could make it faster and easier to move into clinical trials, without the delays involved in developing brand-new drugs from scratch.
Dr. Rubina Ahmed of Blood Cancer UK noted how urgent the need is for better AML treatments. With survival rates still low, finding a way to stop the disease before it begins could save many lives. Repurposing existing drugs like metformin, she said, offers a promising shortcut to get effective treatments to patients sooner.
The next step for the research team is to begin human clinical trials. They will focus on people who have the DNMT3A mutation and are known to be at higher risk of AML. If successful, this approach could mark a major shift in how doctors deal with blood cancer—not just treating it after it appears, but preventing it altogether.
Tanya Hollands from Cancer Research UK added that although these early results are promising, more work is needed to confirm the findings in people. Still, she called the study “a positive step” toward protecting those at risk.
In short, this research suggests that metformin could offer a safe, simple, and cost-effective way to prevent one of the deadliest forms of blood cancer—potentially changing the future for thousands of people worldwide.
If you care about diabetes, please read studies about a cure for type 2 diabetes, and these vegetables could protect against kidney damage in diabetes.
For more information about diabetes, please see recent studies about bone drug that could lower risk of type 2 diabetes, and results showing eating more eggs linked to higher risk of type 2 diabetes.
The research findings can be found in Nature.
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