Glioblastoma, the most aggressive form of brain cancer, is notoriously difficult to treat. Surgery, radiation and chemotherapy can slow tumor growth, but the cancer almost always returns.
Now, researchers at the University of Michigan report that changes in diet may one day offer patients another tool, though for now, the findings are limited to mouse studies.
The study, published in Nature and supported by multiple U.S. National Institutes of Health grants as well as cancer foundations, also comes with conflict-of-interest disclosures. Several of the researchers hold patents or consulting roles related to brain tumor treatment. The authors note these interests but emphasize that the work is still at an early stage and has not yet been tested in clinical trials.
The research team tracked how glucose, the simple sugar that fuels cells, was used in brain tumors compared with healthy brain tissue. Normal brain cells relied on sugar for energy and neurotransmitter production. Tumor cells, by contrast, rerouted sugar into building blocks for new cancer cells, helping them grow and spread.
“It’s a metabolic fork in the road,” said study co-author Andrew Scott, PhD. “The brain channels sugar into energy production and neurotransmitters for thinking and health, but tumors redirect sugar to make materials for more cancer cells.”
The scientists also found that while healthy brain tissue used sugar to make certain amino acids (the building blocks of proteins), tumors shut down that process and instead scavenged amino acids from the blood. That insight led them to test whether reducing the availability of specific amino acids could weaken the tumors.
When mice were fed diets lacking the amino acids serine and glycine, their brain tumors grew more slowly, and they responded better to radiation and chemotherapy, compared with mice on a standard diet.
“Our study may help create new treatment opportunities for patients in the near future,” said co-senior author Daniel Wahl, MD, PhD, associate professor of radiation oncology.
The team is now developing clinical trials to test whether carefully designed diets could enhance standard care in people with glioblastoma.
This study was funded by the National Cancer Institute, the National Institute of Neurological Disorders and Stroke, the National Institute of Diabetes and Digestive and Kidney Diseases, the National Institute of General Medical Sciences and several cancer foundations, including Damon Runyon, Sontag, Ivy Glioblastoma Foundation, Alex’s Lemonade Stand Foundation and the Chad Tough Defeat DIPG Foundation.
Several authors reported consulting roles with pharmaceutical companies and patents related to brain tumor therapies.