A specialized diet could potentially slow the progression of aggressive brain tumors, according to new research from the Feinstein Institutes for Medical Research at Northwell Health. The study, published Tuesday, identified a shared metabolic vulnerability in high-grade gliomas and a rare genetic disorder, GAMT Deficiency.
Gliomas are a category of tumors originating in the brain or spinal cord, varying in growth rate. Some, like oligodendrogliomas, are slow-growing, while others, such as glioblastomas, are highly aggressive.
Researchers found that high-grade gliomas exhibit an uncontrolled growth of supportive cells in the brain. This uncontrolled proliferation is linked to the production of a toxic chemical, guanidinoacetate (GAA), which alters brain activity and fuels tumor expansion. This metabolic flaw is also present in children with GAMT Deficiency, a condition characterized by the body's inability to properly metabolize GAA, leading to seizures and epilepsy.
Scientists tested a dietary approach used to manage GAMT Deficiency on mice with gliomas. The results indicated that this medically supervised diet dramatically slowed tumor growth in the rodents. This diet focuses on restricting specific types of food, rather than general diets like the Mediterranean or ketogenic approaches.
"The diet that we are considering for this trial is not really, say, a Mediterranean diet or a ketogenic diet," said Dr. Kalil Abdullah, director for central nervous system cancer at Northwell Health’s Brain Tumor Center. "It’s a diet under medical supervision that restricts very specific types of food."
The study's findings suggest that GAA production can be modulated. The research team observed that by turning off the enzyme (AGAT) responsible for GAA synthesis in tumor cells and adjusting the intake of specific amino acids—restricting arginine and adding ornithine—tumor growth was inhibited in the animal models.
Amino acids, the fundamental components of protein, are naturally present in foods such as meat, eggs, and grains.
Dr. Abdullah explained that initial analysis of tumor tissue samples revealed significantly higher levels of GAA in glioblastomas compared to other brain tumors or healthy brain tissue. This discovery spurred the investigation into the underlying reasons for this elevated presence.
The research team is planning to launch a clinical trial in 2027 to further investigate these findings in human patients. Abdullah noted that preliminary human trials might involve dietary changes for a short period, such as three to five days, before surgery. This would allow researchers to measure GAA levels and assess the diet's impact.
"Because the human body adapts so quickly, we can have patients change their diet for just three to five days before surgery," Abdullah stated. "And then we’ll be able to do the surgery as planned, but we’ll be able to measure this molecule and see if the diet has already made a difference."