Pancreatic cancer cells can “starve” thanks to a combination of a new type of cancer drug and a keto diet, an early study suggests.
Researchers said that their new study points to a “vulnerability” which could potentially lead to a new treatment for pancreatic cancer, which has notoriously poor outcomes.
Only around 5% of people with the disease survive for a decade after diagnosis.
Pancreatic Cancer UK urged patients not to make any radical changes to their diets, saying that the study was still in the early stages and the drug has not yet been tested in humans with pancreatic cancer.
Researchers initially set out to examine how the body manages to support itself on fat while fasting.
They found that a protein known as eukaryotic translation initiation factor (eIF4E) changes the body’s metabolism to switch to “fat consumption” during fasting.
The same switch also occurs when an animal is on a ketogenic diet – a diet based on high fat and low carbohydrates.
The team, from UC San Francisco in the US, discovered that a new cancer drug called eFT508, which is currently in clinical trials, blocked this protein, preventing the body from metabolising fat.
In mouse studies, researchers found that when cancer therapy blocks fat metabolism, which is the tumour’s only source of fuel for as long as the mice remain on the ketogenic diet, the cancer appeared to stop growing.
“Certain cancers can use ketone bodies as an alternative energy source to sustain cancer fitness, such as pancreatic tumours,” they wrote in the journal Nature.
Professor Davide Ruggero, senior author of the paper, said: “Our findings led us straight to the biology of one of the deadliest cancers, pancreatic cancer.”
Knowing that pancreatic cancer can thrive on fat, and that the eIF4E protein is more active during fat burning, the scientists first placed the animals on a ketogenic diet, forcing the tumours to consume fats alone, and then put them on the cancer drug.
Researchers said this meant that the drug cut off the cancer cells’ only sustenance – and the cancer appeared to shrink.
Prof Ruggero added: “Our findings open a point of vulnerability that we can treat with a clinical inhibitor that we already know is safe in humans.
“We now have firm evidence of one way in which diet might be used alongside pre-existing cancer therapies to precisely eliminate a cancer.”
He continued: “We expect most cancers to have other vulnerabilities.
“This is the foundation for a new way to treat cancer with diet and personalised therapies.”
Dr Chris Macdonald, head of research at Pancreatic Cancer UK, said: “Pancreatic cancer is the deadliest common cancer.
“Over half of people diagnosed die within three months. In order to improve survival rates, we desperately need new ways to diagnose and treat this devastating disease.
“Understanding how cancer cells are able to grow and spread so rapidly, and the ways in which this is fuelled, is a key area of research that could lead to new and more effective treatments.
“However, this new study is early-stage research of a drug that has not yet been used in the context of pancreatic cancer in humans, as the research was carried out in mice, so we must treat these results with caution.
“People with pancreatic cancer suffer considerably from malnutrition and inability to digest food as a result of their cancer.
“Based on the current evidence, we would strongly advise that people with pancreatic cancer do not make any radical changes to their diet unless advised by a medical professional.”
