Exercise can boost the effectiveness of cancer drugs and increase survival rates, a study suggests.
Scientists have found that proteins released by the body to help repair muscles worn by exercise also attack cancer cells.
After proving their theory in mice, they analyzed data from a human trial of 75 patients with pancreatic cancer.
One group was asked to do one hour of strength exercise and 90 minutes per week of aerobic exercise before having surgery to remove their tumors.
Those who followed the six-week training program have a five-year overall survival rate that was 50 percent higher than those who did not follow the regimen.
Scientists have long promoted the benefits of exercise in terms of reducing people’s risk of developing cancer, but this study suggests that it could also help people with the disease.
Scientists have found that people and mice with pancreatic cancer who are put on an exercise regimen are better able to fight the disease (stock image)
Researchers at the NYU Grossman School of Medicine in New York found that making mice with cancer for 30 minutes five times a week reduced the rate of cancer formation by 50%.
Another test that saw mice running regularly on a treadmill for three weeks reduced the weight of the tumor by 25%.
It was found that induction of adrenaline through exercise stimulated the body to produce more than one protein called interleukin-15.
This in turn increases the capacity of CD8 T cells, a cell in the immune system, which attacks and kills pancreatic cancer cells.
WHAT IS PANCREATIC CANCER?
Pancreatic cancer is one of the deadliest forms of the disease, and about 95% of people who get it die from it.
Joan Crawford, Patrick Swayze and Luciano Pavarotti all died of pancreatic cancer.
It is the sixth leading cause of cancer death in the UK: around 10,000 people are diagnosed with pancreatic cancer each year in the UK, along with around 55,000 in the US.
WHAT IS THE CAUSE?
It is caused by the abnormal and uncontrolled growth of cells in the pancreas, a large gland in the digestive system.
WHO HAS THE GREATEST RISK?
Most cases (90%) are found in people over 55 years of age.
About half of all new cases occur in people 75 years of age or older.
One in 10 cases is attributed to genetics.
Other possible causes include age, smoking, and other health problems, including diabetes.
WHY IS IT SO LETHAL?
There is no screening method for pancreatic cancer.
Pancreatic cancer usually shows no symptoms in the early stages, when it would be more manageable.
People who suffer from it tend to start developing the telltale signs (jaundice and abdominal pain) around stage 3 or 4, when it has probably already spread to other organs.
WHAT ARE THE TREATMENT OPTIONS?
The only effective treatment is to remove the pancreas.
This is largely ineffective for those whose cancer has spread to other organs.
In these cases, palliative care is recommended to relieve your pain at the end of your life.
The researchers then analyzed the results of a human clinical trial in 2017.
These patients were asked to do strengthening exercises for 30 minutes, which could include resistance bands, weight training, or yoga, twice a week.
They were also told to take a brisk walk for 30 minutes at least three times a week.
They followed the diet for six weeks before undergoing surgery to remove their cancers.
Regular blood tests showed that exercising patients had more CD8 T cells.
And looking at health records, the researchers found that these patients also had 50% higher overall survival rates after five years.
NYU researchers said the results of their study showed for the first time how even small amounts of exercise could help treat pancreatic cancer.
They said this was crucial for pancreatic cancer as it has such limited treatment options.
Scientists hope the discovery will eventually lead to better treatment for people with the disease, which is often detected too late and leaves them with few options.
Dr. Emma Kurz, an oncology expert and lead author of the study, said: “Our findings show, for the first time, how aerobic exercise affects the immune microenvironment of pancreatic tumors.”
“The work helped reveal that activating IL-15 signaling in pancreatic cancer could be an important treatment approach in the future.”
To further test the theory, scientists also tested whether exercise could improve traditional cancer therapies in mice.
By itself, this immunotherapy was found to increase the production of cancer cells by 66 percent.
But the production of cancer-killing cells rose 175 percent when mice exercised.
NYU Grossman professor Dafna Bar-Sagi, an expert in biochemistry and another author of the study, said the results showed the potential exercise it could have for treating pancreatic cancer.
“That even gentle exercise can profoundly alter the tumor environment points to the potential of this approach to treating patients with a devastating disease burden and few options,” he said.
Researchers said they now plan to organize another clinical trial to explore the impact of exercise on patients with pancreatic cancer.
They published their findings in the journal Cancer Cell.
Pancreatic cancer is extremely fatal in part because of the difficulty of detecting and treating it.
About 95 percent of people who hire it die because of it.
Some 9,000 Britons die from pancreatic cancer each year. The figure is around 50,000 in the US.
The best way to cure cancer is surgery to remove the cancerous tissue, but only 10% of people have this option, as it is usually only detected when the tumor has already begun to spread to other parts of the body.
The NHS board states that adults should do at least 150 minutes of moderate-intensity activity a week or 75 minutes of vigorous-intensity activity a week.
They should also do muscle strengthening exercises at least two days a week.