Exercise can amplify the effectiveness of cancer drugs and boost survival rates, a study suggests.
Scientists found proteins released by the body to help repair muscles worn out from exercise also attack cancer cells.
After proving their theory in mice, they analysed data from a human trial of 75 patients with pancreatic cancer.
One group was asked to do an hour of strength-training exercise and 90 minutes per of aerobic exercise per week before they had surgery to remove their tumours.
Those who followed the six-week training programme has an overall five-year survival rate that was 50 per cent higher than those who did not follow the regime.
Scientist have long touted the benefits of exercise in terms of reducing people’s risk of developing cancer but this study suggest it could also help people suffering from the disease.
Scientists have found people and mice with pancreatic cancer who are put on an exercise regime are better able to fight off the disease (stock image)
Researchers from NYU Grossman School of Medicine, in New York, found making mice with cancer exercise for 30 minutes five times a week reduced the rate of cancer formation by 50 per cent.
Another test which saw mice regularly run on a treadmill for three weeks reduced tumour weight by 25 per cent.
Inducing adrenaline through exercise was found to stimulate the body to produce more of a protein called interleukin-15.
This in turn increases the ability of CD8 T cells, an immune system cell, which attacks and kills pancreatic cancer cells.
WHAT IS PANCREATIC CANCER?
Pancreatic cancer is one of the most lethal forms of the disease, and around 95 per cent of people who contract it die from it.
Joan Crawford, Patrick Swayze and Luciano Pavarotti all died of pancreatic cancer.
It is the sixth most common cause of cancer death in the UK – around 10,000 people are diagnosed with pancreatic cancer each year in the UK, alongside about 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 HIGHEST RISK?
Most cases (90 per cent) are in people over the age of 55.
Around half of all new cases occur in people aged 75 or older.
One in 10 cases are attributed to genetics.
Other possible causes include age, smoking and other health conditions, including diabetes.
WHY IS IT SO LETHAL?
There is no screening method for pancreatic cancer.
Pancreatic cancer typically does not show symptoms in the early stages, when it would be more manageable.
Sufferers tend to start developing the tell-tale signs – jaundice and abdominal pain – around stage 3 or 4, when it has likely already spread to other organs.
WHAT ARE THE TREATMENT OPTIONS?
The only effective treatment is removal of the pancreas.
This proves largely ineffective for those whose cancer has spread to other organs.
In those cases, palliative care is advised to ease their pain at the end of their life.
Researchers then analysed the results of a clinical trial of humans in 2017.
These patients were asked to perform strengthening exercises for 30 minutes, which could involve resistance bands, weight-training or yoga, two times per week.
They were also told to go on a brisk walk for 30 minutes at least three times a week.
They followed the regime for six weeks before having operations to remove their cancers.
Regular blood tests showed that patients who exercised had more CD8 T cells.
And looking at health records, the researchers found these patients also had 50 per cent higher overall survival rates after five years.
The 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 critical for pancreatic cancer as it has such limited treatment options.
The scientists hope the discovery will eventually lead to better treatment for people with this disease which is often detected too late leaving suffers with few options.
Dr Emma Kurz, an expert in oncology and lead author of the study, said: ‘Our findings show, for the first time, how aerobic exercise affects the immune microenvironment within pancreatic tumours.’
‘The work helped to reveal that activation of IL-15 signalling in pancreatic cancer might be an important treatment approach in the future.’
To further test the theory, the scientists also tested if it exercise could enhance traditional cancer therapies on mice.
By itself, this immunotherapy was found to increase the production of cancer killing cells by 66 per cent.
But cancer killing cell production increased 175 per cent when the mice went on an exercise regime.
NYU Grossman’s Professor Dafna Bar-Sagi, an expert in biochemistry, and another author of the study, said the results showed the potential exercise could have for treatment of pancreatic cancer.
‘That even mild exercise can profoundly alter the environment in tumours points to the potential of this approach in treating patients with a devastating disease burden and few options,’ she said.
The researchers said they are now planning to host another clinical trial exploring the impact of exercise on pancreatic cancer patients.
They published their findings in the journal Cancer Cell.
Pancreatic cancer is extremely deadly in part because of how difficult it is to detect and treat.
Around 95 per cent of people who contract it die from it.
About 9,000 Britons die from pancreatic cancer every year. The figure stands at around 50,000 in the US.
The best chance of curing the cancer is surgery to remove the cancerous tissue, but only 10 per cent of people have this option as it is normally only detected when the tumour has already started to spread to other parts of the body.
NHS advice states 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 at muscle strengthening exercises on at least two days a week.