JOONDALUP, Australia — Exercise may hold the key to fighting off cancerous tumors in the body, according to a breakthrough study. Researchers from Edith Cowan University say breaking a sweat doesn’t just improve health overall, it releases a secret weapon which slows down the disease.
The Australian team finds that exercise causes a patient’s muscles to secrete proteins called myokines into the blood. Myokines have the power to suppress tumor growth, helping the body fight off cancer cells.
Researchers examined a group of obese prostate cancer patients participating in a regular exercise program for 12 weeks. The team took blood samples from these patients before and after this exercise program. They then applied those blood samples directly to living prostate cancer cells.
“The patients’ levels of anti-cancer myokines increased in the three months,” says Professor Robert Newton in a university release.
“When we took their pre-exercise blood and their post-exercise blood and placed it over living prostate cancer cells, we saw a significant suppression of the growth of those cells from the post-training blood,” Prof. Newton adds. “That’s quite substantial indicating chronic exercise creates a cancer suppressive environment in the body.”
Myokines call in the body’s cancer fighters
Research leader Jin-Soo Kim notes that myokines may be the secret weapon in slowing down or stopping cancer growth, but they don’t do the actual killing. Instead, they actually signal the immune system to get in gear and go.
“Myokines in and of themselves don’t signal the cells to die,” Kim explains. “But they do signal our immune cells – T-cells – to attack and kill the cancer cells.”
Prof. Newton adds that exercise — which triggers these myokines — also complements other prostate cancer treatments like androgen deprivation therapy. For obese patients however, there are some dangers from this kind of therapy. One risk is the loss of lean mass and an increase in fat mass — which can result in poorer health and worse cancer outcomes.
During the study, all the participants engaged in a training program helping them to maintain lean mass while losing fat during their cancer treatments.
Exercise is a sword that can help slay all cancers
Study authors focused on prostate cancer because it is the most common non-skin cancer among men and has a high mortality in comparison to other forms of the disease. Despite only working with these patients, the researchers say releasing myokines into the blood should be effective against all forms of the disease.
“We believe this mechanism applies to all cancers,” Prof. Newton says.
The ECU team is now carrying out further studies, including one trial involving patients with advanced-stage prostate cancer on a six-month exercise program.
“These men have high disease burden, extensive treatment side-effects and are very unwell, but they still can produce anti-cancer medicine from within,” Newton concludes. “It’s important as it may indicate why men even with advanced cancer, if they’re physically active, don’t succumb as quickly.”
The findings appear in the journal Medicine and Science in Sports and Exercise.