Creatine is best known as a popular supplement used by athletes and bodybuilders to improve strength and performance.
Now, new research from the University of California, Los Angeles (UCLA) suggests it may also help the immune system fight cancer.
The study, published in iScience, found that creatine can boost the activity of important immune cells that help the body recognize and attack tumors.
The findings add to earlier research showing that creatine can power cancer-fighting T cells, a type of white blood cell that directly attacks cancer cells.
In the new study, researchers focused on another group of immune cells called dendritic cells. These cells act like scouts for the immune system.
They detect threats, collect pieces of tumors, and then “teach” T cells what to attack.
According to the researchers, many cancer immunotherapies work by stimulating T cells. However, only about 20% to 40% of patients respond well to these treatments.
Improving the function of dendritic cells may help more patients benefit from immunotherapy.
The team discovered that dendritic cells inside tumors had much higher levels of a protein that transports creatine into cells.
This suggested that creatine may play an important role in keeping these immune cells active.
To investigate further, the scientists created dendritic cells that could no longer absorb creatine. These cells did not survive as well, became less active, and were less effective at preparing T cells to fight cancer. T cells exposed to these creatine-deficient dendritic cells also became weaker and produced fewer molecules needed for an anti-cancer response.
The researchers then tried increasing creatine levels instead. In mice with melanoma, daily creatine injections slowed tumor growth. The treated mice had more active dendritic cells inside their tumors, and these cells produced stronger signals that attracted additional immune cells to the cancer site.
The researchers found that creatine increased levels of ATP, the molecule that serves as the cell’s main source of energy. Tumors consume enormous amounts of nutrients, creating a difficult environment for immune cells. Creatine appeared to help dendritic cells maintain a steady supply of energy, allowing them to continue functioning even under these challenging conditions.
The team also tested human immune cells in the laboratory. Creatine improved the activity of human dendritic cells and enhanced their ability to stimulate T cells against cancer-related targets. The findings suggest that creatine might eventually improve dendritic cell-based cancer vaccines as well.
The researchers stress that the study was conducted only in mice and laboratory-grown human cells. It does not prove that creatine supplements can help cancer patients. Although creatine has been widely used for decades and is generally considered safe when taken at recommended doses, anyone undergoing cancer treatment should speak with their doctor before taking any supplements.
The next step will be clinical trials to determine whether creatine supplementation can safely improve the effectiveness of cancer immunotherapy in patients.
