Recent research suggests that vitamin D could potentially enhance cancer immunity by promoting the growth of certain gut bacteria in mice. Scientists from the Francis Crick Institute, the National Cancer Institute, and Aalborg University made this discovery, hinting at the future possibility of using vitamin D to combat cancer.
Vitamin D enhances immunity for transplanted cancers
Researchers discovered that mice fed a vitamin D-rich diet exhibited enhanced immune resistance to transplanted cancers and improved responses to immunotherapy. This effect persisted even after removing a protein that binds to vitamin D in the blood, preventing its access to tissues.
The research team discovered that vitamin D affects intestinal epithelial cells, leading to an increase in Bacteroides fragilis bacteria, which boosts immunity to cancer in mice. Transplanted tumors in mice didn’t grow as much with increased B. fragilis, but the reasons remain unclear. Testing showed that B. fragilis alone improved cancer immunity in mice on a normal diet but not in those on a vitamin D-deficient diet.
Past research explored the potential correlation between vitamin D levels and cancer risk, analyzing data from 1.5 million Danish individuals. Findings indicated a connection between lower levels of vitamin D and increased cancer risk. Additionally, a separate analysis on cancer patients suggested that higher vitamin D levels might enhance responses to immune-based cancer therapies.
Vitamin D influences gut microbiome
Further investigation is required to ascertain whether vitamin D contributes to immune resistance against cancer via similar mechanisms, despite the presence of Bacteroides fragilis in the human microbiome.
Researchers at the Crick Institute have discovered that vitamin D has the ability to influence the gut microbiome in a way that enhances immunity to cancer in mice. This finding, led by Caetano Reis e Sousa, suggests potential implications for cancer treatment in humans, although further research is required to fully understand how vitamin D achieves this effect through the microbiome.
Evangelos Giampazolias, formerly at the Crick Institute and now leading the Cancer Immunosurveillance Group at the Cancer Research UK Manchester Institute said that vitamin D assists gut bacteria in enhancing cancer immunity, thereby improving the effectiveness of immunotherapy in mice.