Research reveals that vitamin D changes intestinal bacteria in mice and improves cancer immunity

Researchers from the Francis Crick Institute, the National Cancer Institute (NCI) of the National Institutes of Health (NIH), and Aalborg University in Denmark found that vitamin D stimulates the growth of a type of intestinal bacteria in mice. discovered to improve immunity. cancer.

reported in scienceResearchers found that mice fed a diet rich in vitamin D had improved immune resistance to experimentally transplanted cancers and improved response to immunotherapy treatment. This effect was also seen when gene editing removed a protein that binds to vitamin D in the blood and keeps it away from tissues.

Surprisingly, the research team found that vitamin D acts on epithelial cells in the intestine, resulting in an increase in the amount of a bacterium called Bacteroides fragilis. The microbe gave the mice better immunity against cancer because the transplanted tumors didn’t grow as much, but researchers still don’t understand how.

To test whether this bacterium alone could confer better cancer immunity, they fed Bacteroides fragilis to mice fed a normal diet. These mice were also better able to resist tumor growth, but not when fed a vitamin D-deficient diet.

Previous studies have suggested a link between vitamin D deficiency and cancer risk in humans, but the evidence is not conclusive.

To investigate this, researchers analyzed a data set from 1.5 million people in Denmark, highlighting the link between low vitamin D levels and increased cancer risk. Another analysis of cancer patient populations also suggested that people with higher vitamin D levels were more likely to respond well to immune-based cancer treatments.

Bacteroides fragilis is also present in the human microbiome, but further research is needed to understand whether vitamin D helps confer immune resistance to cancer through the same mechanism.

“What we showed here was surprising. “We can prioritize certain types of bacteria that give people better immunity.” For cancer.

“While this may one day be important for human cancer treatment, we do not know how and why vitamin D exerts this effect through the microbiome. More research is needed before we can conclusively say that improving cancer is effective.” Prevention or treatment? ”

Evangelos Giampazourias, a former post-doctoral research fellow at Crick University and currently group leader of the Cancer Immune Surveillance Group at the Manchester Institute of Cancer Research UK, said: “What differentiates a ‘good’ microbiome from a ‘bad’ microbiome? “It is a major challenge to accurately identify the We found that vitamin D helps gut bacteria induce cancer immunity and improves response to immunotherapy in mice.

“The key question we are currently trying to answer is how exactly vitamin D supports a ‘good’ microbiome. New ways to treat cancer have been uncovered, potentially offering exciting possibilities in the prevention and treatment of cancer.

“These findings raise the bar on the role of the microbiome in cancer immunity and how we can fine-tune this relationship to improve patient outcomes,” said Romina Goldschmid, Stadtmann Research Fellow in the NCI Cancer Research Center. contributes to the growing body of knowledge regarding potential dietary interventions; however, further research is required to fully understand the underlying mechanisms and how they can be exploited to develop individualized treatment strategies. Is required.”

Dr Nisharnthi Duggan, research information manager at Cancer Research UK, said: ‘We know that vitamin D deficiency can cause health problems, but there is not enough evidence linking vitamin D levels to cancer risk. This early-stage mouse study, combined with analysis of Danish population data, seeks to address gaps in the evidence, but the findings suggest a possible link between vitamin D and the immune response to cancer. further research is needed to confirm this.

‘Exposure to a little sunlight can help our bodies produce vitamin D, but we don’t need sunbathing to accelerate this process. Just spending a short amount of time in the sun can produce enough vitamin D. Also, getting vitamin D from your diet or supplements can reduce your risk of cancer by staying safely in the sun. So, when the sun is strong, always seek shade, cover up, and wear sunscreen.”