Vitamin D may balance gut microbiome to give cancer immunotherapy a boostShare on Pinterest

Over the past few years, researchers have focused on using vitamin D to prevent and treat different cancers.

• Previous research has looked at using vitamin D in conjunction with cancer immunotherapy.

• Researchers from The University of Manchester have found that vitamin D helps balance the gut microbiome, improving the way cancer immunotherapy treatments work via a mouse model.

Over the past few years, several studies have focused on using vitamin D to prevent and treat different types of cancers, including prostate, skin, breast, and bowel cancers.

Previous research has also linked high vitamin D levels to a decreased risk of developing cancer and a reduced cancer mortality rate.

Scientists have also examinedTrusted Source the use of vitamin D in conjunction with a newer type of cancer treatment called immunotherapy.

Now researchers from the Cancer Research UK Manchester Institute at The University of Manchester in the U.K. have found that vitamin D helps balance the gut microbiome, improving the way cancer immunotherapy treatments work, via a mouse model.

The study was recently published in the journal Science.

Using immunotherapy to fight cancer 

Immunotherapy is a type of treatment that uses the body’s immune system to help improve its ability to fight cancer.

Different types of immunotherapy treatments include monoclonal antibodiesTrusted Source, immune checkpoint inhibitorsTrusted Source, immune system modulatorsTrusted Source, cancer vaccinesTrusted Source, and adoptive cell therapiesTrusted Source like CAR T-cell therapy.

Over the years, the U.S. FDA has approvedTrusted Source several immunotherapy treatments for different types of cancers, with more being added over time.

“Immunotherapy reinvigorates the body’s immune system to attack cancer cells,” Evangelos Giampazolias, PhD, group leader of the Cancer Immunosurveillance Group at the Cancer Research UK Manchester Institute, the University of Manchester and lead author of this study, explained to Medical News Today.

“Immunotherapy has revolutionized the treatment of one of the deadliest forms of cancer, metastatic melanomaTrusted Source, and now is approved as a forefront treatment in a wide range of malignancies including those of kidneyTrusted Source and lungTrusted Source,” Giampazolias said.

“However, not all patients respond equally well to this therapy, and only a small group experience long-lasting (benefits),” Giampazolias continued. “Therefore, understanding when and how our immune system identifies malignant cells as a threat is critical for designing therapies that boost its ability to eliminate cancer,” he added.

How does vitamin D affect gut health and cancer treatment?

Giampazolias said that he and his colleagues were intrigued by the fact that the cancer-protective role of vitamin D was absent in mice treated with antibiotics or raised in sterile environments without any living microorganisms.

“Based on these (findings) we hypothesized that vitamin D promotes cancer immunity by influencing the communities of ‘friendly’ microorganisms that live inside the animals, known as (the) microbiome.

We found that vitamin D affects the cells lining the intestine, causing an increase in the levels of a bacteria called Bacteroides fragilisTrusted Source.”

– Evangelos Giampazolias, PhD

According to Giampazolias, Bacteroides fragilis is a member of a larger community of microorganisms inhabiting the intestines of mice and humans.

“To determine if the bacteria alone could improve immunity to cancer, mice on a diet containing standard levels of vitamin D were given Bacteroides fragilis,” Giampazolias said. “These mice showed improved ability to resist tumor growth. However, this effect was not observed when the mice were given (a) diet deficient in vitamin D.”

“It is still unclear how Bacteroides fragilis (promotes) anti-cancer immunity but overall, our findings highlight an unprecedented link between vitamin D and gut microbiome that influences immune responses to cancer in mice,” he continued. “Further work is warranted to confirm a possible link between vitamin D and cancer immunity in humans.”

Potential new avenues for improving cancer treatment

After reviewing this study, Anton Bilchik, MD, PhD, surgical oncologist, chief of medicine, and director of the Gastrointestinal and Hepatobiliary Program at Providence Saint John’s Cancer Institute in Santa Monica, CA, told MNT this is a very important study because while doctors have known that vitamin D is important in preventing cancers, the mechanism has been unclear.

Bilchik noted:

“This is one of the first studies to suggest that vitamin D influences a bacteria within our body Bacteroides, which then influences the immune system to reduce the chance of getting cancer. But even more important, demonstrates that immunotherapy is likely to be more effective in the presence of vitamin D. So these are completely novel mechanisms that have been described.”

MNT also spoke with Shama Farooq, MD, MBBS, a neuro-oncologist at Hackensack Meridian Neuroscience Institute at Jersey Shore University Medical Center and assistant professor in the Department of Neurology at Hackensack Meridian School of Medicine in New Jersey.

Farooq said these findings suggest a potential link between vitamin D levels, the microbiome, and cancer immunity, offering potential new avenues for improving cancer treatment and prevention strategies:

“Continued research into enhancing the body’s immunity and optimizing immunotherapy is crucial because cancer is a complex disease with diverse mechanisms of evasion. By exploring new ways to boost the immune system’s ability to recognize and destroy cancer cells, researchers can develop more effective and targeted treatments, ultimately improving patient outcomes and survival rates.”

How much vitamin D is needed to help lower cancer risk? 

Based on this research, readers may wonder if they should make sure their vitamin D levels are correct to help potentially lower their cancer risk.

Bilchik said it’s important for vitamin D levels to be within the normal range, not only for perhaps the prevention of cancer but also because it plays a very important role in bone density, reduction in fracturesTrusted Source, and reducing the chance of osteoporosis.

“Vitamin D plays many important roles and despite the fact that vitamin D is easily available through plants, meat, (and the) sun, it’s surprising how many people are vitamin D deficient,” he added.

According to the U.S. National Institutes of Health, levels of 50 nanomoles per liter of vitamin D or aboveTrusted Source are the healthy range for bone and overall health for most people. Levels below 30 nanomoles per liter or above 125 nanomoles per liter may cause health issues.

“Based on this study, readers should consider ensuring their vitamin D levels are adequate as part of a comprehensive approach to potentially lowering their risk of cancer,” Farooq said. “While more research is needed to fully understand the relationship, maintaining optimal levels of vitamin D is generally beneficial for overall health and may contribute to reducing cancer risk.”