We’ve long known that the gut microbiome plays a huge role in digestion — but current research keeps revealing just how deeply these microbes are tied to our overall health. From supporting brain function to fine-tuning our immune response and even lowering the risk of chronic diseases, the list of their benefits keeps growing.
Now, a new study published in Cell by researchers at Weill Cornell Medicine in New York suggests that the microbiome may go even further — by turning bile acids into immune-boosting compounds that help the body fight cancer.
According to a press release, co-author and researcher Chun-Jun Guo was very surprised by their findings. Until now, no one had discovered that these microbiome-modified bile acids could interfere with the signaling processes that allow cancer cells to grow unchecked.
How Bile Acids Shape the Microbiome
Produced in the liver, stored in the gallbladder, and released into the small intestine after eating, bile acids are mostly known for breaking down dietary fats and helping absorb fat-soluble vitamins like A, D, E, and K. But they also play a part in shaping the gut microbiome — thanks to their ability to break down harmful bacteria and influence the makeup of microbial communities.
Interestingly, this relationship goes both ways. Once bile acids reach the gut, our microbes modify them into new metabolites, which can have a range of effects on our health. While scientists knew about this transformation, the exact molecular mechanisms and effects have remained something of a mystery — until now.
Read More: New Clues to Chronic Disease Turn Up in the Gut
Metabolites Activate Cancer-Fighting T Cells
The Cornell team began by identifying the specific molecules that result when gut microbes alter bile acids. They found over 50 new types of secondary bile acids — many of which structurally resemble hormones like testosterone and estrogen. That similarity made them wonder: could these new molecules also interact with hormone receptors?
It turns out, yes — they can. One of the newly discovered metabolites was able to block the androgen receptor, protein structures found in various cell types, including cancer and immune cells. Blocking this receptor has already been shown in past studies to enhance the effectiveness of T cells, the immune system’s frontline fighters against infections and tumors.
So, the team decided to test whether these bile acid metabolites could actually slow tumor growth. When they treated mice with bladder cancer using one of the secondary bile acids, they saw promising results: the modified bile acid appeared to boost T cell activity, which in turn suppressed the growth of tumors.
Toward Better Cancer Therapies
These findings suggest a new way to potentially improve cancer treatments — by either reshaping a patient’s microbiome with beneficial bacteria or directly delivering bile acid metabolites that enhance immune response.
“This study highlights the profound and evolving partnership between the human host and its gut microbiota, emphasizing the importance of integrating microbial activity into the design of future cancer therapies,” said co-author David Artis in the news release. “It also exemplifies the power of multidisciplinary collaboration in driving microbiome science toward deeper molecular understanding of host–microbe interactions.”
Before this kind of treatment can become a reality, though, more work is needed. The researchers hope to better understand how these microbiome-derived bile acids affect the body as a whole — and to explore the full range of ways our gut bacteria might influence our biology at the molecular level.
Read More: It Doesn't Take Long to Reset Your Gut Health with Small Lifestyle Changes
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
Cell: Microbiota-derived bile acids antagonize the host androgen receptor and drive anti-tumor immunity
Gut Microbes: Bile acids as modulators of gut microbiota composition and function
Nature Reviews Microbiology: Bile acids and the gut microbiota: metabolic interactions and impacts on disease
Having worked as a biomedical research assistant in labs across three countries, Jenny excels at translating complex scientific concepts – ranging from medical breakthroughs and pharmacological discoveries to the latest in nutrition – into engaging, accessible content. Her interests extend to topics such as human evolution, psychology, and quirky animal stories. When she’s not immersed in a popular science book, you’ll find her catching waves or cruising around Vancouver Island on her longboard.
