Gut bacteria metabolite may help breast cancer to grow

25.09.2026

Targeting deoxycholic acid (DCA)-producing gut bacteria could be a way to slow breast cancer progression.

What is already known

Breast cancer is influenced not only by tumor cells, but also by the body environment, including metabolism, immunity, and the gut microbiota. Previous work has linked gut microbes to cancer, but the exact microbial species, molecules, and immune pathways involved in breast cancer have been unclear.

What this research adds

Researchers studied samples from human breast disease and mouse breast cancer models and found that one group of bacteria called Lachnospiraceae, including Eubacterium bolteae, increased with breast cancer progression. This effect was linked to higher levels of deoxycholic acid, or DCA—a microbiota-derived bile acid that accumulates in tumors. In tumor cells, DCA triggered the production of molecules that recruited immune-suppressive cells and helped tumors to grow.

Conclusions

The findings suggest that targeting DCA-producing gut bacteria could be a way to slow breast cancer progression.

Breast cancer is influenced not only by tumor cells, but also by the body environment, including metabolism, immunity, and the gut microbiota. Now, researchers have found that gut bacteria may help breast cancer to progress by producing a metabolite called deoxycholic acid, or DCA.

The findings, published in Cell Metabolism, suggest that targeting DCA-producing gut bacteria could be a way to slow breast cancer progression.

Previous work has linked gut microbes to cancer, but the exact microbial species, molecules, and immune pathways involved in breast cancer have been unclear.

To test which gut microbes influence tumor growth, Lili Li at Zhejiang University School of Medicine in Hangzhou, China, and her colleagues studied samples from human breast disease and mouse breast cancer models.

Increased Lachnospiraceae

The researchers looked at gut bacteria in people with non-cancerous breast conditions, early breast cancer, and invasive breast cancer. They found that the mix of gut bacteria changed as disease became more advanced. One group of bacteria, called Lachnospiraceae, was common in people with invasive or more advanced breast cancer. The researchers saw the same pattern in mice.

Mice receiving microbes from tumor-bearing donors developed larger tumors than mice receiving microbes from tumor-free donors. Their tumors also contained more immune-suppressive cells.

When mice were colonized with Eubacterium bolteae, a microbe belonging to the Lachnospiraceae family, tumors grew faster, the researchers found.

Tumor progression

Further analyses showed that the levels of the microbiota-derived bile acid DCA were higher in blood from people with malignant breast cancer than in those with benign breast disease. In mice, DCA accumulated inside tumor tissue and increased as tumors progressed.

Human breast tumors also had more DCA than nearby non-tumor tissue, and experiments done in cancer cells grown in a lab dish showed that DCA triggers the production of molecules that recruit immune-suppressive cells and help tumors to grow.

“These findings identify a microbiota-metabolite-immune axis driving breast cancer progression and uncover microbial metabolites as potential therapeutic targets,” the authors say.