A recent study points to gut health as a significant factor in the spread of breast cancer to other body parts. An unhealthy gut can lead to a buildup of bile acids, which may promote the metastasis of breast cancer, indicating potential new prevention strategies.
Research led by Dr. Melanie Rutkowski at the University of Virginia Comprehensive Cancer Center highlights the influence of microorganisms in the intestines on the spread of hormone receptor-positive (HR+) breast cancer. Dr. Rutkowski explained to Newsweek that an imbalanced gut microbiome loses control of bile acid levels. These acids are crucial signaling molecules, and their dysregulation can disrupt metabolism and immune function, creating conditions conducive to the spread of breast tumors.
HR+ breast cancer represents the most common form of metastatic breast cancer. The Breast Cancer Research Foundation reports that about 80% of breast cancers are HR+, with approximately 225,000 new diagnoses each year in American women. Once HR+ breast cancer metastasizes, treatment becomes more challenging, increasing mortality risk.
Dr. Rutkowski shared more insights via EurekAlert!, noting the potential of modifying bile acid composition or using bile acid sequestrants, which are already FDA-approved for other conditions, to reduce metastasis. The research builds on previous findings linking gut microbiome imbalance to poor outcomes and specifically identifies bile acid buildup as a trigger for inflammation that aids cancer cell spread.
Co-author Dr. Audrey Putelo indicated that since bile acids can be quantified and altered, these discoveries pave the way for developing strategies to identify high-risk patients and decrease metastatic disease chances. The study found a correlation between elevated bile acids, insulin resistance, and lower survival rates in HR+ breast cancer patients. Nonetheless, patients with metastatic conditions who received bile acid-suppressing drugs often had improved survival rates, warranting further investigation into these drugs’ direct effects.
Dr. Rutkowski expressed optimism about the results, emphasizing ongoing research to explore whether existing FDA-approved medications might prevent initial cancer spread. The research team is analyzing patient data to determine the efficacy of long-term use of these drugs. Additionally, due to a lack of established methods to stably modify the microbiome, efforts continue to understand immune-related effects of bile acid signaling in tissues typically affected by breast tumor spread. This work aims to identify new targets to curb tumor dissemination.