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UI study finds possible link between gut bacteria and breast cancer

Date: Thursday, February 9, 2023

A new study conducted by UI researchers with the lab of Ashutosh Mangalam, PhD, associate professor of pathology, explores a potential link between gut bacteria and breast cancer in individuals from the Midwest. 

“While some genetic and environmental risk factors for breast cancer are known, they don’t make up the whole story,” says Mangalam, who is also a member of Holden Comprehensive Cancer Center. “Like we have previously found with multiple sclerosis, this study supports that promoting the development of healthy gut microbiota could provide health benefits for patients with breast cancer.” 

Further investigation of the link between breast cancer and the microbiome could lead to new methods for early screening and diagnosis of breast cancer, as well as the development of new treatments that target alterations in gut bacteria. 

Good bacteria, bad bacteria

The gut’s ecosystem of natural bacteria, or “microbiome,” plays an important role in our health. Good bacteria break down food, produce vitamins and other nutrients, and can even enhance our immune system; bad bacteria can disrupt the microbiome, possibly contributing to the development of disease. Data gained from studying the relationship between the microbiome and states of health and disease is limited, however, by the fact that people's microbiomes can differ significantly based on where they live. 

“Interestingly, we found that patients with breast cancer had different levels and types of bacteria compared to the healthy people we studied, suggesting that the gut microbiome might be linked to breast cancer,” says Jessie Knobbe, a third-year student in the UI Carver College of Medicine’s Medical Scientist Training Program who worked on the study. 

Published Jan. 11 in Scientific Reports, the study found that when compared to healthy individuals, the participants who had breast cancer had less of a kind of gut bacteria that breaks down plant-derived carbohydrates. The bacteria turn the carbs into beneficial molecules called short-chain fatty acids, which play a crucial role in maintaining gut health. 

“These findings are truly exciting because gut bacteria profiling could give doctors more information about each breast cancer patient, opening the door for personalized medicine,” says Rachel Shrode, a PhD candidate in the Interdisciplinary Graduate Program in Informatics who contributed to the study. 

The study was conducted with an interdisciplinary team of basic scientists, clinical cancer providers, and epidemiologists across the University of Iowa, including Nicole Cady; Meeta Yadav, MBBS, DCH; Jemmie Hoang; Catherine Cherwin, PhD, RN; Melissa Curry; Rohan Garje, MBBS; Praveen Vikas, MBBS; Sonia Sugg, MD; Sneha Phadke, DO; and Edward Filardo, PhD.