Researchers in this study wanted to understand whether the bacteria (microbiome) present in breast tissue might play a role in breast cancer. While scientists have studied bacteria in places like the gut, much less is known about the microbial environment inside the breast, especially in healthy tissue. The goal of this study was to define what a “normal” breast microbiome looks like and how it differs from cancerous tissue.
To do this, the researchers analyzed breast tissue samples from over 400 healthy women and compared them to samples from breast cancer patients, including tumor tissue and nearby “normal” tissue. They used advanced genetic sequencing to identify different types of bacteria and examined how these bacteria relate to gene activity within the tissue.
The researchers found that healthy breast tissue contains specific types of bacteria, including Lactobacillus, Acetobacter, and Xanthomonas, which were much less common in tumor tissue. In contrast, a bacterium called Ralstonia was more abundant in breast tumors and nearby tissue. They also found that the types and amounts of bacteria were influenced by factors such as age, race, and reproductive history.
Overall, the study suggests that changes in the breast microbiome—known as dysbiosis—may be linked to cancer development or progression.
