Microflora and Breast Cancer: Are Some Bacteria Protective and Others Not?
Posted: Thursday, February 20, 2020
Inflammation in the breast ducts caused by pathogenic bacteria may increase the risk of breast cancer by disturbing the “stem cell hierarchy,” whereas lactose-fermenting bacteria may be protective, according to study findings published in Medical Hypotheses. R.J. Rigby, PhD, of Lancaster University in the United Kingdom, and colleagues also noted that consumption of yogurt appears to be protective.
“The stem cells that divide to replenish the lining of the breast ducts are influenced by the microflora, and certain components of the microflora have been shown in other organs, such as the colon and stomach, to increase the risk of cancer development,” the researchers stated in a Lancaster University press release. “Therefore, a similar scenario is likely to be occurring in the breast, whereby resident microflora impact on stem cell division and influence cancer risk.”
The investigators’ hypothesis suggests that pathogenic bacteria may result in an increased likelihood of breast cancer, perhaps because such bacteria result in periodontitis. That condition is associated with cancer of the breast, prostate, pancreas, and other areas. Those bacteria are also known to induce inflammation at additional epithelial sites. The researchers also noted that pathogenic microflora may affect the stem cells responsible for replenishing the lining of the breast ducts.
Furthermore, the investigators indicated that lactose-fermenting bacteria (microflora) found in the breast may be protective against the development of cancer. They believe that this statement is supported by the 4.3% reduction in the risk of breast cancer development for every year a woman breastfeeds reported in other studies. The researchers suggested that daily intake of natural yogurt may be an effective preventive measure, since yogurt and milk contain microflora that are similar to those found in the breasts of women who have breastfed.
Disclosure: The study authors reported no conflicts of interest.