Breast cancer, the single most prevalent cancer in women worldwide, is always subject to both media attention and research — but how well do we really understand this cancer?
We know that breast cancer is likely caused by a combination of genetic and environmental factors. You've probably heard that drinking alcohol, smoking, being obese and leading a sedentary lifestyle increases your risk of developing breast cancer, while the hormonal component means that breastfeeding reduces your odds, and if you're interested in health news, you'll regularly hear about new breast-cancer related studies.
A Canadian research team, previously having proven that there is such a thing as a breast microbiome (meaning that bacteria populate your breasts!), set out to discover what the true relationship between those breast-tissue bacteria and breast cancer is. Their study is more than yet another news item you'll read and then forget about. Rather, their study could revolutionize our understanding of breast cancer.
Breasts, Bacteria, And Breast Cancer
The research team, led by Gregor Reid of the University of Western Ontario, collected and analyzed tissue samples from 70 women to study their breast microbiota. Samples were taken from women suffering from breast cancer, women who had benign breast tumors, and women who had completely healthy breasts. The tissues the research team took were placed in sterile vials, on ice, right away and homogenized within half an hour of collection. As a control, the researchers additionally set up other vials that were left open for the duration of the patients' surgical procedures, and skin swabs were taken from the participants' disinfected breasts. All three samples were then studied.
These bacterial groups are, incidentally, those that have the capacity to damage DNA. These women's breast microbiota also showed a decrease in the lactic acid bacteria known for their contribution to health in general, and cancer-protective properties in particular.
What Is The Relationship Between Harmful Bacteria And Breast Cancer?
The study's finding that the breast microbiota of women without breast cancer differ from those with it is ground-breaking in itself, but what is really going on here? Does the presence of DNA-damaging bacterial colonies lead to breast cancer, or does breast cancer merely give these bacteria a chance to thrive? This remains unknown, for now.
Particularly interesting was the researchers' conclusion that the microbiota of women with benign tumors more closely resembled those of women with breast cancer than those with healthy breasts. This, the researchers wrote, "raises the question as to why these women with benign tumours do not have cancer, if we believe there could be a link between bacteria and breast cancer". They added: "In women with benign disease, DNA damage caused by bacteria could be responsible for enhanced cellular proliferation leading to tumour formation, similar to what may be occurring in cancer patients, however, other factors that could promote transformation and malignancy of this tumor is reduced in these women compared to those with cancer."