New research discovers that a disruption in the gut microbiome results in more aggressive breast cancer. The findings of the study are published in the journal Cancer Research. The study states that fluctuations in the bacterial populations of the gut can potentially trigger severe tumor formation.
The outlook of people towards breast cancer has significantly improved in recent years. However, predicting and preventing the spread of cancer to other parts of the body is still a major challenge in the medical community.
Nearly, 154,794 women in the United States are living with metastatic breast cancer. According to the estimates, around 5–9% of new breast cancer cases are already in metastasis at the time of diagnosis.
There are numerous factors, influencing the likelihood of breast cancer and hormone receptor status is one of them. Hormone receptor-positive breast cancer accounts for the majority of breast cancer cases. It is driven by the hormones estrogen or progesterone and usually responds well to treatment. On the other hand, hormone receptor-negative cancers tend to spread faster.
Furthermore, a high level of macrophages also influences the spread of breast cancer. Some studies also report that increased amounts of collagen in the tissue and tumor also lead to increased breast cancer metastasis.
This respective research presents another factor that crucially affects cancer metastasis i.e. gut microbiome.
Disrupting gut bacteria induces inflammation
The study involved mice for the experiment analysis. The research team disrupted the natural gut bacteria of mice with breast cancer using powerful antibiotics. They used a mouse model of hormone receptor-positive mammary cancer and altered natural gut bacteria balance. They did so by giving them powerful antibiotics. In addition, they performed a fecal microbiota transplant of dysbiotic, or macrobiotically unbalanced, fecal contents. According to the researchers, this resulted in inflammation systemically and within the mammary tissue.
In such an inflamed environment, the tumor cells were observed to disseminate from the tissue into the blood and to the lungs. This is a major site for hormone receptor-positive breast cancer to metastasize.
The results of the research suggest that an unhealthy microbiome and its related tissue modifications can be early predictors of invasive or metastatic breast cancer. Moreover, the research team speculates that an unhealthy microbiome contributes to increased invasion and a higher incidence of metastatic disease.
These results don’t mean that antibiotics are dangerous for people with breast cancer by any means. The researchers warn the public not to generalize these results from mice to humans. In order to recreate the gut bacteria imbalance, humans would have to take far more antibiotics than the amount doctors usually prescribe.
The research experts advise maintaining a healthy microbiome or gut bacteria balance. This can be done by adopting a healthful diet that is high in fiber. Also, people must do exercise, sleep well and schedule practices that contribute to positive overall health. If one does all of these things, they are expected to observe a favorable outcome in the long term for breast cancer.