Recent research has uncovered an unexpected connection between oral health and breast cancer. Scientists found that a common bacterium linked to gum disease can enter the bloodstream and settle in breast tissue, leading to DNA damage and promoting the growth and spread of tumours.
The study, conducted by the Johns Hopkins Kimmel Cancer Center and the Bloomberg-Kimmel Institute for Cancer Immunotherapy, indicates that this bacterium not only affects the tissue but also makes cancer cells more aggressive and less responsive to treatment. Dr Dipali Sharma noted that the research was motivated by previous smaller studies that showed a link between periodontal disease and breast cancer.
Dr Sheetal Parida, the first author of the study, stated the team aimed to explore these connections further. They used mouse models and human breast cancer cells to investigate how the bacterium impacted breast tissue. The research revealed that when the bacterium was introduced into breast ducts, it caused inflammation and DNA damage, whereas when it entered the bloodstream, it significantly accelerated the growth of existing tumours.
The study also identified a crucial biological process: exposure to the bacterium damaged cellular DNA, activating repair mechanisms that could introduce errors. Additionally, it raised levels of a protein called PKcs, associated with cancer cell movement and resistance to chemotherapy.
While the findings highlight a potential link between oral microbes and the risk of breast cancer, further research is needed to understand its implications for patient care. Dr Sharma emphasized that these results suggest that various risk factors, including genetic ones like BRCA1 mutations, may interact with this bacterium, increasing breast cancer risk and tumour aggressiveness.
