Gum disease bacterium linked to breast cancer growth and spread

A common oral bacterium tied to gum disease may help spark and fuel breast cancer, according to new research. Scientists discovered it can travel through the bloodstream to breast tissue, where it causes DNA damage and speeds tumor growth and spread. It also appears to make cancer cells more aggressive and resistant to therapy. The effect is even stronger in people with BRCA1 mutations, raising new questions about the role of oral health in cancer risk.