Breast cancer as an infectious disease

Two hypotheses of dense breasts and viral infection for explaining incidence of breast cancer by age group in Korean women

Breast cancer, the second leading type of cancer in Korean women, has shown increasing incidence over the past 10 years. However, the curves of incidence by age group cast doubt on the birth cohort effect hypothesis. To explain the curves, here I suggest two alternative hypotheses of breast density and viral infection based on pre-existing evidences. Evaluating these hypotheses would require important clues to find unknown risk factors of breast cancer and to plan more effective strategies for breast cancer control in Korean women.

Contribution of toll-like receptor signaling pathways to breast tumorigenesis and treatment

Mounting evidence indicates that anomalies in the inflammatory and immune response pathways are essential to tumorigenesis. However, tumor-based innate immunity initiated by transformed breast epithelia tissues has received much less attention. This review summarizes published reports on the role of the toll-like receptor signaling pathway on breast cancer risk, disease progression, survival, and disease recurrence. Specifically, we discuss the underlying biological mechanisms that contribute to the tumorigenic and/or anti-tumorigenic properties of toll-like receptors and their associated agonists in relation to breast tumorigenesis and cancer treatment. Further, we use results from preclinical, clinical, and population-based studies as prompts for the exploration of new and more effective breast cancer therapies. As the knowledge base of innate immunity's involvement in breast cancer progression increases, current and new immune-modifying strategies will be refined to effectively treat breast cancer.