The role of the immune system in early epithelial carcinogenesis: B-ware the double-edged sword.

Cancer is commonly described as a disease of genetic mutations. However, epidemiologic and clinical evidence points to the important but multifaceted role of the host. The immune system has something to say about cancer evolution through promotion of malignancy by inflammatory myeloid cells of the innate immune system. In a report in this issue of Cancer Cell, B cells are implicated as key players in the regulation of chronic inflammation that promotes early events in epithelial carcinogenesis. These are surprising observations, linking antibodies of the adaptive immune system to innate immune responses that drive epithelial carcinogenesis.