Humoral immunity, inflammation and cancer.

Clinical and experimental data now clearly indicate that chronic inflammation significantly contributes to cancer development. Emerging out of these studies is an appreciation that persistent humoral immune responses exacerbate recruitment and activation of innate immune cells in neoplastic microenvironments where they regulate tissue remodeling, pro-angiogenic and pro-survival pathways that together potentiate cancer development. Population-based studies examining individuals with chronic inflammatory disorders have revealed that states of suppressed cellular immunity, in combination with enhanced humoral immunity and humoral immunity-associated cytokines, cooperate and effectively suppress anti-tumor immune responses while simultaneously enhancing angiogenesis and presumably overall cancer risk in afflicted tissue. In addition, studies in transgenic mouse models of de novo organ-specific cancer development have revealed that inflammation mediated by immunoglobulins and immune complexes might be functionally significant parameters of tumor promotion and progression. These recent advances support the hypothesis that enhanced states of local humoral and innate immune activation, in combination with suppressed cellular immunity and failed cytotoxic T cell anti-tumor immunity, alter cancer risk and therefore represent powerful targets for anti-cancer immunotherapeutics.