Inflammation and skin cancer: old pals telling new stories.

Inflammation and the inflammatory infiltrate essentially contribute to tumor development and progression. For skin cancer, the observation that tumors arise in sites of chronic irritation and inflammation dates back to 1828 and has stimulated a whole field of research. Numerous animal models such as models of UV-induced or chemically induced skin carcinogenesis but also trangenic models support the role of a deregulated inflammation in the development of skin cancer. These models have greatly contributed to our understanding of the multistage process of carcinogenesis and have given important insights in the differences between physiological inflammation in a healing wound and the functional contribution of the deregulated tumor-associated inflammation to skin cancer growth and progression. Data from these models are supported by epidemiological studies that emphasize a connection of inflammatory conditions with the development of melanoma and epithelial skin cancer and give first indications for a beneficial effect of anti-inflammatory treatments in reducing the risk for skin cancer. Consequently, anti-inflammatory drugs might represent a highly interesting approach in the prevention and treatment of skin cancers.