Leukocytes play an important role in inflammation and cancer. They are attracted to the place of injury by chemotactic factors, e.g., plasma complement factors C5a and C3a, and chemotactic cytokines or chemokines, which are produced locally at the site of infection. Chemokines are produced by a variety of cell types including tumor cells. Leukocytes, selectively attracted by chemokines, will modulate the inflammatory response (phagocytosis) and affect tissue remodeling and tumorigenesis by the chemokine-induced release of proteases and other metabolites (1).