The type, location, and levels of inflammation-modulating factors, such as activator protein 1 (AP-1), catenin/Wnt (wingless related integration site), NF-B, PPAR-gamma, HIF-1 alpha (hypoxia-inducible factor-1 alpha), p53, inflammatory cytokines, chemokines, and growth factors, are all influenced by ROS; as a consequence, ROS play an essential part in establishing the relationship between chronic inflammation and cancer. The gene discussed is FOS; the disease is cancer.