Chronic Inflammation

Chronic inflammation has a distinctive role in cancer development and is clearly seen in both HBV viruses and H. pylori induced cancers. There are several different cellular evets that occur during an inflammatory response. Oncogenes, such RAS and myc, regulate the expression of tumor-promoting inflammatory cytokines. Important cells involved in inflammatory responses are macrophages. Macrophages produces tumor  necrosis factor- alpha (TNF-a), which helps regulate the inflammatory response. Chronic inflammation is associated with increased production of ROS and NOS causing increased risk of DNA damage and mutations. Once these mutations accumulate and a tumor has developed, the immune response continues, resulting in tumor progression.