Research progress on the study of the relationship between periodontitis and cancers of the digestive system

Periodontitis is closely related to many systemic diseases. Cancer of the digestive system is a common malignant tumor. Increasing evidence has shown that periodontitis is related to various digestive system cancers. This review summarizes the current research on the relationship between periodontitis and esophageal cancer, gastric cancer, and colorectal cancer and analyzes the possible mechanisms, including via microorganisms, immunity, inflammation, and genes. The content of periodontal pathogens and Helicobacter pylori in the mouth of patients with periodontitis is increased, with the secretion of many virulence factors and pathogenic enzymes and inhibition or evasion of the host's nonspecific immune function, making the digestive system organs connected to the oral cavity more vulnerable to cancer cell invasion. The plasma levels of interleukin-1β(IL-1β), interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) in patients with periodontitis and digestive system cancers are increased. These elevated factors promote the occurrence and development of cancer by activating endothelial cells, increasing the expression of adhesion molecules and inducing the production of matrix metalloproteinases. Additionally, formyl peptide receptors involved in the inflammatory response and NF-κB, as therapeutic targets of periodontitis, are associated with many cancers, but the mechanism is unclear. Periodontal health is considered a breakthrough point to provide a reference for the prevention and treatment of patients with these three common cancers of the digestive system.