<i>Porphyromonas gingivalis</i> May Contribute to Esophageal Cancer
In research that points to a possible link between oral microflora and esophageal cancer, a pathogen responsible for gingivitis has been found in 61% of study subjects with esophageal cancer. An international team led by researchers from the University of Louisville (UofL) School of Dentistry in Kentucky says the finding suggests that Porphyromonas gingivalis may be classified as a risk factor for esophageal cancer. The team notes this may lead to P. gingivalis being used as a prognostic biomarker for esophageal cancer.
Huizhi Wang, MD, PhD, an assistant professor of oral immunology and infectious diseases in the UofL School of Dentistry, characterizes the discovery as “the first direct evidence that P. gingivalis infection could be a novel risk factor for esophageal squamous cell carcinoma.” Wang notes that if the data are confirmed, it’s possible that eradicating this pathogen could lead to a significant reduction in the incidence of esophageal cancer. The study, “Presence of Porphyromonas gingivalis in Esophagus and its Association With the Clinicopathological Characteristics and Survival in Patients With Esophageal Cancer,” was published in Infectious Agents and Cancer.
In collaboration with the College of Clinical Medicine of Henan University of Science and Technology in Luoyang, China, the UofL team tested tissue samples from 100 patients with esophageal cancer, and compared them to 30 healthy controls. Measuring the expression of an enzyme unique to P. gingivalis, as well as the presence of the bacterial cell DNA within the esophageal tissues, researchers found both to be significantly higher in the cancerous tissue than in surrounding tissue or normal control sites. In addition, the presence of P. gingivalis was found to correlate with cancer cell differentiation, metastasis and overall survival rates.
The results led researchers to conclude that either esophageal cancer cells provide an ideal host for P. gingivalis, or the presence of this oral pathogen facilitates development of esophageal cancer. If the latter proves to be the case, Wang suggests that “improving oral hygiene may reduce risk, screening for P. gingivalis in dental plaque may identify susceptible subjects, and using antibiotics or other antibacterial strategies may prevent the progression of esophageal cancer.”