Researchers Find Link Between Oral Bacteria and Esophageal Cancer

Researchers Find Link Between Oral Bacteria and Esophageal Cancer

A team of researchers at the University of Louisville (UofL) School of Dentistry in Kentucky has discovered that a bacterial species responsible for gingivitis is also present in 61% of patients with esophageal cancer. Such a finding, the team reports, suggests that the bacteria Porphyromonas gingivalis may be classified as a risk factor for esophageal cancer—and perhaps lead to the bacteria being identified as a biomarker for esophageal cancer. 

Findings of the study “Presence of Porphyromonas Gingivalis in Esophagus and its Association With the Clinicopathological Characteristics and Survival in Patients With Esophageal Cancer” were published in Infectious Agents and Cancer early this year. In a UofL press release, researcher and study contributor Huizhi Wang, MD, PhD—an assistant professor of oral immunology and infectious diseases in the UofL School of Dentistry—revealed that this discovery provides “the first direct evidence that P. gingivalis infection could be a novel risk factor for [esophageal cancer]… These data, if confirmed, indicate that eradication of a common oral pathogen may contribute to a reduction in the significant number of people suffering with [esophageal cancer].”

To reach this conclusion, researchers at UofL—in collaboration with the College of Clinical Medicine of Henan University of Science and Technology in Luoyang, China—tested tissue samples from 100 patients with esophageal cancer and compared them to 30 healthy controls. Measuring the expression of an enzyme unique to the bacteria in question, 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 of individuals with esophageal cancer than in surrounding tissue. Additionally, the presence of P. gingivalis was also found to correlate with cancer cell differentiation, metastasis, and overall survival rates.

The data led the researchers to conclude that either esophageal cancer cells provide an ideal host for P. gingivalis or that bacterial infection facilitates development of esophageal cancer. If the latter is correct, a solution is already at hand. “Should P. gingivalis prove to cause esophageal cancer, the implications are enormous,” Wang said. “It would suggest that improving oral hygiene may reduce risk; screening for P. gingivalis in dental plaque may identify susceptible subjects; and using antibiotics or other anti-bacterial strategies may prevent esophageal cancer progression.”

Hygiene Connection E-Newsletter

March 2016