DNA ‘Marks’ Gastric Cancer Risk

Infection with the stomach-dwelling bacterium Helicobacter pylori is a strong risk factor for gastric cancer. But since about half of the world’s population is infected, and less than 1 percent of infected individuals develop cancer, other factors must contribute to gastric cancer risk.

Barbara Schneider, Ph.D., and colleagues are examining the role of epigenetic factors – modifications that alter gene expression, but do not affect the primary DNA sequence. They compared gastric biopsies from two Colombian populations – one with high risk of gastric cancer and one with lower risk – with similar prevalence of H. pylori infection.

In the Dec. 1 International Journal of Cancer, they report that regulatory regions (promoters) of two genes (RPRM and TWIST1) were more heavily modified (methylated) in the high-risk population compared to the low-risk population. Infection with more virulent bacterial strains was also associated with increased DNA methylation. The results suggest that DNA methylation could be a useful biomarker for determining gastric cancer risk.

For other research highlights from Vanderbilt University Medical Center laboratories, see ‘Aliquots‘ in the VUMC Reporter.