"Beyond mutation: bacterial carcinogenesis through niche remodeling"

Chronic Helicobacter pylori infection represents the major risk factor for stomach cancer, the third leading cause of cancer death globally. Yet most infected individuals remain asymptomatic, suggesting a more symbiotic relationship of this obligate human stomach microbiome constituent. I will discuss recent murine model studies exploring how H. pylori remodels the stomach tissue environment to simultaneously promote long term bacterial persistence and preneoplastic progression. A second set of experiments investigates the selective pressures on H. pylori imposed by the changing tissue environment revealed through whole genome analysis and extensive phenotyping of a culture collection from a single individual that progressed from duodenal ulcer disease to chronic atrophic gastritis over a 6 year period.