# H. Pylori Relationship to Digestive Diseases and Cancer

> **NIH NIH R01** · VANDERBILT UNIVERSITY MEDICAL CENTER · 2024 · $493,103

## Abstract

Project Summary
Helicobacter pylori is the strongest known risk factor for gastric cancer and interactions between this chronic
pathogen and immune cells dysregulate gastric epithelial signaling pathways that influence carcinogenesis.
One H. pylori oncogenic determinant is the cag type IV secretion system (TFSS) which translocates pro-
inflammatory effectors, such as CagA, into epithelial cells. In studies supported by R01 CA 77955, we
demonstrated that the cag TFSS can also translocate peptidoglycan, which is sensed by the pattern
recognition receptor (PRR), NOD1. However, negative regulation of certain PRRs by chronic pathogens can
increase pro-inflammatory responses and disease, and we have also demonstrated that prolonged H. pylori
infection activates a NOD1-dependent negative feedback loop in gastric epithelial cells, leading to increased
NF-kB activation. These data have driven our recent efforts to more broadly define the consequences of NOD1
suppression using human samples and rodent models; these findings demonstrate that 1) NOD1 expression is
reduced in H. pylori-infected gastric cancer tissue compared with uninvolved tissue, 2) genetic deficiency of
Nod1 significantly increases H. pylori-induced carcinogenesis and expression of the Th9 cytokine IL-9, a key
effector of epithelial damage and inflammation, 3) H. pylori up-regulates expression of the IL-9 receptor in ex
vivo epithelial gastroids, and 4) treatment of H. pylori-infected gastroids with IL-9 leads to enhanced cell
survival within the context of Nod1 deficiency. We have established innovative models (primary
gastroid:macrophage:T cell co-culture systems) that more closely recapitulate the infected gastric niche to
demonstrate that H. pylori upregulates IL-9 production in a cag TFSS-dependent manner. Finally, we have
gastric tissue and sera from a unique longitudinal human cohort in Colombia that includes persons who either
progressed to irreversible premalignant gastric lesions or remained stable, which will provide critical clinical
validation of our mechanistic studies. Our hypothesis is that suppression of NOD1 signaling contributes
to the augmentation in cancer risk conferred by H. pylori by deploying immune responses (Th9) with
carcinogenic potential. We will test this hypothesis via these Specific Aims:
1. Utilize novel rodent models and ex vivo systems to define IL-9-dependent host responses linked to H. pylori-
induced disease progression
2. Validate and extend mechanistic studies focused on H. pylori, IL-9, and NOD1 using samples and H. pylori
strains isolated from persons who did or did not progress towards gastric cancer
3. Use targeted approaches to inhibit IL-9 immune responses within the context of H. pylori infection

## Key facts

- **NIH application ID:** 10833204
- **Project number:** 5R01CA077955-28
- **Recipient organization:** VANDERBILT UNIVERSITY MEDICAL CENTER
- **Principal Investigator:** RICHARD M. PEEK
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $493,103
- **Award type:** 5
- **Project period:** 1997-09-30 → 2028-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10833204

## Citation

> US National Institutes of Health, RePORTER application 10833204, H. Pylori Relationship to Digestive Diseases and Cancer (5R01CA077955-28). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10833204. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*
