Abstract 2176: Differences in gut microbial composition alter pancreatic tumorigenesis

Abstract

Abstract Pancreatic ductal adenocarcinoma (PDAC) is predicted to become the second leading cause of cancer-related deaths by 2030, and currently has a 5-year survival rate of roughly 10%. With long-term survival rates in patients being exceedingly low, understanding what factors delineate survival is imperative. When comparing spontaneous transgenic mouse models of pancreatic cancer housed in geographically distinct vivaria, regardless of a common lineage, we observed drastically different phenotype states in the respective locations. We hypothesize that the gut microbiome results in different gene expression profiles, leading to alterations in pancreatic tumorigenesis. Using various sequencing techniques, including 16s rRNA and RNA sequencing of the gut, we identified unique signatures at these respective institutions. Subsequent fecal microbiota transplantation and single bacterial species colonization experiments were performed to evaluate the ability of microbiomes/specific microbiota to alter the rate of tumorigenesis. In addition to probing the gut microbiome, circulating metabolites from individual mice were quantified, and correlated to phenotype state. Following identification of potentially tumorigenic bacterially derived metabolites, single bacteria colonization experiments were utilized to determine the downstream effects of identified metabolites as well as the ability of directly altering the metabolic landscape to drive tumorigenesis. Additionally, murine derived pancreatic cancer cells were exposed to both identified bacteria alone or bacterially produced metabolite and analyzed by metrics such as proliferation and relative expression of transcription factors associated with cancer development in vitro. Taken together, these data demonstrate the ability of distinct gut microbiomes to directly alter the metabolic landscape in mice, thus differentially altering the progression of pancreatic lesions. By better understanding the factors that stratify survivorship, we can begin to employ clinically actionable methodologies in the treatment or prevention of pancreatic cancer. Citation Format: Rian M. Howell, Jose Enriquez Ortiz, Olivia Le Roux, Vidhi Chandra, Le Li, Pratip K. Bhattacharya, Florencia McAllister. Differences in gut microbial composition alter pancreatic tumorigenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2176.