Abstract

Pancreatic Ductal Adenocarcinoma (PDAC), a cancer of the pancreatic duct, has a 5-year survival rate of just 9%. In almost 80% of diagnosed cases, conventional methods of detection that could aid in earlier diagnosis fail to detect tumors due to the pancreas’ deep-seated placement in the gut. Thus, innovative markers that can be developed as signatures for early detection of pancreatic cancer is an active area of research. A commonly used mouse model that mimics PDAC’s rapid growth , PKT (Pdxcre , KRasG12DTGFBRII-/-) was used to determine the microbial and accompanying microbial metabolite signatures during pancreatic tumor development and progression during  a 10-week period. Fecal samples (n=10) were collected for analysis and shotgun metagenomics was performed on the bacterial DNA isolated. Sequence data was organized based on phylum, class and species of bacteria and quantified based on their abundance. Enrichment of Firmicutes and Verrucomicrobia phyla when compared to their levels in Collection 1 increased as early as 5 weeks (Collection 2), and became less abundant at Week 6 (Collection 3) onward. Interestingly, bacteria belonging to Actinobacteria phyla became abundant late in tumor progression (12 weeks of age/Collection 8), indicating there was a differential change in bacterial phyla over time. Classes Verrumicrobiae, Clostridia and Erysipelotrichia all exhibit relative abundance in early stages (collections 1-5). Future analysis will investigate the metabolomic signature and its putative relationship with the microbiome as a diagnostic in tumor progression.