Sporadic colorectal cancer (CRC) results from accumulated DNA mutations in colonic epithelial cells but the factors inducing the causative DNA mutations are unclear. One prime local consideration is the microbiota but little is known about how the microbiota may influence colon carcinogenesis. To further understand the relationship between the microbiota and the colonic epithelium in CRC hosts and non-cancer hosts, we studied the microbiota organization in Carnoy's fixed tissues that preserve the mucus layer of the colonic epithelium and the community composition through microbiome profiling. Unexpectedly, we identified a broad regional change in microbiota organization on colon tissues of the CRC host with invasive polymicrobial bacterial biofilms found commonly on both surgically-resected tumors and normal tissue from the proximal colon. Bacterial biofilms were associated with changes in tissue biology predicted to contribute to colon carcinogenesis. In contrast, the non-tumor host colon epithelial samples did not reveal geographic localization of biofilm formation. High throughput sequencing did not reveal consistent bacterial community membership associated with tumors, regardless of biofilm status. Colon mucosal biofilm detection may contribute to risk for development of sporadic CRC.
Citation Format: Cynthia L. Sears. Microbiota associations in colon cancer. [abstract]. In: Proceedings of the AACR Special Conference: Tumor Immunology and Immunotherapy: A New Chapter; December 1-4, 2014; Orlando, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2015;3(10 Suppl):Abstract nr IA13.
- ©2015 American Association for Cancer Research.