Biomaterial Database

Colon Tumors in Enterotoxigenic Bacteroides fragilis (ETBF)-Colonized Mice Do Not Display a Unique Mutational Signature but Instead Possess Host-Dependent Alterations in the APC Gene. 2022

Jawara Allen, and Axel Rosendahl Huber, and Cayetano Pleguezuelos-Manzano, and Jens Puschhof, and Shaoguang Wu, and Xinqun Wu, and Charelle Boot, and Aurelia Saftien, and Heather M O'Hagan, and Hao Wang, and Ruben van Boxtel, and Hans Clevers, and Cynthia L Sears

Department of Medicine, Johns Hopkins University School of Medicinegrid.471401.7, Baltimore, Maryland, USA.

Enterotoxigenic Bacteroides fragilis (ETBF) is consistently found at higher frequency in individuals with sporadic and hereditary colorectal cancer (CRC) and induces tumorigenesis in several mouse models of CRC. However, whether specific mutations induced by ETBF lead to colon tumor formation has not been investigated. To determine if ETBF-induced mutations impact the Apc gene, and other tumor suppressors or proto-oncogenes, we performed whole-exome sequencing and whole-genome sequencing on tumors isolated after ETBF and sham colonization of Apcmin/+ and Apcmin/+Msh2VC mice, as well as whole-genome sequencing of organoids cocultured with ETBF. Our results indicate that ETBF-induced tumor formation results from loss of heterozygosity (LOH) of Apc, unless the mismatch repair system is disrupted, in which case, tumor formation results from new acquisition of protein-truncating mutations in Apc. In contrast to polyketide synthase-positive Escherichia coli (pks+ E. coli), ETBF does not produce a unique mutational signature; instead, ETBF-induced tumors arise from errors in DNA mismatch repair and homologous recombination DNA damage repair, established pathways of tumor formation in the colon, and the same genetic mechanism accounting for sham tumors in these mouse models. Our analysis informs how this procarcinogenic bacterium may promote tumor formation in individuals with inherited predispositions to CRC, such as Lynch syndrome or familial adenomatous polyposis (FAP). IMPORTANCE Many studies have shown that microbiome composition in both the mucosa and the stool differs in individuals with sporadic and hereditary colorectal cancer (CRC). Both human and mouse models have established a strong association between particular microbes and colon tumor induction. However, the genetic mechanisms underlying putative microbe-induced colon tumor formation are not well established. In this paper, we applied whole-exome sequencing and whole-genome sequencing to investigate the impact of ETBF-induced genetic changes on tumor formation. Additionally, we performed whole-genome sequencing of human colon organoids exposed to ETBF to validate the mutational patterns seen in our mouse models and begin to understand their relevance in human colon epithelial cells. The results of this study highlight the importance of ETBF colonization in the development of sporadic CRC and in individuals with hereditary tumor conditions, such as Lynch syndrome and familial adenomatous polyposis (FAP).

UI	MeSH Term	Description	Entries
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D011125	Adenomatous Polyposis Coli	A polyposis syndrome due to an autosomal dominant mutation of the APC genes (GENES, APC) on CHROMOSOME 5. The syndrome is characterized by the development of hundreds of ADENOMATOUS POLYPS in the COLON and RECTUM of affected individuals by early adulthood.	Polyposis Coli, Familial,Polyposis Syndrome, Familial,Adenomatous Polyposis Coli, Familial,Adenomatous Polyposis of the Colon,Familial Adenomatous Polyposis,Familial Adenomatous Polyposis Coli,Familial Adenomatous Polyposis of the Colon,Familial Intestinal Polyposis,Familial Multiple Polyposi,Familial Multiple Polyposis,Familial Multiple Polyposis Syndrome,Familial Polyposis Coli,Familial Polyposis Syndrome,Familial Polyposis of the Colon,Hereditary Polyposis Coli,Myh-Associated Polyposis,Polyposis Coli,Polyposis, Adenomatous Intestinal,Adenomatous Intestinal Polyposes,Adenomatous Intestinal Polyposis,Adenomatous Polyposes, Familial,Adenomatous Polyposis Colus,Adenomatous Polyposis, Familial,Coli, Adenomatous Polyposis,Coli, Familial Polyposis,Coli, Hereditary Polyposis,Coli, Polyposis,Colus, Adenomatous Polyposis,Colus, Familial Polyposis,Colus, Hereditary Polyposis,Colus, Polyposis,Familial Adenomatous Polyposes,Familial Intestinal Polyposes,Familial Multiple Polyposes,Familial Multiple Polyposus,Familial Polyposis Colus,Familial Polyposis Syndromes,Hereditary Polyposis Colus,Intestinal Polyposes, Familial,Intestinal Polyposis, Adenomatous,Intestinal Polyposis, Familial,Multiple Polyposes, Familial,Multiple Polyposi, Familial,Multiple Polyposis, Familial,Multiple Polyposus, Familial,Myh Associated Polyposis,Myh-Associated Polyposes,Polyposes, Familial Adenomatous,Polyposes, Familial Multiple,Polyposes, Myh-Associated,Polyposi, Familial Multiple,Polyposis Coli, Adenomatous,Polyposis Coli, Hereditary,Polyposis Colus,Polyposis Colus, Adenomatous,Polyposis Colus, Familial,Polyposis Colus, Hereditary,Polyposis, Familial Adenomatous,Polyposis, Familial Multiple,Polyposis, Myh-Associated,Polyposus, Familial Multiple
D003106	Colon	The segment of LARGE INTESTINE between the CECUM and the RECTUM. It includes the ASCENDING COLON; the TRANSVERSE COLON; the DESCENDING COLON; and the SIGMOID COLON.	Appendix Epiploica,Taenia Coli,Omental Appendices,Omental Appendix,Appendices, Omental,Appendix, Omental
D003110	Colonic Neoplasms	Tumors or cancer of the COLON.	Cancer of Colon,Colon Adenocarcinoma,Colon Cancer,Cancer of the Colon,Colon Neoplasms,Colonic Cancer,Neoplasms, Colonic,Adenocarcinoma, Colon,Adenocarcinomas, Colon,Cancer, Colon,Cancer, Colonic,Cancers, Colon,Cancers, Colonic,Colon Adenocarcinomas,Colon Cancers,Colon Neoplasm,Colonic Cancers,Colonic Neoplasm,Neoplasm, Colon,Neoplasm, Colonic,Neoplasms, Colon
D003123	Colorectal Neoplasms, Hereditary Nonpolyposis	A group of autosomal-dominant inherited diseases in which COLON CANCER arises in discrete adenomas. Unlike FAMILIAL POLYPOSIS COLI with hundreds of polyps, hereditary nonpolyposis colorectal neoplasms occur much later, in the fourth and fifth decades. HNPCC has been associated with germline mutations in mismatch repair (MMR) genes. It has been subdivided into Lynch syndrome I or site-specific colonic cancer, and LYNCH SYNDROME II which includes extracolonic cancer.	Colon Cancer, Familial Nonpolyposis, Type 1,Colorectal Cancer, Hereditary Nonpolyposis, Type 1,Familial Nonpolyposis Colon Cancer Type 1,Hereditary Nonpolyposis Colorectal Cancer,Hereditary Nonpolyposis Colorectal Cancer Type 1,Hereditary Nonpolyposis Colorectal Neoplasms,Lynch Syndrome,Colon Cancer, Familial Nonpolyposis,Colorectal Cancer Hereditary Nonpolyposis,Familial Nonpolyposis Colon Cancer,Hereditary Nonpolyposis Colon Cancer,Lynch Cancer Family Syndrome I,Lynch Syndrome I,Syndrome, Lynch
D004195	Disease Models, Animal	Naturally-occurring or experimentally-induced animal diseases with pathological processes analogous to human diseases.	Animal Disease Model,Animal Disease Models,Disease Model, Animal
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001424	Bacterial Infections	Infections by bacteria, general or unspecified.	Bacterial Disease,Bacterial Infection,Infection, Bacterial,Infections, Bacterial,Bacterial Diseases
D001441	Bacteroides fragilis	Gram-negative bacteria occurring in the lower intestinal tracts of man and other animals. It is the most common species of anaerobic bacteria isolated from human soft tissue infections.