Enterotoxigenic Bacteroides fragilis infection exacerbates tumorigenesis in AOM/DSS mouse model

• Published in: International journal of medical sciences Vol. 17; no. 2; pp. 145 - 152
• Main Authors: Hwang, Soonjae, Lee, Chang Gun, Jo, Minjeong, Park, Chan Oh, Gwon, Sun-Yeong, Hwang, Samnoh, Yi, Hye Chin, Lee, So-Yeon, Eom, Yong-Bin, Karim, Baktiar, Rhee, Ki-Jong
• Format: Journal Article
• Language: English
• Published: Australia Ivyspring International Publisher Pty Ltd 2020; Ivyspring International Publisher
• Subjects: Bacteria; Colorectal cancer; Cytokines; Drinking water; Genes; Infections; Inflammatory bowel disease; Large intestine; Mutation; Polyps; Research Paper; Tumorigenesis; United States > US; Germany; ETBF; colorectal cancer; inflammation; azoxymethane; dextran sulfate sodium
• ISSN: 1449-1907; 1449-1907
• DOI: 10.7150/ijms.38371

The azoxymethane (AOM)/dextran sulfate sodium (DSS) murine model is commonly used to study colitis-associated cancer. The human commensal bacterium, enterotoxigenic
(ETBF) secretes the
toxin (BFT) which is necessary and sufficient to cause colitis. We report that BALB/c mice infected with WT-ETBF and administered three cycles of AOM/DSS developed numerous, large-sized polyps predominantly in the colorectal region. In addition, AOM/DSS-treated BALB/c mice orally inoculated with wild-type nontoxigenic
(WT-NTBF) overexpressing
(rETBF) developed numerous polyps whereas mice infected with WT-NTBF overexpressing a biologically inactive
(rNTBF) did not promote polyp formation. Unexpectedly, the combination of AOM+ETBF did not induce polyp formation whereas ETBF+DSS did induce polyp development in a subset of BALB/c mice. In conclusion, WT-ETBF promoted polyp development in AOM/DSS murine model with increased colitis in BALB/c mice. The model described herein provides an experimental platform for understanding ETBF-induced colonic tumorigenesis and studying colorectal cancer in wild-type mice.