title: Invasive Fusobacterium nucleatum may play a role in the carcinogenesis of proximal colon cancer through the serrated neoplasia pathway.
abstract: The prevalence of invasive Fusobacterium nucleatum (Fn) within the serrated neoplasia pathway of the proximal colon has seldom been investigated. We examined the invasive Fn and bacterial biofilms in 35 proximal hyperplastic polyps (HPs), 33 sessile serrated adenomas (SSAs), 48 proximal colorectal cancers (CRCs) and 10 matched metastatic lymph nodes using 16S rRNA fluorescence in situ hybridization (FISH). Samples of normal mucosa, traditional adenomas (TAs), distal HPs, distal CRCs and matched lymph nodes with or without metastases were used as controls. The prevalence of invasive Fn within proximal HPs (65.7%) and SSAs (78.8%) were significantly higher than that of proximal TAs (28.9%) and distal TAs (24.4%; p < 0.05). Invasive Fn was detected in markedly more proximal CRCs (89.6%) than in distal CRCs (42.2%; p < 0.05). Moreover, invasive Fn was detected in a significantly higher proportion of matched metastatic lymph nodes (100%) than that within nonmetastatic lymph nodes (40.0%; p < 0.001). Bacterial biofilms were found on 52.1% of proximal CRCs, 55.6% of distal CRCs and 48.5% of SSAs. Biofilms were positive for Fn in 47.9% of proximal CRCs, 48.9% of distal CRCs and 27.3% of SSAs. However, the presence of Fn in biofilms was not related to invasive Fn within colorectal tissues (p = 0.415). Invasive Fn may play a role in the carcinogenesis of proximal colon developing via the serrated neoplasia pathway, but might have a less important role in the TA-carcinoma sequence. Bacterial biofilms may not contribute to the invasion of Fn into tumor tissues.
authors.affiliation: Department of Gastroenterology, The Affiliated Hospital of Luzhou Medical College, Sichuan, China.
authors.forename: Jiahui
authors.initials: J
authors.lastname: Yu
authors.affiliation: Department of Gastroenterology, The Affiliated Hospital of Luzhou Medical College, Sichuan, China.
authors.forename: Yongyu
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Gastroenterology, The Affiliated Hospital of Luzhou Medical College, Sichuan, China.
authors.forename: Xiangsheng
authors.initials: X
authors.lastname: Fu
authors.affiliation: Department of Gastroenterology, The Affiliated Hospital of Luzhou Medical College, Sichuan, China.
authors.forename: Xian
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Department of Gastroenterology, The Affiliated Hospital of Luzhou Medical College, Sichuan, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Peng
authors.affiliation: Department of Gastroenterology, The Affiliated Hospital of Luzhou Medical College, Sichuan, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Shi
authors.affiliation: Department of Gastroenterology, The Affiliated Hospital of Luzhou Medical College, Sichuan, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Chen
authors.affiliation: Department of Gastroenterology, The Affiliated Hospital of Luzhou Medical College, Sichuan, China.
authors.forename: Yaxin
authors.initials: Y
authors.lastname: Wu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002471:Cell Transformation, Neoplastic / Q000378:metabolism; D003110:Colonic Neoplasms / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000378:metabolism*; D005260:Female; D005674:Fusobacterium Infections / Q000150:complications* / Q000382:microbiology* / Q000473:pathology; D016967:Fusobacterium nucleatum / Q000472:pathogenicity / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D015398:Signal Transduction
keywords: Fusobacterium nucleatum; biofilms; colorectal cancer; sessile serrated adenoma