Alterations of the Predominant Fecal Microbiota and Disruption of the Gut Mucosal Barrier in Patients with Early-Stage Colorectal Cancer

Abstract

Growing evidence indicated that the gut microbiota was the intrinsic and essential component of the cancer microenvironment, which played vital roles in the development and progression of colorectal cancer (CRC). In our present study, we investigated the alterations of fecal abundant microbiota with real-time quantitative PCR and the changes of indicators of gut mucosal barrier from 53 early-stage CRC patients and 45 matched healthy controls. We found that the traditional beneficial bacteria such as Lactobacillus and Bifidobacterium decreased significantly and the carcinogenic bacteria such as Enterobacteriaceae and Fusobacterium nucleatum were significantly increased in CRC patients. We also found gut mucosal barrier dysfunction in CRC patients with increased levels of endotoxin (LPS), D-lactate, and diamine oxidase (DAO). With Pearson’s correlation analysis, D-lactate, LPS, and DAO were correlated negatively with Lactobacillus and Bifidobacterium and positively with Enterobacteriaceae and F. nucleatum. Our present study found dysbiosis of the fecal microbiota and dysfunction of the gut mucosal barrier in patients with early-stage CRC, which implicated that fecal abundant bacteria and gut mucosal barrier indicators could be used as targets to monitor the development and progression of CRC in a noninvasive and dynamic manner.

The Intestinal Microbiota and Colorectal Cancer

“…Fusobacterium nucleatum (F. nucleatum) is enriched in human colorectal adenomas and carcinomas (45,57) and may contribute to disease progression from adenoma to cancer (46). In our recent study, F. nucleatum was significantly increased in patients with early-stage CRC (49). The presence of F. nucleatum in CRC tissues indicated a worse prognosis (47,48).…”

Gut microbiota alterations are distinct for primary colorectal cancer and hepatocellular carcinoma

“…Protein & (Xie et al, 2017) Gut microbiota in CRC and HCC producers (i.e., Lachnospira multipara and Eubacterium eligens) and Bifidobacterium longum were depleted with the progression of CRC. Like HCC, there are changes in the composition of the microbiota as the disease progresses through different stages (Liu et al, 2020).…”

Detection of Fusobacterium nucleatum in feces and colorectal mucosa as a risk factor for colorectal cancer: a systematic review and meta-analysis

“…In seven studies, cases and controls were matched for two to four variables, including age, gender, body mass index, ethnicity, and the time period of sample collection [42,47,50,51,53,54,57,62]. There were 13 studies that excluded subjects with reported antibiotic use in the last month, or in the last 3 months or 6 months, and 11 studies that excluded patients previously diagnosed with IBD.…”