High occurrence of Fusobacterium nucleatum and Clostridium difficile in the intestinal microbiota of colorectal carcinoma patients

Abstract

Colorectal carcinoma is considered the fourth leading cause of cancer deaths worldwide. Several microorganisms have been associated with carcinogenesis, including Enterococcus spp., Helicobacter pylori, enterotoxigenic Bacteroides fragilis, pathogenic E. coli strains and oral Fusobacterium. Here we qualitatively and quantitatively evaluated the presence of oral and intestinal microorganisms in the fecal microbiota of colorectal cancer patients and healthy controls. Seventeen patients (between 49 and 70 years-old) visiting the Cancer Institute of the Sao Paulo State were selected, 7 of whom were diagnosed with colorectal carcinoma. Bacterial detection was performed by qRT-PCR. Although all of the tested bacteria were detected in the majority of the fecal samples, quantitative differences between the Cancer Group and healthy controls were detected only for F. nucleatum and C. difficile. The three tested oral microorganisms were frequently observed, suggesting a need for furthers studies into a potential role for these bacteria during colorectal carcinoma pathogenesis. Despite the small number of patients included in this study, we were able to detect significantly more F. nucleatum and C. difficile in the Cancer Group patients compared to healthy controls, suggesting a possible role of these bacteria in colon carcinogenesis. This finding should be considered when screening for colorectal cancer.

<i>Fusobacterium nucleatum</i>—The Cause of Human Colorectal Cancer

“…The data as published by Fukugaiti et al [31] do support our Null hypothesis that an infection by Fusobacterium is a conditio sine qua non of colorectal cancer. In other words, without an infection by Fusobacterium no colorectal cancer.…”

“…On the whole, the results of this study reflect the main features of other studies. The studies of Fukugaiti et al [31], Vogtmann et al [32] (two sided), Li et al [33], Amitay et al [34], Eklöf et al [35], where able to provide evidence that Fusobacterium is a necessary condition, a conditio sine qua non, of colon cancer. Con-sistent with this finding, the current study using data published by Ahn et al [30], Vogtmann et al [32] documented a significant cause effect relationship between Fusobacterium and colon cancer while the studies of Li et al [33], Amitay et al [34], Eklöf et al [35] were able to provide evidence of a highly significant cause effect relationship between Fusobacterium and colon cancer.…”

“…Fukugaiti et al [31] investigated seventeen patients, 7 of whom were diagnosed with colorectal carcinoma, to evaluate the presence of Fusobacterium nucleatum and other intestinal microorganisms in the fecal microbiota of colorectal cancer patients (n = 7) and healthy controls (n = 10). Fecal samples were collected two days before colonoscopy while patients who had taken antibiotics or with any systemic infection were excluded from the study.…”

“…The data of Fukugaiti et al [31] of an infection by Fusobacterium and colorectal cancer are viewed in the 2 × 2 table (Table 3). The proportion of successes Table 25.…”

Mechanistic and Technical Challenges in Studying the Human Microbiome and Cancer Epidemiology

“…[14][15][16] Differences in microbiota composition exist in different organ sites, and colon microbiota has been studied the most in cancer development. 17,18 Colonic mucosa are in constant direct contact with microbiota and substances (eg, different metabolites and toxins, superoxide radicals) produced by them. Effects of diet on colon cancer development have been studied by several investigators.…”