Dysbiosis Signature of Fecal Microbiota in Colorectal Cancer Patients

Abstract

The human gut microbiota is a complex system that is essential to the health of the host. Increasing evidence suggests that the gut microbiota may play an important role in the pathogenesis of colorectal cancer (CRC). In this study, we used pyrosequencing of the 16S rRNA gene V3 region to characterize the fecal microbiota of 19 patients with CRC and 20 healthy control subjects. The results revealed striking differences in fecal microbial population patterns between these two groups. Partial least-squares discriminant analysis showed that 17 phylotypes closely related to Bacteroides were enriched in the gut microbiota of CRC patients, whereas nine operational taxonomic units, represented by the butyrate-producing genera Faecalibacterium and Roseburia, were significantly less abundant. A positive correlation was observed between the abundance of Bacteroides species and CRC disease status (R = 0.462, P = 0.046 < 0.5). In addition, 16 genera were significantly more abundant in CRC samples than in controls, including potentially pathogenic Fusobacterium and Campylobacter species at genus level. The dysbiosis of fecal microbiota, characterized by the enrichment of potential pathogens and the decrease in butyrate-producing members, may therefore represent a specific microbial signature of CRC. A greater understanding of the dynamics of the fecal microbiota may assist in the development of novel fecal microbiome-related diagnostic tools for CRC.

Fusobacterium nucleatum associates with stages of colorectal neoplasia development, colorectal cancer and disease outcome

“…Of potential relevance in this context, we also found Fn load in the stool of CRC patients to be significantly higher than that of adenoma patients (p=0.0316) and also healthy control patients (p=0.0201), although we had a small number of stool samples from CRC patients available for analysis. Interestingly, a recent Chinese study examining faecal microbial communities in healthy and CRC groups observed a marked increase in the relative abundance of Fn in the CRC cancer cohort compared with the healthy control group [35].…”

Resilience of the Natural Phyllosphere Microbiota of the Grapevine to Chemical and Biological Pesticides

“…To detect significant differences in microbial abundances among treatments and growth conditions, ANOVA was applied using Tukey's test (␣ ϭ 0.05) (58,59). Spearman's rank correlations (P Ͻ 0.01) (60,61) were used to compare relative microbial abundances with the efficacy against downy mildew on leaf discs and with the environmental parameters of rainfall (mm), maximum, minimum, and mean temperatures (°C) at each location.…”

Rapid detection of nusG and fadA in Fusobacterium nucleatum by loop-mediated isothermal amplification

“…are enriched in CRC tissues relative to adjacent healthy tissues (Castellarin et al, 2012). For example, a Chinese study that analysed faecal microbial communities in healthy individuals and CRC patients identified a remarkable increase in Fusobacterium nucleatum counts in the CRC cohort compared with the healthy control group (Wu et al, 2013). Similarly, a North American study found that F. nucleatum was more abundant in stool samples from patients with CRC than in those from healthy subjects (Kostic et al, 2012(Kostic et al, , 2013.…”

“…Increasing evidence suggests that gut microbiota play an important role in the development of CRC (Wu et al, 2013). Fusobacterium spp., in particular, have been associated with human CRC, as confirmed by metagenomic analyses using whole-genome (Kostic et al, 2012), transcriptome (Kostic et al, 2012(Kostic et al, , 2013 and bacterial 16S ribosomal RNA sequencing (Marchesi et al, 2011;Kostic et al, 2012).…”