Changes in gut microbiota and plasma inflammatory factors across the stages of colorectal tumorigenesis: a case-control study

Abstract

BackgroundColorectal cancer (CRC) is a common malignant gastrointestinal tumor. In China, CRC is the 5th most commonly diagnosed cancer. The vast majority of CRC cases are sporadic and evolve with the adenoma-carcinoma sequence. There is mounting evidence indicating that gut microbiota and inflammation play important roles in the development of CRC although study results are not entirely consistent. In the current study, we investigated the changes in the CRC-associated bacteria and plasma inflammatory factors and their relationships based on data from a case-control study of Han Chinese. We included 130 initially diagnosed CRC patients, 88 advanced colorectal adenoma patients (A-CRA), 62 patients with benign intestinal polyps and 130 controls.ResultsFecal microbiota composition was obtained using 16S ribosomal DNA (16S rDNA) sequencing. PCOA analysis showed structural differences in microbiota among the four study groups (P = 0.001, Unweighted Unifrac). Twenty-four CRC-associated bacteria were selected by a two-step statistical method and significant correlations were observed within these microbes. CRC-associated bacteria were found to change with the degree of malignancy. Plasma C-reactive protein (CRP) and soluble tumor necrosis factor II (sTNFR-II) displayed significant differences among the four study groups and increased with adenoma-carcinoma sequence. The correlations of CRP and sTNFR-II with several CRC-associated microbes were also explored.ConclusionsCRC-associated species and plasma inflammatory factors tended to change along the adenoma-carcinoma sequence. Several CRC-associated bacteria were correlated with CRP and sTNFR-II. It is likely that gut microbiome and inflammation gradually form a microenvironment that is associated with CRC development.Electronic supplementary materialThe online version of this article (10.1186/s12866-018-1232-6) contains supplementary material, which is available to authorized users.

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

“…If the gut microbiota do contribute to the modelling of the TME via providing nutrients or immune modulation then from the data presented here, HCC and CRC have a very different TME. In addition, it can be seen from the Table 10 that HCC spawned from three (Greathouse et al, 2015) *Data taken from (Zhang et al, 2018). different etiologies may also have distinct differences in their TME.…”

Immune senescence and immune activation in elderly colorectal cancer patients

“…A relationship between commensal bacteria and intestinal carcinogenesis was first suggested in rodent models by Reddy et al in 1974 [19]. In recent studies, detailed microbial profiles gained by high-throughput analyses, like metagenomics sequencing and 16S rDNA sequencing, have revealed that bacteria are associated with CRC [20–23]. However, nothing was reported to our knowledge about cellular immune activation.…”

Microbiome and morbid obesity increase pathogenic stimulus diversity

“…However, the approach of the disruption of signaling homeostasis-induced crosstalk in the carcinogenesis paradigm "Epistemology of the origin of cancer" is strongly supported by the evidence provided within the various publications of this Special Issue and in terms of the microbiome as dysbiosis with changes in inflammation together with cancer development along the adenomacarcinoma sequence has been provided [54] without any mutation.…”