Basic Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Feb 14, 2020; 26(6): 614-626
Published online Feb 14, 2020. doi: 10.3748/wjg.v26.i6.614
Characterizing the composition of intestinal microflora by 16S rRNA gene sequencing
Wen-Jia Wang, You-Lian Zhou, Jie He, Zhi-Qiang Feng, Long Zhang, Xiao-Bo Lai, Jun-Xiao Zhou, Hong Wang
Wen-Jia Wang, You-Lian Zhou, Jie He, Zhi-Qiang Feng, Long Zhang, Xiao-Bo Lai, Jun-Xiao Zhou, Hong Wang, Department of Gastroenterology, Guangzhou Digestive Disease Center, Guangzhou First People’s Hospital, South China University of Technology, Guangzhou 510030, Guangdong Province, China
Author contributions: Wang WJ was responsible for sequencing and data analyses; Zhou YL and He J analyzed dates after sequencing; Feng ZQ, Zhang L and Lai XB collected specimens; Zhou JX contributed to the article and revised it; Wang H conceived the study and drafted the manuscript; Both authors approved the final version of the article.
Supported by Guangdong Provincial Department of Science and Technology, No. 2014A020212568; National Key Clinical Specialized Special Funds Programs of China, No. 2013544.
Institutional review board statement: The study was reviewed and approved by the Ethics Committee of the First People’s Hospital of Guangzhou.
Conflict-of-interest statement: The authors have no conflict of interest to declare.
Data sharing statement: No additional data are available.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Hong Wang, MD, PhD, Chief Physician, Department of Gastroenterology, Guangzhou Digestive Disease Center, Guangzhou First People’s Hospital, South China University of Technology, No. 1 Panfu Road, Yuexiu District, Guangzhou 510030, Guangdong Province, China. wong.hong@163.com
Received: August 13, 2019
Peer-review started: August 13, 2019
First decision: October 14, 2019
Revised: December 25, 2019
Accepted: January 11, 2020
Article in press: January 11, 2020
Published online: February 14, 2020
Abstract
BACKGROUND

This study determined the composition and diversity of intestinal microflora in patients with colorectal adenoma (CRA), which may provide precedence for investigating the role of intestinal microflora in the pathogenesis of colorectal tumors, the composition of intestinal microflora closely related to CRA, and further validating the possibility of intestinal flora as a biomarker of CRA.

AIM

To study the relationship between intestinal microflora and CRA.

METHODS

This is a prospective control case study from October 2014 to June 2015 involving healthy volunteers and patients with advanced CRA. High-throughput sequencing and bioinformatics analysis were used to investigate the composition and diversity of intestinal microflora in 36 healthy subjects and 49 patients with advanced CRA. Endpoints measured were operational taxonomic units of intestinal flora, as well as their abundance and diversity (α and β types).

RESULTS

In this study, the age, gender, body mass index, as well as location between controls and patients had no significant differences. The mucosa-associated gut microbiota diversity and bacterial distribution in healthy controls and colorectal adenomas were similar. The operational taxonomic unit, abundance, and α and β diversity were all reduced in patients with CRA compared to controls. At the phylum level, the composition of intestinal microflora was comparable between patients and controls, but the abundance of Proteobacteria was increased, and Firmicutes and Bacteroides were significantly decreased (P < 0.05). The increase in Halomonadaceae and Shewanella algae, and reduction in Coprococcus and Bacteroides ovatus, could serve as biomarkers of CRA. High-throughput sequencing confirms the special characteristics and diversity of intestinal microflora in healthy controls and patients with CRA.

CONCLUSION

The diversity of intestinal microflora was decreased in patients with CRA. An increase in Halomonadaceae and Shewanella algae are markers of CRA.

Keywords: 16S rDNA, Intestinal microflora, Advanced colorectal adenoma, Colorectal cancer, Biomarkers

Core tip: Colorectal adenomas (CRAs), the most important pre-cancerous lesions in colorectal cancer, have a close relationship with intestinal microflora. However, the mechanism is not clear. Early detection of CRA can effectively reduce the morbidity and mortality of colorectal cancer. This study analyzes the composition and diversity of intestinal microflora in patients with CRA through 16s rDNA gene sequencing. It was proven that the diversity of intestinal microflora in patients with CRA decreased, and that an increase in the number of Halomonadaceae and Shewanella algae may be biomarkers of CRA, which provides a basis for future research.