Summary
H. pylori-negative MALT lymphoma patients exhibited altered gastric mucosal microbial compositions, suggesting that altered microbiota might be involved in the pathogenesis of H. pylori-negative MALT lymphoma.
Original Article
Gastric microbiota in patients with Helicobacter pylori-negative gastric MALT lymphoma
Medicine
Tanaka, Takahide MD; Matsuno, Yuichi MD, PhD; Torisu, Takehiro MD, PhD,∗; Shibata, Hiroki PhD; Hirano, Atsushi MD, PhD; Umeno, Junji MD, PhD; Kawasaki, Keisuke MD, PhD; Fujioka, Shin MD, PhD; Fuyuno, Yuta MD, PhD; Moriyama, Tomohiko MD, PhD; Esaki, Motohiro MD, PhD; Kitazono, Takanari MD, PhD
Abstract
To investigate the mucosal microbiota in the stomach of patients with Helicobacter pylori-negative mucosa-associated lymphoid tissue (MALT) lymphoma by means of metagenomic analysis.
Although some gastric MALT lymphomas are associated with the presence of H. pylori, other gastric MALT lymphomas occur independently of H. pylori infection. The pathogenesis of H. pylori-negative MALT lymphoma remains unclear.
Mucosal biopsy specimens were collected from the gastric body from 33 MALT lymphoma patients with gastric lesions, including both H. pylori-infection naïve patients and posteradication patients, as well as 27 control participants without H. pylori infection or cancer. Subsequently, the samples were subjected to 16S rRNA gene sequencing. Quantitative insights into microbial ecology, linear discriminant analysis effect size, and phylogenetic investigation of communities by reconstruction of unobserved states softwares were used to analyze the participants’ microbiota.
H. pylori-negative MALT lymphoma patients had significantly lower alpha diversity (P = .04), compared with control participants. Significant differences were evident in the microbial composition (P = .04), as determined by comparison of beta diversity between the 2 groups. Taxonomic composition analysis indicated that the genera Burkholderia and Sphingomonas were significantly more abundant in MALT lymphoma patients, while the genera Prevotella and Veillonella were less abundant. Functional microbiota prediction showed that the predicted gene pathways “replication and repair,” “translation,” and “nucleotide metabolism” were downregulated in MALT lymphoma patients.
H. pylori-negative MALT lymphoma patients exhibited altered gastric mucosal microbial compositions, suggesting that altered microbiota might be involved in the pathogenesis of H. pylori-negative MALT lymphoma.
Acknowledgment
We thank Ryan Chastain-Gross, PhD, from Edanz Group (https://en-author-services.edanzgroup.com/ac) for editing a draft of this manuscript.
Author contributions
Takahide Tanaka, Takehiro Torisu, and Takanari Kitazono designed this study. Takahide Tanaka, Yuichi Matsuno, Junji Umeno, Keisuke Kawasaki, Shin Fujioka, and Yuta Fuyuno collected the mucosal biopsies. Takahide Tanaka, Atsushi Hirano, and Hiroki Shibata performed the experiments. Takahide Tanaka, Takehiro Torisu, Motohiro Esaki, and Takanari Kitazono drafted the manuscript.
Conceptualization: Takahide Tanaka, Takehiro Torisu, Atsushi Hirano.
Data curation: Takahide Tanaka.
Formal analysis: Takahide Tanaka, Hiroki Shibata.
Investigation: Takahide Tanaka, Yuichi Matsuno, Atsushi Hirano.
Methodology: Takahide Tanaka, Takehiro Torisu, Hiroki Shibata, Atsushi Hirano.
Project administration: Takahide Tanaka.
Resources: Takahide Tanaka, Junji Umeno, Keisuke Kawasaki, Shin Fujioka, Yuta Fuyuno, Tomohiko Moriyama.
Software: Takahide Tanaka.
Supervision: Takehiro Torisu, Takanari Kitazono.
Validation: Takahide Tanaka.
Visualization: Takahide Tanaka.
Writing – original draft: Takahide Tanaka.
Writing – review & editing: Yuichi Matsuno, Takehiro Torisu, Motohiro Esaki.