Gut microbiota of patients with different subtypes of gastric cancer and gastrointestinal stromal tumors

Virinder Sarhadi,Tiina Karla,Hilpi Rautelin,Arto Kokkola,Pauli Puolakkainen,Leo Lahti,Milja Tikkanen,Binu Mathew,Sakari Knuutila

doi:10.1186/s13099-021-00403-x

Abstract

BackgroundGastric adenocarcinoma is associated with H. pylori infection and inflammation that can result in the dysbiosis of gastric microbiota. The association of intestinal microbiota with gastric adenocarcinoma subtypes or with gastric gastrointestinal stromal tumors (GIST) is however not well known. Therefore, we performed 16S rRNA gene sequencing on DNA isolated from stool samples of Finnish patients and controls to study differences in microbiota among different histological subtypes of gastric adenocarcinoma, gastric GIST and healthy controls.ResultsWe found that gut microbiota alpha diversity was lowest in diffuse adenocarcinoma patients, followed by intestinal type and GIST patients, although the differences were not significant compared to controls. Beta-diversity analysis however showed significant differences in microbiota composition for all subtypes compared to controls. Significantly higher abundance of Enterobacteriaceae was observed in both adenocarcinoma subtypes, whereas lower abundance of Bifidobacteriaceae was seen only in diffuse adenocarcinoma and of Oscillibacter in intestinal adenocarcinoma. Both GIST and adenocarcinoma patients had higher abundance of Enterobacteriaceae and lower abundance of Lactobacillaceae and Oscillibacter while lower abundance of Lachnoclostridium, Bifidobacterium, Parabacteroides and Barnesiella was seen only in the adenocarcinoma patients.ConclusionsOur analysis shows association of higher Enterobacteriaceae abundance with all types of gastric tumors. Therefore it could be potentially useful as a marker of gastric malignancies. Lower gut microbiota diversity might be indicative of poorly differentiated, invasive, advanced or aggressive tumors and could possibly be a prognostic marker for gastric tumors.

Highlights

Gastric adenocarcinoma is associated with H. pylori infection and inflammation that can result in the dysbiosis of gastric microbiota
Microbiota diversity Alpha‐diversity Gut microbiota richness and diversity were studied for different gastric cancer groups and the results (Fig. 1) showed lower microbiota richness and diversity in patients with gastric adenocarcinoma and gastric gastrointestinal stromal tumors (GIST) patients compared to controls
No significant differences were observed between adenocarcinoma and GIST patients for richness (Fig. 1a) or diversity (Fig. 1b)

Summary

Introduction

Gastric adenocarcinoma is associated with H. pylori infection and inflammation that can result in the dysbiosis of gastric microbiota. The association of intestinal microbiota with gastric adenocarcinoma subtypes or with gastric gastrointestinal stromal tumors (GIST) is not well known. We performed 16S rRNA gene sequencing on DNA isolated from stool samples of Finnish patients and controls to study differences in microbiota among different histological subtypes of gastric adenocarcinoma, gastric GIST and healthy controls. Gastrointestinal stromal tumors (GIST) are rare and are very different from gastric adenocarcinoma. They are commonly located in stomach, they can be present in other parts of the gastrointestinal tract. They originate from stromal cells and have KIT or PDGRAmutations [reviewed in 10]

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