Characteristics Of Intestinal Microbiota Composition In Gastric Cancer Patients From Shanxi Province

Objective:The aims were to investigate the characteristics of intestinal microbiota composition in gastric cancer patients from Shanxi Province and correlations between the intestinal microbiota and cellular immunity.Methods:Fecal samples were collected from 116 gastric cancer patients and 88 healthy controls from Shanxi Province,China.The intestinal microbiota was investigated by 16S rRNA gene sequencing.Peripheral blood samples were also collected from the 66 gastric cancer patients and 46 healthy controls.The populations of peripheral T lymphocyte subpopulations and NK cells were analyzed by flow cytometry.Results:The intestinal microbiota in gastric cancer patients was characterized by increased species richness,decreased butyrate-producing bacteria,and the enrichment of other symbiotic bacteria,especially Lactobacillus,Escherichia and Klebsiella.Lactobacillus and Lachnospira were key species in the network of gastric cancer-associated bacterial genera.The combination of the genera Lachnospira,Lactobacillus,Streptococcus,Veillonella and Tyzzerella₃ showed good performance in distinguishing gastric cancer patients from healthy controls.There was no significant difference in enterotype distribution between healthy controls and gastric cancer patients.The percentage of CD3⁺T cells was positively correlated with the abundance of Lactobacillus and Streptococcus,and CD3⁺T cells,CD4⁺T cells and NK cells were associated with Lachnospiraceae taxa.Conclusion:Our study revealed a dysbiotic intestinal microbiota in gastric cancer patients.The abundance of some intestinal bacterial genera was correlated with the population of peripheral immune cells.