Exploring changes in metabolites and fecal microbiota of advanced gastric cancer based on plasma metabolomics and 16S rDNA sequencing.

[UNLABELLED] Metabolomics and 16S rDNA sequencing have shown great potential in elucidating complex mechanisms associated with diseases. Currently, there is little research on the omics of gastric cancer and it lacks effective biomarkers.

[OBJECTIVE] Based on plasma metabolomics and 16S rDNA sequencing to evaluate the changes in metabolites and fecal microbiota of advanced gastric cancer.

[METHOD] Firstly, plasma metabolomics was used to screen for differential metabolites and metabolic pathways in gastric cancer. Then, 16S rDNA sequencing was performed on fecal samples to study the differential intestinal microbiota in gastric cancer patients. Finally, conduct a correlation analysis between them.

[RESULT] A total of 152 differential metabolites were identified, and we screened 10 of them. All metabolites were enriched into 42 differential metabolic pathways, of which 13 have P values less than 0.05. 16S rDNA sequencing showed significant differences in 4 microbial communities at the phylum level. There are significant differences in 23 communities at the genus level. We focus on Lactobacillales, Lactobacillus, Streptococcus, Veillonella, Bacilli and Megasphaera. Correlation analysis shows that the intestinal microbiota and plasma metabolites jointly affect the occurrence and development of gastric cancer.

[CONCLUSION] For the first time, we comprehensively used plasma metabolomics and 16S rDNA sequencing to reveal the changes and correlations between metabolites and intestinal microbiota in advanced gastric cancer. We have discovered new potential biomarkers for gastric cancer. This deepens our understanding of the physiological and pathological mechanisms of advanced gastric cancer and helps to improve the diagnosis and treatment of advanced gastric cancer.