AUTHOR=Zhang Peng , Xu Jianfei , Zhou Yanbing 

TITLE=The relationship between gastric microbiome features and responses to neoadjuvant chemotherapy in gastric cancer

JOURNAL=Frontiers in Microbiology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2024.1357261

DOI=10.3389/fmicb.2024.1357261

ISSN=1664-302X

ABSTRACT=<sec id="sec1"><title>Background</title><p>Emerging evidence demonstrates that the gastrointestinal microbiome has the potential to be a biomarker in neoadjuvant chemoradiotherapy for colorectal cancer (CRC). Yet studies on the impact of the gastric microbiome (GM) on the response to neoadjuvant chemotherapy (NACT) are still scarce.</p></sec><sec id="sec2"><title>Methods</title><p>Forty-eight patients with gastric cancer participated in this retrospective study, and 16S rRNA sequencing was performed to evaluate formalin-fixed and paraffin-embedded (FFPE) tissue biospecimens and fresh-frozen tissues.</p></sec><sec id="sec3"><title>Results</title><p>In this study, 16 bacterial taxa at different levels, including <italic>Bacillus</italic>, <italic>Anaerococcus</italic>, and <italic>Chloroflexi</italic>, were identified to be enriched before NACT in response (R) patients in group FFPE. In contrast, 6 bacterial taxa, such as <italic>Haemophilus</italic>, <italic>Veillonellaceae</italic> (<italic>Veillonella</italic>), etc. were enriched after NACT, in which we reported for the first time that the phylum <italic>Chloroflexi</italic> was enriched before NACT in R patients. Thirty-one bacterial taxa of <italic>Coriobacteriaceae</italic>, <italic>Ruminococcaceae</italic>, <italic>Veillonellaceae</italic>, and <italic>Lachnospiraceae</italic> were identified in group mucosa as being enriched in R patients. In comparison, 4 bacterial taxa dominated by the phylum <italic>Proteobacteria</italic> were enriched in NR patients. Notably, the family <italic>Veillonellaceae</italic> was found in both tissue samples, and the metabolic pathways, including the citrate cycle (TCA cycle) and various amino acids, including alanine, were found to be potentially predictive in both sample species.</p></sec><sec id="sec4"><title>Conclusion</title><p>There are differences in the features of the GM for different NACT response results. The causal relationship deserves to be confirmed by further investigations.</p></sec>