1412P - Intestinal microbiota as a biological marker for pre-neoplastic lesion in gastric cancer in Amazonas, Brazil

Background

Introduction: In Brazil’s northern region, specifically Amazonas state, gastric cancer (GC) stands as the second leading cause of death. Stomach removal surgery remains the gold standard treatment for GC, significantly impacting the human microbiota. Certain bacteria, such as H. pylori, can modify the gastric environment, potentially leading to dysbiosis, wich may be linked to tumor progression. Therefore, this study sought to investigate whether any bacterial genus is associated with H. pylori and CG. We evaluates and correlated the intestinal microbiota profile with GC in gastrectomized patients from Amazonas/Brazil.

Methods

This observational, case-control study recruited patients with GC and a control group. Fecal samples were collected from both groups and subjected to 16S rRNA gene sequencing using next-generation sequencing platforms. Data analysis involved bioinformatics pipelines and statistical methods to identify bacterial profiles associated with GC.

Results

A total of 24 patients were included, with a mean age of 58.8±14.4 years (range: 24-81 years), predominantly male (70.8%) and diagnosed with adenocarcinoma (83.3%). Data from the intestinal microbiota revealed a notable abundance of phylum Proteobacteria at 10.4%, indicative of dysbiosis in the GC group. Among genera, Streptococcus exhibited the highest abundance (P=0.019). Comparing microbiota with cytokines levels, Alloprevotella (P=0.004) and Christensenellaceae_R-7_group (P=0.01) showed differential abundance, with reduced levels associated with multiple complications. Notably, Alloprevotella emerged as a potential biomarker for GC.

Conclusions

Our findings revealed a distinct pattern of dysbiosis among patients with GC, characterized by alterations in bacterial composition. We identified 3 bacteria with significant differential abundance in the GC group. Notably, Alloprevotella, originally an oral biofilm genus, was found in fecal material, indicating its potential of GC and its influence on intestinal dysbiosis, highlighting the importance of further research in this area.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.