The microbial characteristics of esophageal squamous cell carcinoma (ESCC) and healthy subjects.

Abstract

e16546 Background: Esophageal squamous cell carcinoma (ESCC) is one of the most aggressive human malignancies. Investigation of the esophageal microbiome is a relatively new field. Recently, we discovered the microbial characteristics among the healthy subjects and patients with ESCC. Methods: DNA was extracted from blood, oral mucosa, saliva, urine, faeces samples from 28 healthy and 26 ESCC cases. Pfu high fidelity DNA polymerase was used for PCR amplification. The PCR amplification products were quantified. Then the sequencing library was prepared. The V3V4 region of the 16S ribosomal RNA gene was sequenced with Novaseq-PE250. In order to comprehensively evaluate the α diversity of microbial communities, we used Chao1 and Observed Species indices to characterize the richness, Shannon and Simpson indices to characterize the diversity. PCoA, NMDS and Distance Matrix were used to analyze differences in β diversity. Results: At the phylum level, the top 5 microbes in both ESCC and healthy samples are Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria, Fusobacteria. At the genus level, the microbial composition of patients with ESCC and healthy samples was significantly different. However, the bacteria composition in blood samples was the same as the urine samples not only in patients with ESCC but also in healthy samples. Blood and urine samples of patients with ESCC contained Cupriavidus, Vogesella, Acinetobacter, Sphingomonas, Ochrobactrum, Sediminibacterium and the healthy samples contained Ochrobactrum, Sediminibacterium, Acinetobacter. The same rule occurred in oral mucosa and saliva samples. Faeces samples of esophageal cancer patients included Streptococcus, Lactobacillus, Bifidobacterium, Gemmiger, Blautia, Coprococcus. However, the healthy samples included Gemmiger, Roseburia, Faecalibacterium, Bacteroides, Dialister, Bifidobacterium. A comparison of esophageal cancer patients and healthy samples showed that α diversity was significantly different both in blood samples and urine samples. No statistically significant differences were detected within oral mucosa, saliva, faeces samples of esophageal cancer patients and healthy samples. β diversity was different in urine samples. Conclusions: Further understanding of the changes in the esophageal microbiome may help us understand the pathogenesis and the natural history of disease and present potential therapeutic approaches.