Characteristics of Oral Microbiota in Patients with Esophageal Cancer in China

Gut microbiota dysbiosis is closely associated with intestinal carcinogenesis, but the oral microbiota of patients with esophageal squamous cell carcinoma who live in high-risk regions in China has not been fully characterized. In the current study, oral microbial diversity was investigated in 33 patients with esophageal squamous cell carcinoma and 35 healthy controls in Chongqing, China, by sequencing 16S rRNA of V3-V4 gene regions. There were statistically significant differences in oral microbiota between esophageal squamous cell carcinoma patients and controls as determined via unweighted pair-group analysis with arithmetic means. At the phylum level, in esophageal squamous cell carcinoma patients, there were comparatively greater amounts of <i>Firmicutes</i> (34.0% vs. 31.1%) and <i>Bacteroidetes</i> (25.3% vs. 24.9%) and lower amounts of <i>Proteobacteria</i> (17.0% vs. 20.1%). At the genus level, esophageal squamous cell carcinoma patients exhibited comparatively greater amounts of <i>Streptococcus</i> (17.3% vs. 14.5%) and <i>Prevotella_7</i> (8.6% vs. 8.5%) and lower amounts of <i>Neisseria</i> (8.1% vs. 10.7%). Using a linear discriminant analysis effect size method, <i>Planctomycetes</i> and <i>Verrucomicrobia</i> were identified in the esophageal squamous cell carcinoma group. 10 genera were higher abundances identified in the healthy control group, and different 10 genera were identified in the esophageal squamous cell carcinoma group. In the present study, there were significant differences in oral microbial compositions of esophageal squamous cell carcinoma patients and healthy controls. Further longitudinal and mechanistic studies are needed to further characterize relationships between oral microbiota and esophageal squamous cell carcinoma.