Characterization of the Esophageal Microbiota and Prediction of the Metabolic Pathways Involved in Esophageal Cancer

Donghang Li,Wenyang Jiang,Qing Geng,Guoqiang Hou,Zilong Lu,Ruyuan He,Tao Fan,Wei Ming,Haojie Feng,Lei Chen,Lin Zhang,Wei Wang

doi:10.3389/fcimb.2020.00268

Abstract

Esophageal microbiota plays important roles in esophageal cancer. Esophagectomy, as the most important therapeutic way, contributes to changes of esophageal microbiome. However, there are few studies examining the esophageal microbiome and the metabolic changes before and after esophagectomy. The present study characterized the esophageal microbiome of 17 patients with esophageal squamous cell carcinoma (ESCC), 11 patients with esophagogastric junction (EGJ) cancer, 15 patients at 9–12 months after radical esophagectomy and 16 healthy controls (HC). 16S ribosomal RNA gene sequencing was used to evaluate the microbiome and predict the metabolic pathways. Our results showed that the microbial diversity was significantly lower in ESCC, EGJ and post-ESCC groups than that in the HC group. The abundance of Fusobacteria was higher (7.01 vs. 1.12%, P = 0.039) and the abundance of Actinobacteria (1.61 vs. 4.04%) was lower in the ESCC group than that in the HC group. We found significant differences in the abundance of Bacteroidetes (20.45 vs. 9.86%, P = 0.026), Fusobacteria (7.01 vs. 1.66%, P = 0.030) between ESCC and post-ESCC groups. The results of microbial composition analysis and PICRUSt demonstrated significant differences between ESCC and HC groups. The β diversity and PICRUSt suggested that the microbial composition and metabolic pathways were similar to HC group after esophagectomy. The monitoring of the esophagus microbiota may be an essential method to predict the recurrence of tumor.

Highlights

Esophageal cancer is a rapidly growing concern worldwide, with ∼572,000 new cases annually and 509,000 deaths in 2018 (Bray et al, 2018)
Decreased Microbial Diversity and Richness in the esophageal squamous cell carcinoma (ESCC), esophagogastric junction (EGJ), and Post-ESCC Groups Compared With the healthy controls (HC) Group
Significant differences were observed in the Sobs and Shannon indexes between the ESCC and HC groups (Sobs, 324.59 vs. 565.69, P = 0.008; Shannon, 2.95 vs. 3.64, P = 0.017), the EGJ and HC groups (Sobs, 331.36 vs. 565.69, P = 0.044; Shannon, 2.48 vs. 3.64, P = 0.039), and the post-ESCC and HC groups (Sobs, 318.47 vs. 565.69, P = 0.021; Shannon, 2.48 vs. 3.64, P = 0.014, Figures 1A,B), indicating that microbial diversity was significantly lower in the ESCC, EGJ, and post-ESCC groups than that in the HC group

Summary

Introduction

Esophageal cancer is a rapidly growing concern worldwide, with ∼572,000 new cases annually and 509,000 deaths in 2018 (Bray et al, 2018). The reported risk factors of esophageal cancer included drinking, smoking, ingestion of hot food, obesity, gastroesophageal reflux disease, and Barrett’s esophagus (BE) (Bray et al, 2018; Ferlay et al, 2018). Some studies have shown lower microbial richness in the upper digestive tract to be associated with esophageal squamous dysplasia, regarded as a precursor lesion of ESCC (Yu et al, 2014). Microbiota dysbiosis, including the presence of Veillonella, Prevotella, Haemophilus, Neisseria, Campylobacter, and Fusobacterium, has been reported in association with gastroesophageal reflux disease (GRED) and is hypothesized to contribute to the evolution toward BE and adenocarcinoma at the esophagogastric junction (EGJ) (Di Pilato et al, 2016). A few studies have suggested the effect of esophageal microbiota on ESCC and EGJ, further data that can reveal the microbial composition in ESCC and EGJ are needed

Methods

Results

Conclusion