Fig. 2

Comparisons of microbial diversity. A, C, and E: the boxplot of alpha diversity between the EIESC and controls using the Chao1 (A), Shannon(C), and Simpson index (E). B, D and F: the Rarefaction curves of the diversity detected compared with the predicted diversity. The x-axis represents the number of sequences sampled while the y-axis represents the estimated Chao1 (B), Shannon index (D), and Simpson index (F). G: PCoAs of Bray‒Curtis distances on the microbiota distributions. Each dot represents a patient with EIESC or controls. Points clustered in red and blue represent the gastric microbial composition of the EIESC and controls, whereas the points clustered in yellow, blue represent the oral microbial composition of the EIESC and controls. EIESC: early-stage intramucosal esophageal squamous cell carcinoma; PCoAs: principal coordinate analyses. H: UpSet plot of differently-distributed taxa. The left graph represents the total number of differently-distributed species (X-axis) in EEC saliva (EEC_o), Control saliva (NC_o), EEC gastric biopsy (EEC_g), and control gastric biopsy groups (EEC_g) (Y-axis). The right graph represents the intersection of sets of species in multiple groups. Each column corresponds to a group or set of groups (dots connected by lines below the X-axis) containing the same species. The number of species in each set appears above the column, while groups shared are indicated in the graphic below the column. *, **, *** stands for p-value < 0.01, 0.005 and 0.001, respectively). EEC: early esophageal cancer