FIG 1.

Oral cancer bacterial communities differ with the clinical stage of cancer. Bacterial alpha diversity indices among different stages of oral cancer were measured by Chao1 index (A) and Shannon diversity index (B). Bacterial beta diversity indices between precancer and cancer groups were measured by weighted UniFrac distance (C) and unweighted UniFrac distance (D). Statistical analysis was done by one way ANOVA followed by the Kruskal-Wallis test. *, P < 0.05; **, P < 0.01; ***, P < 0.001.