PTEN and neoplasm: In addition, the microbiota from animals with Pten−/−; Rb1−/− tumours were significatively different from the microbiota of no tumour controls using the Bray-Curtis beta-diversity principal component analysis (Fig. 2h, p = 0.02, Permanova), similar to the same analysis in the TRAMP-C2 model (Fig. 2d).