Fig. 3: Causal impact of the gut microbiota on prostate cancer.

a Total DNA was extracted from feces of C57BL/6 N mice at baseline, after 1 week of antibiotic (Abx) treatment and after series of two fecal microbiota transplants (FMT). Microbiota depletion was performed by Abx treatment and mice were rescued with their pre-Abx fecal microbiota transplant (mFMT, n = 4 mice) or transplanted with fecal samples from six independent patients with grade group ≥2 localized prostate cancer (n = 4 mice/group for hFMT1, 2, 4, 5, 6 and n = 8 mice for hFMT3). The hFMT3 was repeated twice in two different experiments. b Gifu Anaerobic Media (GAM) broth cultures of fecal samples from mice before (baseline) and after 4 days of Abx treatments (Abx, n = 16), controls were mice untreated (n = 4). c C57BL/6 N Abx-pretreated mice received two FMT from 6 independent patients with localized prostate tumor. After the FMTs, mice were injected with TRAMP-C2 prostate tumour cells and tumour mass was measured at sacrifice, 5 weeks after tumour cells injections (n = 4 mice/group for hFMT1, 4, 5, 6, n = 3 mice for hFMT2 and n = 8 mice for hFMT3). p = 0.006 (hFMT2), p = 0.007 (hFMT3), p = 0.04 (hFMT4) and p = 0.01 (hFMT5), Student’s t-test. d The data in (c) was compiled based on the donor’s tumor volume at the pathological analysis and corresponding to the tertiles defined in Fig. 1a (n = 4 mice for mFMT, n = 7 low tumour volume hFMTs, n = 8 medium tumour volume hFMTs and n = 12 High tumour volume hFMTs), p = 0.04 (Low), p = 0.007 (Medium) and p = 0.04 (High), Student’s t-test. e GAM broth cultures of fecal samples from mice before corresponding to (d) (n = 4 mice for mFMT, n = 7 low tumour volume hFMTs, n = 8 medium tumour volume hFMTs and n = 12 High tumour volume hFMTs), p = 0.03, two-sided Welch’s t-test. Graphs are mean ± SEM.