Fig. 2. Fungal dysbiosis enhances the tumor response to radiation.

Orthotopic E0771 mammary tumors (A-D) were treated with antifungals (AF) for one week prior to being treated with localized kV irradiation (16 Gy). Both individual tumors (A, B), mean tumor burden ± SEM (C) and survival (D) were treated with their indicated treatments and assessed every 3 days until endpoint. The antifungal (AF) was fluconazole with similar results observed using 5-fluorocytosine (Supplemental Figure S2). Subcutaneous B16 melanomas (E, F) were treated with antifungals (AF) for one week prior to being treated with localized kV irradiation (16 Gy). Total tumor burden/animal was assessed every 3 days until endpoint. Mean tumor burden ± SEM (E) and survival (F) with the indicated treatments is shown. DNA from fecal pellets obtained from AF treated mice were examined by quantitative PCR for bacterial 16S and fungal 18S ribosomal DNA and the fold change from untreated mice with standard error was calculated (G). E0771 tumors from mice were harvested at one week following RT and stained for bromodeoxyuridine (BrdU) and cleaved caspase 3 (CC3) to quantitate the number of BrdU (H) and CC3 (I) positive cells to assess for proliferation and cell death respectively. Significance was determined by two-way ANOVA with post-hoc testing for tumor growth, Log-Rank test for the Kaplan-Meier survival curves and Student’s t-test with Welch’s correction for the IHC. Numbers (n) for each experiment are listed on the figure and are pooled data from at least two independent experiments. For all figures, significance is shown as *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.