a, Representative flow cytometry plots and statistical analyses of IL-4 and IFN-γ expression in CD4+FOXP3− T cells from the tumour-draining lymph nodes of 23-week-old Tgfbr2fl/fl PyMT (WT; n = 8) and Thpok-cre;Tgfbr2fl/fl PyMT (KO; n = 8) mice. Data are mean ± s.e.m. (biologically independent mice). Two-tailed unpaired t-test. b, Tumour size in Ifng−/−Tgfbr2fl/fl PyMT (Ifng−/−; n = 5), Ifng−/−Thpok-cre;Tgfbr2fl/fl PyMT (Ifng−/− KO; n = 7), Il4−/−Tgfbr2fl/fl PyMT (Il4−/−; n = 5) and Il4−/−Thpok-cre;Tgfbr2fl/fl PyMT (Il4−/− KO; n = 6) mice. Dashed lines indicate tumour burden from individual mice and solid lines indicate mean of tumour burden from all mice in a group. ****P < 0.0001.