Fig. 1. Arf1 knockdown reduces the CSC and extends the lifespan of Lgr5/Apc mice.

a LacZ-stained sections of intestine from an Axin2-CreER/Rosa26R or an Axin2-CreER/Rosa26R/Arf1^f/f mouse that was treated with five intraperitoneal injections of tamoxifen to activate stem-cell-specific Cre and facilitate the loss of Arf1. b Lgr5/Apc or Lgr5/Apc/Arf1 mice were treated with three continued intraperitoneal injection of tamoxifen to activate the stem-cell-specific Cre and facilitate the loss of Apc and Arf1. β-Catenin and GFP mark stem cells. c Intestinal tumor number in the indicated genotypes (n = 15 mice per group; ***p < 0.001, t-test; repeated three independent times). d Percent survival curves of mice with the indicated genotypes (n = 15 mice per group; ***p < 0.001, t-test; repeated three independent times). e, f Electron microscopy sections of mouse intestinal crypts with the indicated genotypes. g Immunofluorescent staining of CD3, GFP, and Hoechst in intestinal sections of mice with the indicated genotypes. h Quantification of infiltrated CD3⁺ T cells in mice with the indicated genotypes (n = 15 mice per group; n.s. is not significant, **p < 0.01, ***p < 0.001, t-test; repeated three independent times). Each experiment replicate three times. Data are shown as the mean ± SEM. Scale bars are as indicated.