Fig. 4

Regnase-1 downregulation in pancreatic tumor cells increases the number of intratumoral CD11b⁺ MDSCs, accelerating tumor progression. A-D Evaluation of phenotypes of orthotopic syngeneic tumors of WT murine pancreatic cancer cells with or without coinjection of CD11b⁺ cells obtained from pancreatic tumors in pancreas-specific Kras mutant Regnase-1 knockout (PKR) mice. Representative images of HE staining and CD11b immunostaining (A, left). The number of CD11b-positive cells (A, right) (N = 6 per group) and tumor weights (B) (N = 6 per group). The relative mRNA levels of Itgam, Ly6g, Arg1, Nos2, S100a8, and S100a9 (C) (N = 6 per group). D-F Evaluation of phenotypes of orthotopic syngeneic tumors of Regnase-1-deleted murine pancreatic cancer cells with or without depletion of CD11b⁺ cells upon anti-Gr-1 antibody treatment. Representative images of HE staining and CD11b immunostaining (D, left). The number of CD11b-positive cells (D, right) (N = 6 per group) and tumor weights (E) (N = 6 per group). The relative mRNA levels of Itgam, Ly6g, Arg1, Nos2, S100a8, and S100a9 (F) (N = 6 per group). Student's t test was used to evaluate differences between 2 groups. One-way ANOVA with Tukey's post hoc test was used to compare differences among 4 groups. *P < 0.05, scale bars: 100 μm (insets)