Figure 8. Endothelial ZEB1 deletion sensitizes LLC tumors to anti–PD-1 immunotherapy.

(A) Growth curves of LLC tumors grown for 21 or 27 days in Zeb1^WT and Zeb1^iΔEC mice that were treated with 200 μg isotope control (IgG) or anti–PD-1 mAb once every 3 days for a total of 3 times (5 mice each). (B) Comparison of tumor weight of the indicated LLC tumors harvested at day 21 after implantation (5 mice each). (C) Comparison of overall survival of the indicated LLC tumor–bearing mice as described in A (5 mice each). (D and E) Representative flow cytometric plots (D) and quantification (E) of CD69⁺CD8⁺, Ki67⁺CD8⁺, CD69⁺CD4⁺, and Ki67⁺CD4⁺ T cell fractions in LLC tumors of the indicated mice as described in A (5 mice each). Tumors were harvested for flow cytometric analysis at day 18 after implantation. All data are represented as mean ± SD. *P < 0.05; **P < 0.01. Differences were tested using 2-way ANOVA with Tukey’s post hoc test (A), 1-way ANOVA with Tukey’s post hoc test (B and E), and log-rank test (C).