Fig. 3: Anti-PD-1 therapy improved hypoxia and promoted vessel normalization.

a Treatment schema. b Tumor tissues of 4T1 breast cancer mouse model removed at day 11. c Representative images and quantification of tumor hypoxia with HIF-1α and Pimonidazole (Scale bars, 50 μm). d Analyses of tumor weight in (b) (n = 6 mice per group). e, f Analyses of tumor hypoxia in (c) (n = 6 mice per group). g, h Immunofluorescence quantification of percentage endothelial cells (CD31⁺) attached by pericytes (NG2⁺) (n = 4 to 5 mice per group). Data were representative of two independent experiments and presented as means ± SD. P values were calculated using two-tailed unpaired Student’s t-test (d–g).