Fig. 3

Inhibition of lung tumorigenesis in miR-301a^−/−Kras^LA2 mice correlates with elevated IFN-γ expression. (a) Cytokine gene expression were measured by qPCR in lung tumors isolated from Kras^LA2 (n = 5) and miR-301a^−/−Kras^LA2 (n = 5) mice at 9 weeks of age. (b) Relative expression IFN-γ in tumor tissues of WT (n = 3), miR-301a^−/−(n = 3), Kras^LA2 (n = 5), and miR-301a^−/−Kras^LA2 (n = 5) mice at 9 weeks of age were validated and determined by qPCR. (c) Single-cell suspensions were isolated from lung tissues (n = 5 per group), and IFN-γ secretion ex vivo was determined by ELISA. (d) Representative results of IFN-γ expression by CD3⁺ T cells isolated from lung tumors in 9-week-old Kras^LA2 (n = 5) and miR-301a^−/−Kras^LA2 mice (n = 8). (e) The percentage of IFN-γ-positive and CD3-positive cells was counted using flow cytometric analysis of lung tissues from Kras^LA2 (n = 5) and miR-301a^−/−Kras^LA2 (n = 8) mice at 9 weeks of age. (f) Relative expression levels of IFN-γ for CD3⁺, CD4⁺ and CD8⁺ T cells of lung tissues from WT (n = 5) and miR-301a^−/− mice (n = 5). Values represented the mean ± s.d. of three independent experiments. **P < 0.01 or *P < 0.05 indicates a significant difference between the indicated groups (two-tailed, unpaired Student’s t-test in a, e and f and one-way analysis of variance (ANOVA) in b and c). NS, not significant