Fig. 1

Downregulation of miR-21 inhibits the immunosuppressive ability of MDSCs in lung cancer. a heat map of 19 different miRNAs of dataset GSE63805; b box line map of miR-21 of dataset GSE63805, the blue box on the left shows the expression of normal samples, and the red box on the right shows the expression of lung cancer samples (p = 2.732e−65); c, d, miR-21 expression in lung cancer cells analyzed by RT-qPCR (n = 57), * p < 0.05 vs. the normal cells; # p < 0.05 vs. the MLE-12; e the relative expression of miR-21 measured by RT-qPCR; f, g, the proportion of MDSCs, Th, CTL in the peripheral blood (f) and tumor tissues (g) of mice measured by a flow cytometer; h CD4⁺ or CD8⁺ T cells labeled with CFSC detected by flow cytometry; i, j, the inhibition effect of MDSCs on Th, CTL detected by T cell proliferation analysis; k the expression of ARG-1 and iNOS measured by RT-qPCR; l the expression of ARG-1 and iNOS protein measured by western blot analysis; m the expression of IL-10, TGF-β and GM-CSF analyzed by ELISA. * p < 0.05 vs. antagomir NC. The data in the figures were all measurements, expressed as mean ± standard deviation; n = 12. Data between two unpaired groups were compared by unpaired t-test. One-way ANOVA with Tukey’s post hoc test was used to compare data among multiple groups. The experiment was repeated three times