Figure 6. miR-424(322) enhances the efficacy of chemotherapy by regulating immunocyte production in ID8 tumours.

ID8 cells (5 × 10⁶) with stable overexpression of miR-424(322) were injected into the syngeneic C57BL/7 mice followed by cisplatin or vehicle (Veh) treatment. (a) Kaplan–Meier survival analysis of tumour-bearing mice in different treatment groups. t-test, **P≤0.01. (b) The number of tumours was determined in different treatment groups. t-test, *P≤0.05. Bar graphs are shown as the mean±s.e.m. (n=12 mice per group). (c–h) CD8+ T cells, Treg cells and MDSC from tumours of ID8 tumour-bearing mice were isolated and counted by FACS analysis. (c,d) Percentages of CD8+ TILs (CD45+) infiltration of total leucocytes. (e,f) Changes in percentages of CD4+ CD25+ Foxp3+ Treg in TILs. (g,h) Representative of MDSCs gated on a CD45+ cell population are shown. Cisplatin treatment significantly increased the CD8+ T-cell population and decreased the MDSC and Treg-cell population in the C57BL/7 mice with miR-424(322)-overexpressing tumours. t-test, *P≤0.05, **P≤0.01. Bar graphs are shown as the mean±s.e.m. (n=12 mice per group). (i,j) The ratios of CD8+ T cells to Treg cells or MDSC from tumour of ID8 tumour-bearing mice were determined by FACS analysis. Cisplatin treatment significantly increased the ratio of CD8+ T cells to Treg cells or MDSC in the C57BL/7 mice with miR-424(322)-overexpressing tumours. t-test, *P≤0.05. Bar graphs are shown as the mean±s.e.m. (n=12 mice per group).