In vivo, the miR-17-92 cluster is essential for the T cell–mediated antitumor response. (A) WT (n = 5), f/+ (n = 8), and KO (n = 7) littermates were injected subcutaneously with 2 × 105 B16/F10 melanoma cells. The tumor volume was measured each day from 7 days after injection up to 16 days and plotted against time. Left panel: the representative tumor growth curve; right panel: compiled data from 3 independent experiments. Individual dot represents the relative tumor volume normalized to that of the WT at 12 days after melanoma cell injection. (B) Lymphocytes from the dLNs of tumor-carrying mice were isolated 16 days after B16/F10 melanoma inoculation and stimulated with 1 μg/mL of anti–CD3/CD28 Abs for 24 hours. Supernatants from the cultures were assayed for the concentration of indicated Th1, Th2, and Th17 cytokines using a cytokine bead array (BD Biosciences and Bender). Each dot represents data obtained from an individual mouse (n = 3). (C) WT, f/+, and KO littermates were injected with 3 × 105 OVA-secreting B16/F0 cells. Sixteen days after injection, T cells were enriched from the dLNs, labeled with CFSE, and stimulated with LB27.4 APCs loaded with 10μM OVA peptide (323-339) for 48 hours. Antigen-specific responses (proliferation, AICD, and IFN-γ production) were measured as described above. Each data point represents the sample from an individual mouse (n = 3). Each experiment was repeated at least 3 times. *P < .05; **P < .01; and ns, no significance.
