Fig. 6. Mi-2β inhibitor Z36-MP5 induced immune response to immunotherapy in resistant melanoma.

a Mice bearing B16F10 cell graft were treated with control IgG or anti-PD-1 antibodies, and vehicle control or Z36-MP5, as indicated, and the growth of tumor grafts was shown. For each group n = 5. Mice bearing B16F10 cells were treated with control IgG or anti-PD-1 antibody, and vehicle control or Z36-MP5, as indicated. For each group n = 5. Tumor weight (b) and mouse survival curve (c) were shown, with log-rank test for mouse survival curve P value. d, e Tumor-infiltrating lymphocytes (TILs)were assayed and quantified for CD4⁺ and CD8⁺ T-cell number in total CD45⁺ cells by flow cytometry (n = 5). f Granzyme B expression in CD8⁺ T was determined and quantified by flow cytometry (n = 5). g Mice carrying conditional alleles of Tyr::CreER;BRaf^CA;Pten^lox/lox were administered with tamoxifen for 5 days to activate CreER to cause melanocyte-specific conversion of Braf^CA to Braf^V600E, and the conversion of the Pten^lox/lox alleles to null alleles, which express proteins of BRaf^V600E/Pten^nul. Mice with measurable tumors were randomly treated with either control IgG (10 mg/kg) or anti-PD-1 antibodies (10 mg/kg) and Z36-MP5 (30 mg/kg/day) as indicated. For each group n = 10. Mouse survival was shown with log-rank test for P value. h TILs were assayed by flow cytometry. The number of CD8⁺ T cells gated within CD45⁺ T cells were demonstrated (n = 5). i The expression of Granzyme B in CD8⁺ T was determined and quantified by flow cytometry (n = 5). MFI, mean fluorescence intensity. j A schematic for experimental strategy with anti-CD8 antibodies and Z36-MP5 treatment on melanoma mouse model. k, l Mice bearing B16F10 cell graft were treated with control IgG, anti-CD4 or anti-CD8, and then treated with Z36-MP5. The tumor volum (k) and weight (l) were shown. For each group n = 5. a, b, e, f, h, i, k, l Values represent mean ± SD. The unpaired, two tailed t-test. Source data are provided as a Source Data file.