Figure 4. Anti-tumor activity of the combination of CB-839 with T cell therapy.
(A) Schedule of treatments with CB-839 and Pmel-1 cells in C57BL/6 mice (10/group). (B) B16 tumor growth in C57BL/6 mice after treatment with CB-839 or Pmel-1 cells or their combinations. Treatment time points at which CB-839 induced significant tumor growth inhibition (p<0.05) compared to vehicle are indicated by ‘+’, those of Pmel-1 compared to vehicle are indicated by ‘#’, and those of CB839+Pmel are indicated by ‘*’. (C) Kaplan Meir survival analysis of the mice with the indicated treatments. (D) Relative abundance of intermediary metabolites of the TCA cycle in tumors harvested from mice undergoing the indicated treatments. Bars represent normalized data with vehicle treatment adjusted to 1. (E) IHC analysis of tumor-intrinsic T cell numbers staining positive with either CD8 or CD4 antibodies in five random areas of 1 mm2 each. (F) IHC analysis of percentage of tumor cells staining positive for Ki67 or cleaved caspase 3 antibodies in five random areas. In E and F, significant treatment-induced differences (p<0.05) compared to vehicle are indicated by ‘#’ for the CD4+ or Ki67+ cells, and by ‘*’ for CD8+ or cleaved caspase3+ cells. (G) TILs were isolated from harvested tumors, and the percentage of IFNγ-positive CD8 T cells was determined by labeling cells with anti-Thy1.1, anti-CD8a and anti-IFNγ antibodies, followed by FACS analysis. Data is average of triplicates, and significant treatment-induced differences (p<0.05) are indicated by ‘*’.