Despite not seeing an increase in T cell frequency by flow cytometry (Supplementary Figure 5B) nor any difference in CD8+ effector T cell to Treg ratio (Supplementary Figure 5I), immunohistochemistry analysis of tumor sections did reveal a significant increase in CD8+ T cells in MC38 tumors from Ptpn6fl/flERT2-cre mice relative to controls. This evidence concerns the gene CD8A and neoplasm.