In the spleens of CT26 tumor-bearing mice, treatment had no significant effect on total CD8+ or CD4+ T cell frequencies, although anti-CTLA-4 alone or in combination with anti-PD-1 did lead to increased frequencies of Tregs as a percentage of total CD4+ T cells (p<0.05, Fig 4D). This evidence concerns the gene CTLA4 and neoplasm.