Moreover, while the numbers of the CD4+cell subset remained unchanged in the peritumoral areas surrounding the tumor foci, CD4+ T cell counts increased within the tumor foci (intra-tumoral) developed in the liver collected from mice inoculated with C26 cells but not in those tumors observed within the livers of mice bearing β2-C26 cells (Fig. 9b and Additional file 4). This evidence concerns the gene CD4 and neoplasm.