CD4 and neoplasm: While no differences were observed in intratumoral infiltration of CD4+ or CD11b+ F4/80+ cells, a notable increase in the number of CD8+ cells and a marked decrease in Tregs were seen in Siah2−/− BM-transplanted mice inoculated with YUMMER1.7 cells, which was accompanied by increased NOS2 expression within tumor-infiltrating macrophages (Fig. 3b, c).