CD4 and neoplasm: The origin of these inflammatory mediators varies within the tumor and may arise from various cell types, including polarized “M2-like” (Arg1high/CD206high/IL-10high) pro-tumoral macrophages (tumor-associated macrophages; TAMs) [128], myeloid-derived suppressor cells (MDSCs) [129], CD4+Foxp3+ regulatory T cells (Tregs) [130], and/or the tumor cells themselves [112].