CD4 and neoplasm: Tumor-antagonizing immune cells mainly consist of M1-polarized macrophages, CD8+ cytotoxic T cells, effector CD4+T cells, natural killer (NK) cells, dendritic cells (DCs), and N1-polarized neutrophils which are able to either present tumor cells, kill them directly, or secrete cytokines that interact with malignant cells [3, 4].