Tumor cells are bidirectionally connected with both stromal (cancer-associated fibroblasts) and innate (tumor-associated macrophage (TAM)) cells; myeloid-derived suppressor cells (MDSCs); natural killer (NK) cells; dendritic cells; adaptive (immune cells regulatory T (Treg)) cells’ and tumor-fighting effector cells, including cytotoxic CD8 T cells and CD4 T helper cells type 1 (Th1) [181]. The gene discussed is CD4; the disease is neoplasm.