Whereas CD4+ T cells alone clearly have the potential to effectively eradicate tumors [66, 122, 127], the majority of published studies indicate that the optimal antitumor effects are achieved when CD4+ T cells act in concert with tumor-reactive CD8+ T cells [8, 78–80, 128–133], macrophages [6], or NK cells [7]. The gene discussed is CD4; the disease is neoplasm.