CD4 and cancer: •Perforin, TNF, TRAIL mediated cytotoxic response to cancer cells•Secretes cytokines (IFNγ, TNF-α)•Links the•Links the innate and adaptive immunity as antigen-presenting cells•Enhance antibody production through interaction with B-cells•Promote DC maturation and differentiation of naive CD4+ T cells to CTL•Improve NK cell cytotoxicity against cancer cells