TH2-polarized CD4+ T cells secrete cytokines that can limit CTL differentiation and proliferation such as IL-10 and IL-4, while CD4+ TRegs (FOXP3+) have significant immunosuppressive functions through various mechanisms and their pro-tumor role has been described in both solid tumors and lymphomas (13, 27–29). The gene discussed is CD4; the disease is lymphoma.