While generally cytotoxic, Tc1 cells produce cytokines such as interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and granzyme B, which may exert immunomodulatory effects and, under certain conditions, support tumor progression through mechanisms that resemble those of CD4+ helper T cells [44]. The gene discussed is CD4; the disease is neoplasm.