As the primary component of antitumor immunity, tumor antigen‐specific cytotoxic T (CTL) execute their tumor‐killing activity through multiple means, including the secretion of effector cytokines such as IFN‐γ or soluble factors (perforin and granzyme B) to disturb targeted cell proliferation and induce tumor cell lysis [12]. The gene discussed is PRF1; the disease is neoplasm.