TCF1 overexpression in CD8+ tumor-infiltrating lymphocytes (TILs) enhanced cytokine-producing capacity and suppressed co-inhibitory receptor expression while retaining a heightened response to checkpoint blockade, leading to enhanced tumor control (Kurtulus et al., 2019; Siddiqui et al., 2019; Shan et al., 2020). The gene discussed is CD8A; the disease is neoplasm.