A single-cell study of early-stage recurrent HCC found that the number of Tregs decreased in recurrent foci, dendritic cells (DC) and intratumorally infiltrating CD8+ T cells increased; T cells in recurrent tumors overexpressed KLRB1(CD161) and exhibited a naive hypocytotoxic state (Sun et al., 2021a). The gene discussed is KLRB1; the disease is hepatocellular carcinoma.