To our knowledge, HCC often exhibits distinctive intratumoral immune states, and it is reported that a combination of low intratumoral regulatory T cells (Tregs) and high intratumoral activated CD8 + cytotoxic cells (CTLs) can serve as prognostic factors of HCC, as Tregs are associated with HCC invasiveness and CTLs could help mediate anti-tumor immune response (Gao et al., 2007; Thorsson et al., 2018). The gene discussed is CD8A; the disease is hepatocellular carcinoma.