CD8A and neoplasm: Moreover, the Hepa1-6 KO tumor tissues exhibited mild intratumoral infiltration of CD8+ T cells and marked enrichment of forkhead box protein 3 (Foxp-3)+ Treg cells compared to the Hepa1-6 NC tumor tissues in the syngeneic subcutaneous transplantation model (Figure 3F), indicating the downregulation of the CD8/Foxp-3 ratio (Figure 3G).