The role of different components (including tumor-associated macrophages (TAM), myeloid-derived suppressor cells (MDSC), regulatory T cells (Tregs), CD8+ cytotoxic T lymphocytes, fibroblasts) of tumor microenvironment (TME) in hepatocellular carcinoma has also been discussed in many studies [16]. The gene discussed is CD8A; the disease is hepatocellular carcinoma.