CD8A and hepatocellular carcinoma: As shown in Fig. 7A, T cells were categorized into four subtypes, Cd4+ T cells (Cd4+ T), Cd4+ T regulatory cells (Cd4+ Treg), Cd8+ T cells (Cd8+ T), and Cd4+Cd8+ T cells (Cd4+Cd8+ T), while B cells were divided into mature B, immature B, and high mitochondrial B cells based on the specific expression genes as described in Fig. 7B. The mitochondrial genes with crucial cell processes (such as energy supply, signal transduction, apoptosis, and metabolic pathways) are significantly increased in the liver cells of hepatocellular carcinoma patients [26].