Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed the functions of genes in cluster 4, 5, and 7 were enriched in several cancer‐related pathways, such as cytokine–cytokine receptor interaction, chemokine signaling pathway, Toll‐like receptor signaling pathway, tumor necrosis factor (TNF) signaling pathway and hepatitis C (Figure 3C). This evidence concerns the gene TNF and hepatitis A virus infection.