In addition to the four pathways in Figure 4, KEGG pathway enrichment analysis of PPI results revealed that pathways associated with nodule formation included Pathways in cancer and Viral carcinogenesis; pathways associated with viral infection included Human T-cell leukemia virus 1 infection, Human papillomavirus infection, Epstein-Barr virus infection, Kaposi sarcoma-associated herpesvirus infection, and Human cytomegalovirus infection; pathways associated with multiple cellular processes including p53 signaling pathway were also enriched (Figure 5A). This evidence concerns the gene TP53 and human papilloma virus infection.