Figure 5. Protein-protein interaction (PPI) network construction and gene enrichment analyses. (A) Network of E2F2 and its 50 frequently altered neighbor genes was constructed. (B) Hub genes were screened from the PPI network using the Closeness, Degree and MCC methods. (C) Functional enrichment histogram of important modules. Each biological process, cellular component and molecular function category is represented by a red, blue and green bar, respectively. The height represents the number of IDs in the user list and in the category. (D) Pathways enrichment map of E2F2 and its 50 frequently altered neighbor genes. The top 20 terms with the largest number of enriched genes were selected.