For HCC, the top 25% DEGs from the GSE62232 dataset were selected by Kong et al. to screen modules related to prognosis, and a protein-protein interaction (PPI) network was made to screened out 5 candidate genes including PCNA, RFC4, PTTG1, H2AFZ, and RRM1 [12]. The gene discussed is PTTG1; the disease is hepatocellular carcinoma.