TOP2A and hepatocellular carcinoma: Based on the results that the expression status of CDCA8, KPNA2, PRC1 and TOP2A were correlated with the OS for HCC patients (Fig. S4), we further performed the multivariate Cox regression analysis to construct a 4-DEmRNA signature for predicting the prognosis of HCC patients in TCGA project and validated the prognostic value of 4-DEmRNA signature in ICGC project.