DBF4 and hepatocellular carcinoma: In order to further explore the possible correlated signal pathways through which DDK complex functions in the development of HCC, we firstly screened the genes that positively or negatively correlated with DBF4 or CDC7 in TCGA HCC data by pearson correlation analysis (Table S1 and S2), and then GSEA was performed on Linkedomics online website (http://www.linkedomics.org/) to identify the signaling pathways these genes belong to (Fig. 5A-D).