Fig. 2

Detection and validation of real recurrence-related hub genes of iCCA. a GO enrichment analysis of the red module: all terms were analyzed (P < 0.05). b KEGG pathway enrichment analysis of the red module: the top 10 pathways were shown. c Scatterplot of module eigengenes in the red module. The red dots represent genes with MM > 0.8 and GS > 0.2, which composed the Red_Hub gene list. d The 40 key genes in the PPI network detected by the cytoHubba algorithm, which formed the PPI_Hub gene list. The rank of genes was indicated by color (the redder the color is, the more important the gene is), and the number of edges was indicated by the diameter of the circle (the greater the number of edges is, the larger the diameter is). e Detection of candidate hub genes: 11 genes (ESR1, A2M, TEK, KDR, S1PR1, HGF, RAPGEF4, STAB2, EPAS1, TAB2 and VDR) were selected as candidate hub genes. f Detection of real hub genes: three methods including qRT-PCR, IHC and DFS analysis were used to determine the real hub genes. ESR1 was selected to be the real hub gene