COL8A1 and hepatocellular carcinoma: Regarding the 1779 overlapping upregulated DEGs and CEGs positively related to COL8A1, the following KEGG pathways were significantly aggregated (Fig. 6a): proteoglycans in cancer (Additional file 17: Figure S13), ECM-receptor interaction (Additional file 18: Figure S14), and several cancer pathways (such as thyroid cancer, colorectal cancer, and hepatocellular carcinoma).