ARG1 and neoplasm: To further solid the possibility of these hub genes as the potential biomarker of HBV-positive HCC, we compared the protein expression level of 12 candidate DEGs from of HBV-positive HCC patients on public National Omics Data Encyclopedia (NODE) database (OEP000321), and showed ALDH8A1, ALDOB, ARG1, ANGPTL6, PALM2 and TAT were significantly downregulated in HBV-positive HCC tumor tissues compare with corresponding adjacent non-tumor tissues (Fig. 7A).