AFP and hepatocellular carcinoma: In order to explore the heterogeneity of glycosylation in hepatocellular carcinoma (HCC) tissues with different levels of alpha-fetoprotein (AFP) in patient serum, an integrated glycoproteomics and proteomics analysis was performed on two paired groups of HCC-related tissues: ten paired tumor and paracancer tissues with low AFP concentration (< 20 ng/mL) in patients' sera, and ten paired tumor and paracancer tissues with high AFP concentration [> 1,000 ng/mL, an exclusion criterion in Milan Criteria for liver transplantation in patients with HCC (18)] (Figure 1 and Table S1).