Alteration of N-glycan profiles in patients with chronic hepatitis and hepatocellular carcinoma

Aim: Most of the modification of N-glycosylation reported in cancers including hepatocellular carcinoma (HCC) were based on the examinations of a small number of patients or particular proteins. The aim of this study is to reveal changes in whole serum N-glycan profiles systematically during the process of hepatocarcinogenesis and to elucidate their clinical application. Methods: We analyzed sera from 105 patients with chronic hepatitis/liver cirrhosis (CH/LC) and age-/sex-matched healthy volunteers (HLT), as well as from 114 patients with HCC. Serum N-glycan profiles were measured comprehensively by a new, quantitative, high-throughput method and compared with clinical parameters. Results: The total amount of N-glycan expression was significantly higher in patients with CH/LC than in HLT; however, no differences were observed between CH/LC and HCC patients. In HCC patients, multi-antennary glycans with fucose residues, particularly m/z 3195, were increased compared with CH/LC patients. The expression of m/z 3195 was high, especially in patients with a high number of intrahepatic lesions (>3), large tumor size (>3cm), macroscopic vascular invasion or metastasis. The ratio of pairs of glycans on the same path of the biosynthesis pathway (m/z 3195/1914) showed a higher area under the receiver-operator curve of 0.810 than any other single glycan to distinguish HCC from CH/LC. Conclusion: We demonstrate the full spectrum of the alterations of serum N-glycans comprehensively in patients with liver disease, and elucidate the possible use of glycans as novel biomarkers of liver disease progression.