INCREASE OF FUCOSYLATED SERUM-CHOLINESTERASE IN RELATION TO HIGH-RISKGROUPS FOR HEPATOCELLULAR CARCINOMAS

Serum cholinesterase (ChE) (E.C. 3.1.1.8) is a glycoprotein which has 36 potential sites of asparagine-N-linked sugar chains. The structures of oligosaccharides released from ChE on hydrazinolysis were studied by serial lectin affinity column chromatography, exoglycosidase digest ion, and methylation analysis. Seventy-three % of the sugar chains occ urred as biantennary oligosaccharides and the remainder as C-2 and C-2 ,4/C-2,6 branched tri- and tetraantennary oligosaccharides. Several pe rcentages of the Lewis X antigenic determinant and fucosylated mannose core were linked to them, and their sialic acid residues were linked to nonreducing terminal galactose residues at the C-3 and C-6 position s.Aleuria aurantia lectin-reactive ChE with the Lewis X antigenic dete rminant increased in hepatocellular carcinomas and liver cirrhosis com pared with chronic hepatitis; on the other hand, Aleuria aurantia lect in-reactive ChE did not change significantly after transcatheter arter ial embolization and was not related to the serum levels of alpha-feto protein and carcinoembryonic antigen in patients with hepatocellular c arcinomas. Accordingly, the analysis of Aleuria aurantia lectin-reacti ve ChE is clinically useful for differentiating liver cirrhosis from c hronic hepatitis and to identify high risk groups for hepatocellular c arcinomas, i.e., cirrhotic patients in Child's A grade.