Comparative study of the sugar chains of alkaline phosphatases purified from rat liver and rat AH-130 hepatoma cells.

The N-linked sugar chains of alkaline phosphatases, purified from rat AH-130 hepatoma and from normal rat liver, were released quantitatively as oligosaccharides by hydrazinolysis and were labeled by reduction with NaB ³H₄ A comparative study of their structures revealed that the following structural differences are induced by hepatocyte carcinogenesis: complex-type tetraantennary sugar chains and hybrid-type sugar chains appear; outer-chain moieties of the sugar chains of the hepatoma enzyme contain exclusively the Gal(β1-4)GIcNAc groups (type 2 chains) but those of the normal enzyme contain other Gal(Beta;1)GIcNAc groups and type 2 chains: and novel fucosylated high-mannose-type sugar chains are found in the oligosaccharides of the hepatoma enzyme. [ABSTRACT FROM AUTHOR]