Alteration of asparagine-linked glycosylation in serum transferrin of patients with hepatocellular carcinoma.

Abstract The asparagine-linked sugar chains in serum transferrin purified from patients with hepatocellular carcinoma ( n = 13), healthy individuals ( n = 5) and patients with liver cirrhosis ( n = 6) were compared. Sugar chains released with N -glycanase from desialylated and pepsin-digested transferrin were derivatized by reductive pyridylamination. Analysis of the sugar chains by high performance liquid chromatography in combination with exoglycosidase digestion revealed an increase of a biantennary complex-type sugar chain with a fucosylated trimannosyl core; Galβ1–4GlcNAcβ1–2Manαl-6(Galβ1–4GlcNAcβ1–2Manαl-3) Manβ1–4GlcNAcβ1–4(Fucαl-6)GlcNAc in 7 of 13 cancer patients and an increase of a sugar chain with a fucosylated trimannosyl core and bisecting N -acetylglucosamine; Galβ 1–4GlcNAc-β1–2Manαl-6(GlcNAcβ1–4) (Galβ1–4GlcNAcβ1–2Manαl-3)Manβ1–4GlcNAcβ1–4(Fuc-α 1–6)GlcNAc in one of the 13 cancer patients. Further, the fucosylated alteration of the sugar chain was detected also in α 1 -antitrypsin, hemopexin, α 1 - acid glycoprotein and α 2 -HS glycoprotein from one of the patients with increased fucosylated transferrin.