COMPARISON OF CARBOHYDRATE STRUCTURE BETWEEN HUMAN CHORIONIC-GONADOTROPIN PRESENT IN URINE OF PATIENTS WITH TROPHOBLASTIC DISEASES AND HEALTHY-INDIVIDUALS

  • 1 January 1985
    • journal article
    • research article
    • Vol. 76  (8) , 752-759
Abstract
Human chorionic gonadotropin (hCG) highly purified from the urine of patients with trophoblastic diseases (choriocarcinoma and hydatidiform mole) and healthy pregnant women contains 4 asparagine-linked sugar chains in 1 molecule. Comparative studies of the sugar chains released by hydrazinolysis revealed that the structures of the sugar chains of choriocarcinoma hCG are quite different from those of mole and normal hCG. The carbohydrate structures of mole hCG are the same as those of normal hCG, while all choriocarcinoma hCG examined contain 2 triantennary, 2 unusual biantennary and 1 monoantennary complex-type sugar chains which are not found in normal hCG. The triantennary and unusual biantennary sugar chains contain the .+-. NeuAs.alpha.2 .fwdarw. Gal.beta.1 .fwdarw. 4GlcNAc.beta.1 .fwdarw. 4Man.alpha.1 .fwdarw. 3 group in common. The total amounts of fucosylated sugar chains in choriocarinoma hCG are twice those found in the hCG of other groups. Therefore, the appearance of the N-acetylglucosaminyl transferase responsible for the formation of the G1cNAc.beta.1 .fwdarw. 4Man.alpha.1 .fwdarw. 3 group and the increase of the fucosyl transferase responsible for the formation of the Fuc.alpha.1 .fwdarw. 6 G1cNAc .fwdarw. Asn group appear to be specific characteristics of malignant transformation of the trophoblast, and the structural changes of sugar chains could serve as useful markers for the diagnosis of choriocarcinoma.