Accumulation of gangliosides with N-acetylneuraminosyl(alpha 2-6)lactosamine structure in primary human hepatoma.
Gangliosides of hepatomas have been analyzed by using a monoclonal antibody directed to N-acetylneuraminosyl(alpha 2-6)lactoneotetraosylceramide (sialyl(alpha 2-6)paragloboside), which was prepared by injecting the monosialoganglioside fraction of human meconium into BALB/c mice. The monoclonal antibody, named MSG-15, was found to bind sialyl(alpha 2-6)paragloboside, but it failed to react with other gangliosides, including N-acetylneuraminosyl(alpha 2-3)lactoneotetraosylceramide (sialyl (alpha 2-3)paragloboside) and "Ii"-type gangliosides. MSG-15 was found to recognize NeuAc alpha 2-6Gal beta structure of the ganglioside. Gangliosides obtained from human hepatomas were analyzed by immunostaining on high-performance thin-layer chromatography plates using the monoclonal antibody MSG-15. All primary hepatoma samples used in this study (nine samples) were found to contain sialyl(alpha 2-6)paragloboside, which accounted for 13-31% of the monosialoganglioside fractions in the hepatomas. Furthermore, MSG-15 recognized several monosialogangliosides in addition to sialyl(alpha 2-6)paragloboside. These gangliosides apparently also contain a terminal NeuAc alpha 2-6Gal beta structure. Other ganglioside fractions obtained from hepatoma and meconium were immunostained on thin layer chromatography plates with MSG-15. Additionally, another monoclonal antibody (H-11), which recognizes terminal lactosamine structure, was used to immunostain these fractions after sialidase treatment. Bands stained with both monoclonal antibodies showed similar mobilities to each other in the di- and trisialoganglioside fractions as well as monosialoganglioside fraction. In control liver, GM3 ganglioside accounted for 92% of monosialoganglioside fraction, and sialyl(alpha 2-6)paragloboside accounted for less than 1% of the fraction. Immunohistochemical study by using MSG-15 in tissue sections from hepatocellular carcinoma and normal liver tissues demonstrated that only hepatocellular carcinoma cells gave a positive reaction. These results suggest that the biosynthetic pathway of gangliosides containing NeuAc alpha 2-6Gal beta 1-4GlcNAc beta structure is activated in hepatoma cells.
Taki
T
T
Department of Biochemistry, School of Pharmaceutical Science, University of Shizuoka, Japan.
Yamamoto
K
K
Takamatsu
M
M
Ishii
K
K
Myoga
A
A
Sekiguchi
K
K
Ikeda
I
I
Kurata
K
K
Nakayama
J
J
Handa
S
S
D000818:Animals; D000911:Antibodies, Monoclonal; D006528:Carcinoma, Hepatocellular / Q000032:analysis*; D055598:Chemical Phenomena; D002621:Chemistry; D005679:G(M3) Ganglioside / Q000032:analysis*; D005732:Gangliosides / Q000032:analysis*; D005915:Globosides / Q000032:analysis*; D006028:Glycosphingolipids / Q000032:analysis*; D006801:Humans; D008113:Liver Neoplasms / Q000032:analysis*; D051379:Mice; D008807:Mice, Inbred BALB C; D009844:Oligosaccharides / Q000032:analysis*
D000911:Antibodies, Monoclonal; D005679:G(M3) Ganglioside; D005732:Gangliosides; D005915:Globosides; D006028:Glycosphingolipids; D009844:Oligosaccharides; C025447:sialogangliosides; C062923:N-acetylneuraminosyl(alpha2-6)lactosamine; C014812:sialosylparagloboside