title: Bromodeoxyuridine-induced molecular species conversion of sialic acids of gangliosides and the alteration of cellular phenotypic expression in B16 mouse melanoma cells.
abstract: Gangliosides of B16 mouse melanoma cells were characterized and the effects of 5-bromodeoxyuridine (BrdU) on gangliosides were examined in relation to the alteration of cellular phenotypic expression. In melanotic cells, gangliosides were shown to be composed of both hematosides containing N-acetylneuraminic acid (NeuAc-hematoside) and N-glycolylneuraminic acid (NeuGc-hematoside) as determined by thin-layer chromatography, gas chromatography-mass spectrometry and the use of anti-NeuGc-hematoside antiserum. Gangliosides other than hematosides were not detectable under the conditions of thin-layer chromatography employed. BrdU treatment of the melanotic cells induced about a two-fold increase in the ratio of NeuGc-hematosides to the total hematosides without any significant change in the cellular ganglioside content. The treatment concomitantly induced a change in cellular morphology, an increase in cell-to-substrate adhesiveness, and the suppression of tyrosinase activity. Amelanotic cells, which showed cellular phenotypes similar to those of BrdU-treated melanotic cells, were demonstrated to have over twice as much NeuGc-hematosides as compared with the melanotic cells. These results indicate a possible relationship in melanoma cells between the molecular species conversion of sialic acids of hematosides and the alteration of cellular phenotypic expression by BrdU treatment or spontaneous amelanization.
mesh_terms: D000818:Animals; D001973:Bromodeoxyuridine / Q000494:pharmacology*; D002448:Cell Adhesion; D002478:Cells, Cultured; D005732:Gangliosides / Q000378:metabolism*; D008545:Melanoma / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D014442:Monophenol Monooxygenase / Q000378:metabolism; D009363:Neoplasm Proteins / Q000378:metabolism; D009374:Neoplasms, Experimental / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D012794:Sialic Acids / Q000378:metabolism*
chemical_list: D005732:Gangliosides; D009363:Neoplasm Proteins; D012794:Sialic Acids; D014442:Monophenol Monooxygenase; D001973:Bromodeoxyuridine