title: Cell shape modulation alters glycosylation of a metastatic melanoma cell-surface antigen.
abstract: B16-F1 melanoma cells cultivated in vitro as spheroids on a non-adhesive substrate acquire in a reversible fashion an increase in lung colonization in vivo as compared to cells cultured as a monolayer. After neuraminidase treatment of protein blots, the spheroidal cells expressed an increased binding of 125I-labelled peanut lectin (PNA) to a unique glycoprotein of Mr 78,000 (gp78) which after desialylation migrated in SDS-polyacrylamide gels as an Mr 86,000 protein. Antibodies were generated against this glycoprotein purified on PNA-Sepharose and its expression on the surface of viable B16-F1 cells was demonstrated. Growth of B16-F1 melanoma cells in suspension is associated with the altered glycosylation of gp78 which may be related to the increased metastatic ability of these cells. In vitro treatment of B16-F1 cells with anti-gp78 Fab fragments prior to their injection into the tail veins of syngeneic mice resulted in a 2-fold increase in the appearance of tumor lung colonies.
mesh_terms: D000818:Animals; D000912:Antibodies, Neoplasm / Q000276:immunology; D000951:Antigens, Neoplasm; D005260:Female; D006023:Glycoproteins / Q000032:analysis* / Q000276:immunology; D006031:Glycosylation; D037102:Lectins / Q000378:metabolism; D008175:Lung Neoplasms / Q000556:secondary; D008546:Melanoma, Experimental / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D058950:Melanoma-Specific Antigens; D051379:Mice; D008810:Mice, Inbred C57BL; D008970:Molecular Weight; D009363:Neoplasm Proteins / Q000378:metabolism*; D009844:Oligosaccharides / Q000502:physiology; D019887:Peanut Agglutinin
chemical_list: D000912:Antibodies, Neoplasm; D000951:Antigens, Neoplasm; D006023:Glycoproteins; D037102:Lectins; D058950:Melanoma-Specific Antigens; D009363:Neoplasm Proteins; D009844:Oligosaccharides; D019887:Peanut Agglutinin