This project will investigate the role of sialic acid composition of cellular glycoproteins in mediating the effects of oncogenic transformation and investigate the mechanisms by which other transformation-associated biochemical alterations affect sialoglycoproteins. Two basic approaches to investigating this problem are being taken: 1) the selection and characterization of variant normal and transformed cell lines with altered sialoglycoprotein composition, and 2) the analysis of the effects of oncogenic transformation and a variety of cell growth conditions on the structure of an individual sialic acid-containing oligosaccharide system.