IS THE LECTIN-BINDING PATTERN OF HUMAN BREAST AND COLON-CANCER CELLS INFLUENCED BY MODULATORS OF SIALIC-ACID METABOLISM

Sialic acid residues are the most abundant terminal carbohydrate resid ues of mammalian cells. Modification of the sialic acid residues by ex posure of cells in culture to sialic acid precursor analogues resulted in a modified susceptibility to polyoma viruses. In the present study , human breast and colon cancer cell lines were exposed for 65 h to th ese acid precursor analogues at 5 mM and their lectin binding pattern was analysed. Use of a panel of several different lectins indicated th at the pre treatment of these cell lines with the sialic acid analogue s did not change their lectin binding profile. The incorporation of th ese precursors into membrane glycoproteins was assessed by reversed ph ase high-performance liquid chromatography, which clearly demonstrated that the precursors were incorporated. The results therefore indicate that these analogues are highly specific for sialic acid and do not i nterfere with other biosynthetic pathways of membrane glycoconjugates.