Characterization of glycosylation and adherent properties of melanoma cell lines.

The repertoire of oligosaccharide components of cellular glycoproteins significantly contributes to cell adhesion and communication. In tumor cells, alteration in cellular glycosylation may play a key role in giving rise to invasive and metastatic potential. Over 100 melanoma cell lines deposited in the ESTDAB Melanoma Cell Bank (Tubingen, Germany) were studied for the characteristic glycan composition related to tumor progression. Analysis of: (1) cell adhesion to extracellular matrix proteins--fibronectin, laminin, and collagen; (2) the expression of selected glycosyltransferases--alpha2,3(Gal beta1,3)- and alpha2,3(Gal beta1,4)-sialyltransferases, alpha1,2- and alpha1,3-fucosyltransferases, and N-acetylglucosaminyltransferase V; (3) characterization of N-glycans was carried out on uveal (4), primary cutaneous (6), and metastatic (96) melanoma cell lines. Results showed that uveal cells did not adhere to any of the substrates and, in general, possessed less glycans containing alpha-2,6- and alpha-2,3-linked sialic acid. The average number of polypeptides bearing beta-1,6-branched tri- and tetra antennary glycans (characteristic of the metastatic phenotype) were similar in uveal, primary cutaneous, and metastatic melanoma cell lines. Characterization of N-glycans may open a new perspective in the search for specific glycoproteins that could become targets for the therapeutic modulation of melanoma.