[Glycoproteins associated with metastatic potential of cancer].

Carbohydrate moieties of glycoproteins have been implicated to be involved in cellular adhesion. Therefore, certain carbohydrate structures in glycoproteins are expected to be associated with metastatic behaviour of cancer cells; such carbohydrate structure can be used as an indicator for the treatment of cancer patients based on the predicted metastatic potential of the cancer cells. The following results recently reported is interesting from the above view point. In certain cancer cells of the mouse, beta 1----6 branching of asparagine-linked oligosaccharides, which can be detected by the reactivity with PHA-L lectin, associates with increased metastatic potential. In human bladder carcinomas, reactivity with Lotus tetragonolobus agglutinin (LTA) correlates with increased metastatic potential. LTA appears to react with Lex structure [Gal beta 1----4(Fuc alpha 1----3)GlcNAc] in the cancer cells. Expression of sialilated dimeric Lex increases in the metastatic nests of human colon carcinomas. On the other hand, sialyl antigen MGl has the tendency to be expressed in human gastric adenocarcinoma of low metastatic potential. MGl is defined by a monoclonal antibody raised against Ricinus communis agglutinin receptors isolated from human gastric adenocarcinoma xenografted in nude mice. Continued efforts using monoclonal antibodies and lectins may yield arrays of carbohydrate markers of clinical value to predict the metastatic potential.