[Cancer-associated mucin detected by monoclonal anti-carbohydrate antibodies]

SSEA-1 antigen (stage-specific embryonic antigen-1) has been shown to be a series of carbohydrate antigens having type-2 chain and X-hapten structures. These carbohydrate antigens are remarkably accumulated in various human cancer tissues, and activity secreted into the blood stream. Frequently SSEA-1 antigens are further modified with fucoses or sialic acid in human cancer tissues, thus forming various subgroups of antigens such as fucosyl SSEA-1, sialyl SSEA-1 or polyfucosylated antigens. Many monoclonal antibodies are established which can discriminate each subgroup of antigens. Assay systems for these antigens in the sera of cancer patients have been developed using these monoclonal antibodies. Sialyl SSEA-1 is especially elevated in the sera of patients with adenocarcinoma of the lung. The antigens detected with these monoclonal antibodies are mucin-like glycoproteins(cancer-associated mucin, CAM). Various types of cancer-associated mucins can be characterized by respective monoclonal antibodies. It is therefore possible to classify cancer-associated mucins according to the structure of their carbohydrate side chains using these monoclonal antibodies.