Carbohydrate antigens in human cancer.

Studies with naturally occurring and hybridoma-derived monoclonal antibodies have shown that surface and secreted antigens which distinguish human tumour cells from their normal counterparts are predominantly carbohydrate structures. Many of these belong to a family which includes the major blood-group antigens. In fact, the blood-group genes and the related secretor gene account for the individual and tissue-specific patterns of expression of several carbohydrate antigens as normal or as tumour-associated antigens. The biochemical basis of the tumour-associated changes requires investigation. In particular, it will be important to determine whether they are the result of aberrant expression of the glycosyltransferase genes. Their contribution to the disordered growth regulation in tumour cells will also be important to assess, particularly as the blood group family of oligosaccharides are among major antigenic components of the receptor for epidermal growth factor. Monoclonal antibodies to carbohydrate structures have opened new avenues of research into the biochemistry of tumour cells.