Organ-specific mucin antigens and gastrointestinal carcinogenesis

Organ-specific mucin antigens detected by polyclonal antibodies were first used to characterize abnormal differentiation of gastrointestinal (GI) adenocarcinomas (1,2). These mucin tumour markers can thus be useful as criteria for evaluating the degree of gastric or intestinal differentiation of gastric carcinomas. In addition, some of these mucin antigens are expressed early during GI carcinogenesis where they are associated to premorphological abnormalities (3-5). Consequently, these markers are of importance for studying genetic changes occurring in precancerous mucosa, in which cancer cell transformation can occur. Finally, recent observations have pointed out a putative value of these mucin antigens for screening high risk populations for GI cancers. First of all, we shall define the words: mucin, mucin antigen (or epitopes) and organ-specificity before described abnormal antigen expression during GI carcinogenesis in the cancerous and in the precancerous mucosae and specially concerning their association with premorphological abnormalities.