Distribution of blood group antigens and CA 19-9 in gastric cancers and non-neoplastic gastric mucosa.
The distribution of blood group ABH antigens, their precursor I(Ma) antigen, Lewis a antigen and monoclonal antibody-defined tumor-associated antigen CA 19-9 in gastric cancers and their surrounding non-neoplastic mucosa was studied by using immunohistochemical methods. ABH antigens were localized in the foveolar epithelium except for a few cases presumed to be non-secretors, but ABH antigens were lost focally from metaplastic mucosa. In contrast, Lewis a and I(Ma) antigens were present in the foveolar epithelium of non-secretors and metaplastic mucosa where ABH antigens were not detected. Gastric cancers also showed focal loss of ABH antigens and gain of Lewis a and I(Ma) antigens, and the cancer cells showed marked heterogeneity in antigen expression compared with non-neoplastic mucosa. Expression of incompatible blood group antigen (A-like antigen) reactive with monoclonal anti-A antibody was also detected in cancer cells of blood group O and B cases. CA 19-9 (sialylated-Lewis a) was detected in 62% of gastric cancers and in the restricted areas of gastric mucosa where Lewis a was positive.
D000017:ABO Blood-Group System; D000951:Antigens, Neoplasm / Q000032:analysis*; D005753:Gastric Mucosa / Q000276:immunology; D006801:Humans; D007983:Lewis Blood Group Antigens; D008679:Metaplasia / Q000276:immunology; D013270:Stomach / Q000276:immunology* / Q000473:pathology; D013274:Stomach Neoplasms / Q000276:immunology*
D000017:ABO Blood-Group System; D000951:Antigens, Neoplasm; D007983:Lewis Blood Group Antigens