title: Simple mucin-type carbohydrate antigens (Tn, sialosyl-Tn and T) in gastric mucosa, carcinomas and metastases.
abstract: Immunohistochemical study of the expression of simple mucin-type carbohydrate antigens (Tn, sialosyl-Tn, T and sialosyl-T) was performed using specific monoclonal antibodies in the mucosa adjacent to gastric carcinomas histologically appearing unaffected (n = 58), and in primary gastric carcinomas (n = 87) and their metastases (329 lymph nodes and two liver metastases). Normal-looking mucosas: Tn antigen expression was identified in all the cases; sialosyl-Tn in eight cases; T antigen was never expressed and sialosyl-T antigen was observed in four cases; the expression of these antigens was distinctly limited to the cytoplasm, mostly in the supranuclear (Golgi) area. All the mucosas with intestinal metaplasia showed sialosyl-Tn expression in the goblet cells. Gastric carcinomas: 80 cases (91.9%) stained for Tn antigen, 69 cases (19.3%) expressed sialosyl-Tn antigen, 18 cases (20.7%) expressed T antigen and 17 cases (19.5%) stained for sialosyl-T antigen. In contrast to normal mucosa, carcinoma cells expressed simple mucin-type antigens both at the cytoplasm and at the cell membrane. Most primary carcinomas were concurrently stained for Tn and sialosyl-Tn antigens alone (41.1%), or together with T antigen or sialosyl-T antigen (28.7%). We found a close relationship between the expression of simple mucin-type carbohydrate antigens in the primary tumours and their respective metastases. T antigen (and sialosyl-T antigen) expression was correlated with the wall invasiveness of the tumours. The 18 tumours expressing T antigen and 16 out of the 17 tumours expressing sialosyl-T antigen had nodal metastases and/or sialosyl-Tn expression and the aggressiveness of the tumours (wall penetration, lymph node metastasis and venous invasion). No significant differences were observed between positive and negative tumours for Tn, sialosyl-Tn, T and sialosyl-T antigens regarding the morphologic at type, growth pattern, ploidy or lymphoid infiltrate of the primary tumours.
authors.affiliation: Department of Pathology, Medical School, University of Porto, Portugal.
authors.forename: L
authors.initials: L
authors.lastname: David
authors.forename: J M
authors.initials: JM
authors.lastname: Nesland
authors.forename: H
authors.initials: H
authors.lastname: Clausen
authors.forename: F
authors.initials: F
authors.lastname: Carneiro
authors.forename: M
authors.initials: M
authors.lastname: Sobrinho-Simões
mesh_terms: D000911:Antibodies, Monoclonal; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000737:chemistry*; D002240:Carbohydrate Sequence; D002277:Carcinoma / Q000737:chemistry*; D002462:Cell Membrane / Q000276:immunology; D005753:Gastric Mucosa / Q000737:chemistry; D006801:Humans; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000276:immunology / Q000473:pathology / Q000556:secondary; D008207:Lymphatic Metastasis; D008969:Molecular Sequence Data; D009077:Mucins / Q000737:chemistry*; D009362:Neoplasm Metastasis; D011003:Ploidies; D013274:Stomach Neoplasms / Q000737:chemistry*
chemical_list: D000911:Antibodies, Monoclonal; D015295:Antigens, Tumor-Associated, Carbohydrate; D009077:Mucins