Expression of Tn, sialosyl-Tn, and T antigens in human colon cancer.
作者:SH Itzkowitz, Mei Yuan, Carolyn K. Montgomery, Thomas Kjeldsen, Hiroaki Takahashi, W. L. Bigbee, Y S Kim · 发表于:PubMed · 年份:1989 · 被引用次数:516 · 研究领域:Glycosylation and Glycoproteins Research、Cholangiocarcinoma and Gallbladder Cancer Studies、Monoclonal and Polyclonal Antibodies Research
Mucin glycoproteins are major secretory products of the colon and contain O-linked oligosaccharides synthesized on a polypeptide backbone. The initial step in the synthesis of O-linked oligosaccharides is the addition of N-acetylgalactosamine to serine or threonine residues forming the Tn antigen. This substance can then receive additional carbohydrate residues such as sialic acid to form sialosyl-Tn antigen, or galactose to form T antigen. In the colon, the T antigen is an oncodevelopmental cancer-associated antigen but little is known about Tn and sialosyl-Tn expression. The present comparative immunohistochemical study was performed to analyze the expression of these antigens in fetal, normal adult, and malignant colorectal tissues with an aim toward elucidating whether Tn and sialosyl-Tn are also oncodevelopmental colon cancer-associated antigens and to gain insight into the earliest steps of mucin glycosylation in colonocytes. We used three reagents to detect Tn antigen (two monoclonal antibodies ETn1.01 and CU-1, and one lectin Vicia villosa), two reagents to detect sialosyl-Tn (monoclonal antibodies TKH2 and B72.3) and one to detect T antigen (monoclonal antibody AH9-16). Except for occasional reactivity with VVA and CU-1, cells of normal colonic mucosa did not express Tn, sialosyl-Tn, or T antigens. However, in the transitional mucosa immediately adjacent to cancer, all three antigens were expressed (ranging from 35 to 67% of cases depending upon the reagent). In colo...