Jankovic Miroslava M, Milutinovic Bojana S
Institute for the Application of Nuclear Energy-INEP, University of Belgrade, Banatska 31b, 11080 Zemun, Serbia.
Cancer Biomark. 2008;4(1):35-42. doi: 10.3233/cbm-2008-4104.
CA125, a coelomic epithelium-related antigen, is expressed in both normal and pathological conditions. In this study, we compared the glycosylation of CA125 antigen from amniotic fluid and the ovarian carcinoma cell line OVCAR-3, in order to detect possible differences as a specific marker of their origin. Antigens from both sources were radiolabelled and subsequently subjected to the affinity chromatography, using plant lectins differing in carbohydrate specificity as ligands. A common chromatographic scheme was applied to all columns, i.e. they were eluted with: a) washing buffer to wash out non-bound and low-affinity bound fractions, b) a solution of inhibitory sugar and c) a low pH buffer, to release the high affinity bound fractions. CA125 antigen from each source was found to be heterogeneous in respect to the existence of multiple glycoforms, with O-linked glycan chains predominating. However, the binding patterns of both N- and O-linked glycan-reactive lectins indicated distinct differences in carbohydrate composition between CA125 antigen isolated from amniotic fluid and OVCAR-3 cell line. The observed specificites of CA125-oligosaccharide chains might be of special importance from the biomedical aspect, in terms of their possible use for clinical evaluation of gynecological functions in health and disease.
CA125是一种与体腔上皮相关的抗原，在正常和病理条件下均有表达。在本研究中，我们比较了羊水和卵巢癌细胞系OVCAR-3中CA125抗原的糖基化情况，以检测其作为起源特异性标志物的可能差异。对来自两种来源的抗原进行放射性标记，随后使用具有不同碳水化合物特异性的植物凝集素作为配体进行亲和层析。所有柱都采用相同的层析方案，即先用：a) 洗涤缓冲液洗去未结合和低亲和力结合的部分，b) 抑制糖溶液，c) 低pH缓冲液，以释放高亲和力结合的部分。发现来自每种来源的CA125抗原在多种糖型的存在方面具有异质性，其中O-连接聚糖链占主导。然而，N-连接和O-连接聚糖反应性凝集素的结合模式表明，从羊水和OVCAR-3细胞系分离的CA125抗原在碳水化合物组成上存在明显差异。就CA125寡糖链在健康和疾病状态下用于妇科功能临床评估的可能用途而言，所观察到的特异性可能从生物医学角度具有特殊重要性。
