Development of a New Diagnostic Method for Thyroid Carcinoma by Measurement of Lectin Inhibitory Thyroglobulin

胸腺球蛋白(TG)是由甲状腺产生的，分子质量为66万道尔顿，碳水化合物含量约为10%。用刀豆蛋白A、晶状体凝集素(LCA)、草甘膦凝集素和蓖麻凝集素-120对良、恶性疾病患者甲状腺组织和血清标本进行了甘油三酯的凝集素亲和结合分析。良、恶性甲状腺组织提取液及血清中凝集素反应性甘油三酯(LCA)占总甘油三酯(Tg)的百分比有显著差异，而与其他凝集素无显著差异。恶性肿瘤组织和血清中LCA反应性甘油三酯的百分率呈下降趋势，尤其是有淋巴结转移的甲状腺癌组织中LCA反应性甘油三酯的百分率显著升高。这是首次研究表明在临床确诊的甲状腺肿瘤中，甘油三酯的微观异质性与其糖链结构的差异，以试图识别甲状腺恶性肿瘤。甘油三酯的不同LCA图谱提示其在鉴别恶性疾病方面具有潜在的重要临床价值。

Thyloglobulin (Tg) is produced by the thyroid with a molecular mass of 660,000 Dalton and a carbohydrate content of approximately 10%. Lectin affinity binding profile of Tg was carried out on samples obtained from thyroid tissue and serum from patients with benign and malignant diseases with the use of Concanavalin A, Lens culinaris agglutinin (LCA), Da tura stramonium agglutinin, and Ricin us communis agglutinin-120. Difference in percentage of Lens culinaris agglutinin (LCA) reactive Tg to total Tg was detected in thyroid tissue extract, as well as in serum from patients with the benign and malignant conditions, however, no significant differences were found with other lectins. The percentage of LCA reactive Tg in tissue and serum had a tendency to decrease in the malignant cases, particularly in patients with thyroid cancer having the lymph node metastasis in that significantly highly percentage ratio of LCA-reactive Tg had been demonstrated. This is the first study to show the differences in microheterogeneity of Tg, with respect to its sugar chain structure in clinically confirmed thyroid tumors in an attempt to identifying thyroid malignancies. The differences LCA profiling of Tg indicate its potential important clinical utility in discriminating of malignant conditions.