Expression of galectin-3 and its clinical application to preoperative cytological diagnosis in thyroid neoplasms

Galectin-3是β-半乳糖苷结合蛋白家族的一员，在细胞间粘附和细胞-基质相互作用中起重要作用，在多种肿瘤病变中表达。据报道，Galectin-3影响肿瘤的进展和转移。我们研究了galectin-3在各种甲状腺肿瘤中的表达。使用抗半乳糖凝集素-3抗体在免疫化学染色的标本中评价半乳糖凝集素-3的表达。通过使用染色面积和浓度计算半乳糖凝集素-3染色评分。69例滤泡性腺瘤、62例滤泡性癌和115例乳头状癌的平均染色评分分别为0.061、0.427和1.514。滤泡性癌的Galectin-3染色积分显著高于滤泡性腺瘤，乳头状癌的Galectin-3染色积分显著高于滤泡性腺瘤或癌，且有淋巴结转移的乳头状癌原发灶Galectin-3表达高于无淋巴结转移的原发灶。galectin-3在正常甲状腺组织中的表达很少。Galectin-3在3种组织学类型中的表达差异有统计学意义。根据这些结果，我们假设galectin-3在甲状腺肿瘤增殖的不同阶段以不同的方式起作用。此外，我们检测了galectin-3在甲状腺肿瘤残端细胞学标本中的表达。Galectin-3在细胞学标本和石蜡切片标本中也有较好的表达。因此，galectin-3的表达有可能适用于甲状腺肿瘤的术前细胞学诊断。

Galectin-3 is a member of the β-galactoside-binding protein family which plays an important role in cell-cell adhesion and in cell-matrix interaction and is expressed in many neoplastic lesion. It is reported that Galectin-3 influences to the progression and metastasis. We examined expression of galectin-3 in various thyroid neoplasms. Expression of galectin-3 was evaluated in immunohistochemically stained specimen using anti-galectin-3 antibody. A galectin-3 staining score was calculated by using stained area and concentration. Mean staining score was respectively 0.061, 0.427, and 1.514 in 69 lesions of follicular adenomas, 62 of follicular carcinomas, and 115 of papillary carcinomas. Staining score was significantly higher in the follicular carcinomas than in the follicular adenomas and was significantly higher in the papillary carcinomas than in the follicular adenomas or carcinomas.Furthermore, primary lesion of papillary carcinomas with lymph node metastases expressed higher concentration of galectin-3 than that without metastases. Expression of galectin-3 was rarely found in normal thyroid tissues. Galectin-3 expression was significantly different in 3 histological types. From these results, we assumed that galectin-3 works in different ways at different stages of thyroid neoplasm proliferation.Moreover, we examined expression of galectin-3 in a stump cytology specimen of thyroid tumor. Galectin-3 was also well expressed in cytological specimens as same as paraffin-bedded specimens. Therefore, there is a possibility that expression of galectin-3 is applicable to use for preoperative cytological diagnosis of thyroid gland tumor.