Glycobiological Study of Malignant Tumors in Ophthalmology

采用凝集素组织化学和原位杂交组织化学方法，用唾液转移酶（ST）的cRNA探针分析了眼睑和眼窝各种恶性肿瘤的糖结合物。我们认为，这些细胞在细胞质中表达了ST-mRNA的分布，并在细胞表面表达了唾液酸特异性凝集素的结合，从而积极地产生了唾液聚糖。我们还认为，表面被凝集素染色而细胞质中没有ST-mRNA分布的细胞已经完成了唾液聚糖的合成。基于这些观点，这种糖组织化学技术可用于单个肿瘤细胞中糖结合物的动态分析。这项技术揭示了在脂流变性角化病肿瘤中，转化率较慢的o链唾液聚糖可能分布在增厚的脊髓细胞层细胞上，并参与了其病理机制。我们也用这种方法分析了眼睑基底细胞癌和泪多形性腺瘤。MUC 1是一种o链糖缀合物，在所有眼睑鳞状细胞癌和皮脂腺癌的肿瘤细胞中均有免疫组织化学检测到，而在所有基底细胞癌和眼睑恶性肿瘤中均未检测到。这些发现提示MUC 1可能参与包括转移在内的恶性特征的表达。另一方面，Ki 67抗原在眼睑恶性肿瘤中的表达率高于良性肿瘤，提示Ki 67可用于区分眼睑恶性肿瘤和良性肿瘤。角蛋白的免疫组化分布显示眼睑基底细胞癌是由统一的肿瘤细胞组成，所有肿瘤细胞都表达相同的角蛋白，而鳞状细胞癌和皮脂腺癌则是由多种分化的肿瘤细胞组成。

The glycoconjugates in various malignant tumors in eyelids and orbita were analyzed by lectin histochemistry and in situ hybridization histochemistry using cRNA probes for sialiltransferases (ST). We considered that the cells, which expressed both cytoplasmic distribution of ST-mRNA and binding of lectins, specific for sialic acids, to the cell surfaces, were actively producing sialoglycans. We also considered that the cells, whose surfaces were stained with the lectins without cytoplasmic distribution of ST-mRNA,have completed the synthesis of sialoglycans. Based on these view points, this glycohistochemical technique is useful for dynamic analysis of the glycoconjugates in individual tumor cells. This technique revealed that O-linked sialoglycan, whose turnover-rate is slow, may be distributed over the cells of thickened spinocellular layr in the tumor of seborrheic keratosis and involved in its pathomechanism. We also analyzed the basal cell calcinoma in eyelids and the lacrimal pleomorphic adenoma using this method.MUC 1, one of the O-linked glycoconjugates, was immunohistochemically detected in the tumor cells of all cases of squamous cell carcinoma and sebaceous carcinoma in eyelids whereas it was absent in those of all cases of basal cell carcinoma and benigh tumors in eyelids. These findings suggested that MUC 1 may be involved in expression of malignant features including metastasis. On the other hand, the Ki 67 antigen-expression rates of malignant eyelid tumors were higher than those of benigh tumor, suggesting that Ki 67 can be used to distinguish between malignant and benigh tumors. Immunohistochemical distribution of kearatin revealed that the basal cell carcinoma in eyelids is consisted of uniform tumor cells, all of which express the same keratin, while the squamous cell carcinoma and sebaceous carcinoma are composed of various differentiatiating tumor cells.