Lloyd K O, Travassos L R, Takahashi T, Old L J
J Natl Cancer Inst. 1979 Sep;63(3):623-34. doi: 10.1093/jnci/63.3.623.
Cell surface glycoproteins of human tumor cell lines (melanomas and astrocytomas, and ovarian, bladder, stomach, cervical, laryngeal, and renal cancers) were studied by labelling with 1) neuraminidase-galactose oxidase-[3H]borohydride, 2) galactose oxidase-[3H]borohydride, and 3) dilute periodate-[3H]borohydride. The labeled components were examined by polyacrylamide gel electrophoresis and fluorography. Each tumor type had a distinctive pattern of labeled glycoproteins when the results from both procedures 1 and 2 were considered. Cell surface glycoproteins of malignant melanoma could not be labeled by procedure 2, whereas the other cell lines had at least two major glycoproteins that could be labeled by this method. Very similar profiles of melanoma glycoproteins were labeled by procedures 1 and 3. From these results the conclusion was reached that cell surface glycoproteins of melanomas are substituted with sialic acid so that their D-galactose and/or N-acetyl-D-galactosamine residues are available for oxidation by galactose oxidase only after neuraminidase treatment. An alternative explanation that these sugars are sterically accessible to galactose oxidase only after neuraminidase treatment also has to be considered. All melanoma lines studied were characterized by having two major cell surface glycoproteins with molecular weights of 110,000 and 90,000, respectively. Lines, however, varied considerably in their expression of other components. In particular, heterogeneity was shown in the expression of gp220, a component identified as fibronectin by immunoprecipitation with a specific antiserum, and in the expression of gp37/32, a pair of glycoproteins having the characteristics of la-like antigens. Of the other cell lines studied, astrocytomas most closely resembled melanoma in their glycoprotein profiles. The brain tumors, however, had two or three glycoproteins, including gp110, which could be labeled by galactose oxidase-[3H]borohydride without neuraminidase treatment.
通过用以下方法标记，对人肿瘤细胞系（黑色素瘤、星形细胞瘤以及卵巢癌、膀胱癌、胃癌、宫颈癌、喉癌和肾癌）的细胞表面糖蛋白进行了研究：1）神经氨酸酶 - 半乳糖氧化酶 - [³H]硼氢化钠；2）半乳糖氧化酶 - [³H]硼氢化钠；3）稀高碘酸盐 - [³H]硼氢化钠。通过聚丙烯酰胺凝胶电泳和荧光自显影检查标记的成分。当考虑方法1和方法2的结果时，每种肿瘤类型都有独特的标记糖蛋白模式。恶性黑色素瘤的细胞表面糖蛋白不能用方法2标记，而其他细胞系至少有两种主要糖蛋白可以用这种方法标记。方法1和方法3标记的黑色素瘤糖蛋白谱非常相似。从这些结果得出的结论是黑色素瘤的细胞表面糖蛋白被唾液酸取代，因此只有在神经氨酸酶处理后，它们的D - 半乳糖和/或N - 乙酰 - D - 半乳糖胺残基才能被半乳糖氧化酶氧化。还必须考虑另一种解释，即这些糖只有在神经氨酸酶处理后才在空间上可被半乳糖氧化酶接近。所有研究的黑色素瘤细胞系的特征是有两种主要的细胞表面糖蛋白，分子量分别为110,000和90,000。然而，不同细胞系在其他成分的表达上有很大差异。特别是，通过用特异性抗血清进行免疫沉淀鉴定为纤连蛋白的成分gp220的表达以及具有la样抗原特征的一对糖蛋白gp37/32的表达存在异质性。在所研究的其他细胞系中，星形细胞瘤在糖蛋白谱方面与黑色素瘤最相似。然而，脑肿瘤有两到三种糖蛋白，包括gp110，在未经神经氨酸酶处理的情况下可以被半乳糖氧化酶 - [³H]硼氢化钠标记。
