MOLECULAR NATURE AND POSSIBLE PRESENCE OF A MEMBRANOUS GLYCAN-PHOSPHATIDYLINOSITOL ANCHOR OF CA125-ANTIGEN
MOLECULAR NATURE AND POSSIBLE PRESENCE OF A MEMBRANOUS GLYCAN-PHOSPHATIDYLINOSITOL ANCHOR OF CA125-ANTIGEN
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DOI：
10.1159/000217716
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发表时间：
1991-09-01
期刊：
影响因子：
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通讯作者：
KOMODA, T
中科院分区：
文献类型：
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作者：
NAGATA, A;HIROTA, N;KOMODA, T
研究了 CA125 分子中聚糖-磷脂酰肌醇锚 (GPI-锚) 的分子性质和可能存在。连续凝集素亲和层析和N-或O-聚糖酶处理以降低抗原性表明CA125分子中含有某些N-和O-糖基化糖链，就像糖蛋白一样。磷脂酰肌醇特异性磷脂酶 C (PI-PLC) 治疗后，卵巢癌组织释放的 CA125 随时间依赖性增加，同时释放组织非特异性碱性磷酸酶。经过 PI-PLC 处理的 CA125 的蛋白质印迹显示出 90 kD 的单个条带，而不是天然抗原的 162 kD 和 76 kD 带。此外，经过PI-PLC处理的卵巢癌组织失去了OC125抗体对CA125的免疫组织化学定位。因此，强烈建议CA125是一种具有N-和O-连接糖链以及膜GPI锚定部分的糖蛋白，并且进一步，其90-kD形式是没有GPI锚定的抗原。
The molecular nature and possible presence of a glycan-phosphatidylinositol anchor (GPI-anchor) in CA125 molecules was investigated. Serial lectin affinity chromatography and N- or O-glycanase treatment to reduce antigenicity showed that CA125 contained certain N- and O-glycosylated sugar chains in the molecule, like a glycoprotein. CA125 released from ovarian cancer tissues increased time-dependently following phosphatidylinositol-specific phospholipase C (PI-PLC) treatment, concomitant with the release of tissue-unspecific alkaline phosphatase. Western blotting of CA125 treated by PI-PLC showed a single band of 90 kD instead of the 162- and 76-kD bands of the native antigen. Further, ovarian cancer tissues subjected to PI-PLC treatment lost the immunohistochemical localization of CA125 with OC125 antibody. Consequently, it is strongly suggested that CA125 is a glycoprotein that has both N- and O-linked sugar chains and a membranous GPI-anchoring moiety, and further, that its 90-kD form is the antigen without the GPI-anchor.