Carbohydrate antigen expression in the adenoma-carcinoma sequence.
Carbohydrate antigen expression in the adenoma-carcinoma sequence.
复制标题
腺瘤-癌序列中碳水化合物抗原的表达。
DOI：
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发表时间：
1988
期刊：
影响因子：
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通讯作者：
S. Itzkowitz
中科院分区：
文献类型：
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作者：
Y. Kim;S. Itzkowitz
结肠癌中可能会发生碳水化合物抗原表达的几种改变。诸如扩展 LeX 和 LeY 抗原之类的修饰结构可以作为人类结肠中的癌症相关抗原，尽管没有一种抗原仅针对结肠癌。由于 LeX 和 LeY 抗原存在于胎儿组织中，但不存在于成人正常组织中，因此这些抗原本质上似乎是肿瘤发育的。具有内部岩藻糖基化或末端唾液酸化的延伸LeX和LeY抗原在结肠癌中的表达被认为具有相当的癌症特异性，因为正常结肠粘膜不表达这些抗原。此外，这些分子也可能是癌前病变的“标志物”，因为腺瘤性息肉而非增生性息肉能够表现出这些变化，并且抗原表达通常与腺瘤性息肉中的恶性潜能相关。 LeX 和 LeY 表达的这些改变的精确生化和分子机制及其生物学意义目前尚不清楚。然而，负责聚乳糖胺延伸、岩藻糖基化和唾液酸化过程的糖基转移酶的调节可能是异常的。显然，需要进一步的研究来阐明这些机制。然而，针对扩展 LeX 和 LeY 抗原的单克隆抗体似乎是诊断结肠肿瘤的有用辅助手段，并且也可能有助于阐明腺瘤-癌序列中涉及的分子和生化机制。
Several alterations in carbohydrate antigen expression can occur in colon cancers. Modified structures such as extended LeX and LeY antigens could serve as cancer-associated antigens in the human colon, although none is specific only for colon cancer. Since LeX and LeY antigens are present in fetal tissues, but not in adult normal tissues, these antigens appear to be oncodevelopmental in nature. The expression in colon cancers of extended LeX and LeY antigens with internal fucosylation or terminal sialylation is considered rather cancer-specific since normal colonic mucosa does not express these antigens. Furthermore, these molecules may also be "markers" for premalignancy, since adenomatous polyps, but not hyperplastic polyps are capable of exhibiting these changes and antigenic expression often correlates with malignant potential in adenomatous polyps. The precise biochemical and molecular mechanisms for these alterations in LeX and LeY expression and their biological significance are not well understood at the present time. However, it is likely that the regulation of the glycosyltransferase enzymes responsible for the processes of polylactosamine elongation, fucosylation, and sialylation may be aberrant. Obviously further studies are needed to elucidate these mechanisms. However, it appears that the monoclonal antibodies directed against extended LeX and LeY antigens are a useful adjunct in the diagnosis of colonic neoplasia, and may also be helpful in elucidating the molecular and biochemical mechanisms involved in the adenoma-carcinoma sequence.