NEW NMR METHODOLOGY FOR CHAR CARBOHYDRATE PROTEIN INTERACTIONS: DRUG DESIGN

我们实验的目的是了解 癌基因，特别是neu/Her-2癌基因，引起特异性的 乳腺癌细胞中细胞表面寡糖的变化， 确定这些变化是否影响细胞粘附特性。 我们和 其他人已经确定这些寡糖的变化是由 通过增加特定糖基转移酶的活性， N-乙酰葡糖胺基转移酶V或GlcNAc-IV。 已经显示GlcNAc-IV的产物在表面上增加， 成纤维细胞和其它细胞类型。 此外，几个实验室的实验结果表明， 这些寡糖表达的改变会影响 细胞的转移潜能。 因此， 了解乳腺癌中那些已知的癌基因是如何 与晚期乳腺癌相关，如neu/Her-2，改变 GlcNAc-IV活性及其寡糖产物。 我们 我也希望确定这些寡糖的变化是否会影响 对这些细胞的细胞间粘附的影响。 GlcNAc-T V，这种酶 负责合成关键的表面寡糖， 被克隆并转染到人癌细胞系中， 细胞中寡聚N-乙酰乳糖胺的量增加， 更具侵袭性的癌症样表型 一种诱导型质粒已经被 构建其中GlcNAc-IV的表达在一个表达载体的控制下的载体。 无关的诱导物。 初步结果稳定，诱导 由该构建体产生的转化体表现出四倍的 诱导后GlcNAc-IV活性增加。

The aim of our experiments is to understand the mechanism by which oncogenes, particularly the neu/Her-2 oncogene, cause specific cell-surface oligosaccharide changes in breast carcinoma cells and to determine if these changes affect cell adhesion properties. We and others have established that these oligosaccharide changes are caused by an increase in the activity of a particular glycosyltransferase, N-acetylglucosaminyltransferase V or GlcNAc-T V. The oligo-saccharide products of GlcNAc-T V have been shown to increase on the surfaces of fibroblasts and other cell types following oncogenic transformation. Moreover, the results of experiments from several laboratories suggest that alterations in the expression of these oligosaccharides influence the metastatic potential of cells. It is important, therefore, to understand in breast carcinomas how those oncogenes known to be associated with advanced breast cancer, such as neu/Her-2, alter GlcNAc-T V activity and there by its oligosaccharide products. We also wish to determine if these oligosaccharide changes have an effect on the intercellular adhesion of these cells. GlcNAc-T V, the enzyme responsible for synthesizing the critical surface oligosaccharide, has been cloned and transfected into a human carcinoma cell line resulting in increased amounts of oligo-N-acetyllactosamine in the cells and a more aggressive, cancer-like phenotype. An inducible plasmid has been constructed in which expression of GlcNAc-T V is under control of an unrelated inducer. Preliminary results with stable, inducible transformants resulting from this construct exhibit a fourfold increase in GlcNAc-T V activity following induction.