FUNCTIONS OF (1,3) FUCOSYLTRANFERASE GENE FAMILY

癌细胞通过血流的转移显著地影响了肿瘤的生长。 大多数人类恶性肿瘤的诊断、治疗和预后。 肿瘤细胞与微血管系统的相互作用取决于许多因素， 因素，但转移性侵袭显然需要逮捕和坚持， 细胞向内皮细胞迁移，然后迁移和/或增殖。 通过细胞因子激活内皮细胞增加某些细胞的粘附， 人黑色素瘤和腺癌细胞体外通过不同的过程 整合素介导的相互作用。最近的实验表明， 岩藻糖基化结构sialyl刘易斯x可以介导 白细胞对E-选择素（ELAM-1）和P-选择素（GMP-140/PADGEM）的敏感性 由人内皮细胞表达。一种相关的聚糖，唾液酸刘易斯a， 也可以作为E-选择素的配体。这些碳水化合物 最初被描述为肿瘤发育抗原， 一些相同的恶性细胞现在显示出粘附于精氨酸激活的 内皮细胞 遗传和生化数据表明至少有六种 人类中能够产生α（1，3）岩藻糖基转移酶（FT）的基因 这些相关的聚糖。虽然组织特异性表达已经被证实是 证明了岩藻糖基化低聚糖抗原和多种 α（1，3）FT活性，决定这一过程的分子机制 并没有得到很好的理解。 我们已经分离并鉴定了四个人α（1，3）FT基因， 现在将用于以下具体目标所概述的实验： 1.分离并表征剩余的α（1，3）和α（1，4）FT基因。 2.确定人类染色体上α（1，3）FT基因座的物理图谱。 3.确定正常表达模式的α（1，3）FT转录本， 人体组织4.检查人中α（1，3）FT转录本的表达 腺癌细胞能够粘附到腺嘌呤激活的 内皮细胞证明特异性α（1，3）或α（1，4）FT基因 参与，与FT活性和寡糖配体相关 表达，增加评估选择素受体结合。定义分子 恶性细胞粘附事件中糖聚糖表达的基础 可能与转移和FT调节机制有关。

Metastasis of cancer cells via the bloodstream significantly affects the diagnosis, treatment, and prognosis of most human malignancies. Interaction of tumor cells with the microvasculature depends on many factors, but metastatic invasion clearly requires arrest and adherence of the cell to endothelium, followed by migration and/or proliferation. Activation of endothelial cells by cytokines increases adhesion of some human melanoma and adenocarcinoma cells in vitro by a process distinct from integrin-mediated interactions. Recent experiments have shown that the fucosylated structure sialyl Lewis x can mediate adhesion of leukocytes to E-selectin (ELAM-1) and P-selectin (GMP-140/PADGEM) expressed by human endothelial cells. A related glycan, sialyl Lewis a, can also serve as a ligand for E-selectin. These carbohydrate moieties were originally described as oncodevelopmental antigens associated with some of the same malignant cells now shown to adhere to cytokine-activated endothelium. Genetic and biochemical data suggest the presence of at least six alpha(1,3)fucosyltransferase (FT) genes in humans capable of generating these related glycans. Although tissue specific expression has been demonstrated for fucosylated oligosaccharide antigens and multiple alpha(1,3)FT activities, molecular mechanisms that determine this process are not well understood. We have isolated and characterized four human alpha(1,3)FT genes, which will now be used for experiments outlined in the following specific aims: 1. Isolate and characterize remaining alpha(1,3) and alpha(1,4)FT gene(s). 2. Determine the physical maps of alpha(1,3)FT loci on human chromosomes. 3. Determine normal expression patterns of alpha(1,3)FT transcripts in human tissues. 4. Examine expression of alpha(1,3)FT transcripts in human adenocarcinoma cells capable of adhering to cytokine-activated endothelium. Demonstrate the specific alpha(1,3) or alpha(1,4) FT gene(s) involved, correlate with FT activity and oligosaccharide ligand expression, add assess selectin receptor binding. Defining the molecular basis of carbohydrate glycan expression in malignant cell adhesion events may link observations about metastasis and FT regulatory mechanisms.