The mechanism and biological function of abnormal expression of fucosylated carbohydrate chains occurring after development of endometrial cancer

本研究旨在（1）分析子宫内膜癌细胞恶性转化后岩藻糖基转移酶（FT）的定量和定性变化，（2）阐明岩藻糖基化糖链在子宫内膜癌细胞转移中的作用.基于刘易斯^b型碳水化合物链（Le^B）的表达，将培养的子宫内膜癌SNG-II细胞分为两个亚系：（a）SNG-S细胞，其强烈表达Le^B并且表现出增加的α 1 - 4 FT（FTIII）活性，其参与Le^B的合成;和（B）SNG-W细胞，其不具有Le^B并且FTIII活性降低。使用FTIII cDNA的北方印迹转移技术研究FTIII mRNA在SNG-II、SNG-S和SNG-W细胞中的表达，结果显示只有SNG-II和SNG-S表达FTIII mRNA。 ...更多信息 糖基转移酶mRNA表达增加引起的糖基转移酶蛋白水平升高。采用原位粘附试验评价SNG-S和SNG-W细胞与人脐静脉内皮细胞（HUVEC）的粘附能力以及抗体抑制这种粘附的能力。不表达Le^B分子但表达其前体H_1型糖链（H_1）的SNG-W细胞对HUVEC的亲和力约为SNG-S细胞的两倍。抗H1抗体可抑制SNG-W细胞与HUVEC的粘附，并呈剂量依赖性。将具有高转移能力的SNG-W细胞注射到抗H1或抗H2抗体处理的裸鼠尾静脉，8周后抗H2抗体处理组的肺转移率为36.7%，而抗H2抗体处理组的肺转移率为13.3%。这些结果表明，H_1在SNG-W细胞的血管粘附和远处转移能力中起重要作用。用H_1微球在血管内皮上寻找H_1的配体。用IL-1 β预处理子宫内膜细胞，H_1珠与子宫内膜细胞的粘附增加6倍，表明血管内皮上H_1的配体是一种粘附分子，其表达通过IL-1 β处理而增加。少

The present study was conducted to (1) analyze quantitative and qualitative changes in fucosyltransferase (FT) occurring after malignant transformation of endometrial cells and (2) elucidate the role of fucosylated carbohydrate chains in endometrial cancer cell metastasis.1. Cultured endometrial cancer SNG-II cells were divided into two sublines based on expression of Lewis^b-type carbohydrate chains (Le^b) : (a) SNG-S cells which strongly express Le^b and exhibit increased activity of alpha1-4FT (FTIII), which is involved in the synthesis of Le^b, and (b) SNG-W cells with no Le^b and decreased FTIII activity. Investigation of the expression of FTIII mRNA in SNG-II,SNG-S,and SNG-W cells using the Northern blot transfer technique with FTIII cDNA showed that only SNG-II and SNG-S express FTIII mRNA.These results indicate that the rise in glycosyltransferase activity responsible for abnormal carbohydrate chain expression following malignant change is partly attributable to an increase in … More glycosyltransferase protein levels caused by increased expression of glycosyltransferase mRNA.2. The ability of SNG-S and SNG-W cells to adhere to human umbilical vein endothelial cells (HUVEC) and the capacity of antibodies to inhibit such adhesion were evaluated using in situ adhesion assay. The adhesiveness to HUVEC of SNG-W cells, which do not express Le^b molecules but do express their precursor H_1-type carbohydrate chains (H_1), was approximately double that of SNG-S cells. Adhesion of SNG-W cells to HUVEC was inhibited by anti-H_1 antibody in a dose-dependent manner. When SNG-W cells with high metastatic ability were injected into the tail vein of nude mice treated with anti-H_1 or anti-H_2 antibody, 36.7% of the animals treated with anti-H_2 antibody developed pulmonary metastasis after 8 weeks versus 13.3% of those treated with anti-H_2 antibody. These findings show that H_1 plays an important role in the ability of SNG-W cells to adhere to blood vessels and to metastasize distantly. The ligand for H_1 on the vascular endothelium was sought using H_1 beads. Adhesion of H_1 beads to endometrial cells increased 6-fold when the cells were pretreated with IL-1beta, suggesting that the ligand for H_1 on the vascular endothelium is an adhesion molecule whose expression is increased by treatment with IL-1beta. Less