【摘要】 岩藻糖基转移酶(fucosyltransferases,FUTs)是一类催化糖蛋白和糖脂发生岩藻糖基化(修饰)酶,主要包括FUT1~FUT9。已有研究证明,很多癌组织中都有不同FUT基因表达升高的现象。本研究证明,表皮鳞癌细胞的增殖能力与几种FUT基因表达水平有关。本文比较研究了人表皮鳞癌A431和SCC12细胞的增殖速度和几种FUT的表达状况,以揭示鳞癌细胞增殖能力与几种FUT基因表达水平的关系。细胞倍增时间结合MTT法揭示,鳞癌A431细胞的倍增时间约为26 h,而鳞癌SCC12细胞的倍增时间约为33 h(P<0.05),提示A431细胞增殖速度比SCC12细胞明显加快。与增殖速度一致的是,Western印迹显示,A431细胞中与DNA合成相关的增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)蛋白表达水平比SCC12细胞高。实时定量PCR(q PCR)检测FUT1-9基因mRNA转录本,揭示A431细胞中几种FUT基因的mRNA水平均显著高于SCC12细胞。凝集素免疫印迹法和Western印迹法进一步证明,A431细胞中总蛋白的岩藻糖基化水平比SCC12细胞中的明显升高。敲低FUT4基因表达后,A431细胞中Le Y寡糖的表达水平下调,细胞增殖被明显抑制。这些结果证明,较强的表皮鳞癌细胞增殖能力可能与几种FUT基因的高表达,以及糖蛋白的岩藻糖基化(修饰)相关。岩藻糖基转移酶表达水平与临床表皮鳞癌的恶性增生的相关性有待进一步证明。更多还原

【Abstract】 Fucosyltransferases(FUTs) including FUT1 ~ FUT9 are responsible for adding the fucosyl residue to oligosaccharides,glycoproteins and glycolipids,i.e.,fucosylation.It has been shown that FUTs are highly expressed in a variety of cancers.In this study,we have compared human epidermalsquamous carcinoma A431 cell with SCC12 cell for its cellular proliferation and expression of the FUT genes and found that proliferation capability of squamous carcinoma cells is associated with the expression of fucosyltransferases.MTT assays revealed that the cell doubling time for A431 cells and SCC12 cells was approximately 26 and 33 hours,respectively,indicating A431 cells grew faster than SCC12 cells.In consistence with proliferation,Western blot assays showed that the levels of proliferating cell nuclear antigen(PCNA),which is required for DNA synthesis and gap-filling,were much higher in A431 cells than that in SCC12 cells.Furthermore,q PCR assay demonstrated that the levels of FUT1 ~ FUT9transcripts(mRNAs) were higher in A431 cells than that in SCC12 cells.Moreover,Lectin blot and Western blot assays showed higher levels of total protein fucosylation in A431 than that in SCC12.Knockdown of FUT4 by RNA interference(RNAi) resulted in down-regulation of Le Y oligosaccharide and inhibition of A431 cell proliferation.These results suggested that cellular proliferating capability of squamous carcinoma cells could be attributed to the high expression of FUT genes and hyper-fucosylation of glycoproteins.The correlation of fucosyltransferases with the malignant proliferation of squamous carcinomas in patients needed to be investigated in the future.更多还原