摘要
目的 确定结肠癌细胞中真核细胞起始因子 4E(eukaryoticinitiationfactor 4E ,eIF 4E)是否在帽依赖翻译水平上调控乙酰肝素酶的表达 ,并对乙酰肝素酶表达和肿瘤细胞侵袭性改变的相关性进行探讨。方法 采用Westernblot和RT PCR方法 ,分别检测eIF 4E被阻抑后其转录和翻译水平的改变。乙酰肝素酶活力是以其将大分子放射性元素 (3 5 S)标记硫酸乙酰肝素底物降解为小分子的能力来确定。癌细胞侵袭力改变使用膜浸润培养系统来检测。结果 反义寡核苷酸 (asODN)经脂质体转染LS 174T细胞后 ,eIF 4E基因表达明显抑制 ,其蛋白表达也显著下降。伴随eIF 4E被阻抑 ,LS 174T细胞乙酰肝素酶的活力和蛋白表达量均下降 ,并伴有癌细胞体外侵袭力的下降。结论 eIF 4E在翻译步骤对乙酰肝素酶表达具有调控作用 。
Objective To determine whether the eukaryotic initiation factor-4E(eIF-4E) is involved i n the cap-dependent translationa l regulation of heparanase and study the correlation between heparanase expressi on and metastatic potential of LS-174T cells. Methods The protein and mRNA levels of inhibited eIF-4E were tested by Western blot and RT-PCR. Heparanase activ ity was defined as the ability to degrade high molecular weig ht(40- 100 000 ) radiolabeled( 35 S) heparan sulfate (HS) substrate into low m olecular weight(5-15 000) HS fragments. The invasive potential of tumor cells i n vitro was observed by Matrigel invasion assay system. Results The 20-mer antisense oligonucleotide (asODN) a gainst eIF-4E specifically and significantly inhibited eIF-4E expression at bo th transcriptional and translational levels. The expression and the activ ity of heparanase were effectively lowered,which further decreased the invasive potential of LS-174T. Conclusion eIF-4E, probably being involved in translational regulation of heparanase in colon adenocarcinoma cell line LS-174T, can be a particularly interesting targe t for heparanase regulation, based on of its critical function.
出处
《中华肿瘤杂志》
CAS
CSCD
北大核心
2003年第6期542-545,共4页
Chinese Journal of Oncology
基金
广东省自然科学基金资助项目 ( 0 1 0 6 43)
国家骨干教师基金资助项目( 2 0 0 2 0 6 0 3)
