MicroRNA143调节结肠癌细胞KRAS蛋白的表达  

MicroRNA143 regulates the expression of KRAS protein in colorectal carcinoma cells

作　　者：刘宏[1] 张苏展[2] 蔡善荣[2] 陶思丰[2] 董琦[2] 

机构地区：[1]山西医科大学第一医院,山西太原030001 [2]浙江大学医学院第二附属医院肿瘤研究所,浙江杭州310006

出　　处：《中国病理生理杂志》2008年第8期1506-1509,共4页Chinese Journal of Pathophysiology

基　　金：中国博士后基金资助项目(No.20060391059)

摘　　要：目的:探讨结肠癌细胞中microRNA143(miR-143)对KRAS蛋白表达的影响及其作用机制。方法:从基因组DNA中克隆pri-miR-143基因,构建miR-143的表达载体。miR-143转染结肠癌细胞系SW480,用Northern blotting方法测定miR-143水平的变化,通过RT-PCR和Western blotting方法检测转染细胞中KRAS基因的表达。构建含miR-143结合位点的荧光素酶报告载体,与miR-143表达载体共转染,检测细胞中的荧光素酶活性。结果:基因转染的SW480细胞中miR-143的表达显著升高,KRAS蛋白的表达水平下降约40%,KRAS mRNA则未受影响。miR-143表达载体与含miR-143结合位点的报告载体共转染可以抑制细胞中的荧光素酶活性。结论:结肠癌细胞中microRNA143在转录后水平抑制KRAS蛋白的表达。AIM： To investigate the effects of microRNA143 （miR - 143 ） on the expression of KRAS oncogene in colorectal carcinoma cells. METHODS ： Pri - miR - 143 gene was amplified from genomic DNA by PCR. A miR - 143 expression vector was constructed and transfected into a human colon adenocarcinoma cell line SW480. The levels of miR -143 were evaluated by Northern blotting. RT- PCR and Western blotting were used to examine the expression of KRAS oncogene in transfected cells. Various pGL3 reporter plasmids containing miR - 143 complementary site were constructed, and then co -transfected into SW480 cells with miR - 143 expression plasmids. The luciferase activities were determined. RESULTS： In transfected cells, the increased accumulation of miR - 143 resulted in approximately 40% decrease in KRAS protein levels, but had no effect on level of KRAS mRNA. Co - transfection of miR - 143 expression plasraids and pGL3 reporter plasmids into SW480 inhibited luciferase activity, compared with pGL3 reporter plasmids transfection alone. CONCLUSION： MicroRNA143 specially suppresses the expression of KRAS protein at the post -transcriptional level in colorectal carcinoma cells.

关 键 词：MICRORNA 结直肠肿瘤 SW480细胞 蛋白质KRAS 

分 类 号：R363[医药卫生—病理学]