应用RNAi沉默STAT3基因促裸鼠移植瘤细胞凋亡及对Bax/Bcl-2基因表达的影响  

Effect on cell apoptosis and Bax/Bcl-2 gene expression of implanted human breast cancer cells in nude mice by applying RNAi to silence STAT3 gene

作　　者：王禹[1] 张颖超[1] 潘玉琢[1] 赵雪俭[1] 关文曾[1] 

机构地区：[1]吉林大学第二医院基本外科,吉林长春410011

出　　处：《中国普通外科杂志》2005年第4期273-276,共4页China Journal of General Surgery

摘　　要：目的应用RNAi技术沉默信号转导子与转录活化子3(STAT3)基因,探讨其对人乳腺癌裸鼠移植瘤的细胞凋亡及其对Bax/Bcl2基因表达的影响。方法于雌裸鼠皮下种植MCF7细胞,肿瘤长至一定大小时,随机分为盐水对照(A)组、空质粒对照(B)组及实验(C)组。于肿瘤局部分别注射盐水、psilencer1.0U6空质粒和psilencer1.0U6STAT3siRNA重组质粒。当A组肿瘤长至足够大时处死全部动物,取肿瘤,测其大小及重量,行HE及免疫组化染色,同时用Westernblot检测STAT3,Bax,Bcl2基因的表达水平。结果C组肿瘤瘤块的体积和重量明显小于A,B组(P<0.01)。免疫组化及HE显示C组肿瘤中心区出现大面积细胞坏死及细胞凋亡征象,STAT3免疫组化呈阴性,而A,B组无此现象。Westernblot显示C组STAT3的表达明显低于A,B组(P<0.01),而Bax的表达明显高于A,B组(P<0.05),各组Bcl2的表达水平差异无显著性(P<0.05)。结论应用RNAi技术沉默STAT3基因可以降低人乳腺癌裸鼠移植瘤中STAT3的表达,同时引起Bax基因的表达上调,导致细胞凋亡进而抑制肿瘤的生长。Objective To discuss the effect on cell apoptosis and Bax/Bcl-2 gene expression of nude mice model with implanted human breast cancer cells by applying RNAi technique to silence signal transducers and activators of transcription 3 (STAT3)gene.Methods MCF-7 breast cancer cells were implanted under the skin of female nude mice. After the tumors grew to a definite size,the mice were randomly divided into three groups:saline control group(A), empty plasmid group(B), the experimental group(C). The tumors were respectively injected with saline, empty plasmid with psilencer1.0-U6, and recombined plasmid with ~psilencer 1.0-U6-stat3-siRNA . When the growth of group A animals reached the sufficient size,all of the animals were killed, the tumors were taken out, their size and weight were measured,immunohistochemical(IHC) analysis was done, and protein expression of STAT3, Bax and Bcl-2 gene in tumors were examined by Western blot. Results The size and weight of tumors in group C were significantly lower than group A and group B. (P<0.01). Immunohistochemical analysis and microscopic examination showed that there was a large area of cytoclasis and signs of cell apoptosis in the center of tumors of group C, and the STAT3 Immunohistochemistry result of the center was negative but that of the border area was positive; there were no such phenomena in group A and group B. The results of Western blot analysis showed that protein expressions of STAT3 gene in group C were significantly lower than those in group A and group B (P<~0.01 ), but there were no significant differences between group A and group B(P>0.05), and protein expressions ofBax gene in tumor of group C were significantly higher than those in group A and group B (P<0.05),but there were no significant differences between group A and group B (P>0.05).The protein expressions of Bcl-2 gene in all groups showed no significant differences (P>0.05). Conclusions Silencing STAT3 gene can decrease STAT3 gene expressions , increase Bax gene

关 键 词：乳腺肿瘤/遗传学 细胞调亡 基因表达 基因 Bax 基因 Bcl一2 RNAi技术 转录活化子3 沉默信号转导子 

分 类 号：R730.23[医药卫生—肿瘤] R737.9[医药卫生—临床医学]