共轭亚油酸单体诱导乳腺癌细胞MCF-7凋亡及其作用机制的研究  

Conjugated linoleic acid isomers induced apoptosis of human breast cancer cell line MCF-7

作　　者：袁贤琳[1,2] 陈青[1] 杨湘玲[1] 钟翎[1] 

机构地区：[1]中山大学药学院微生物与生化制药实验室,广州510006 [2]广州市中医医院药剂科,广州510130

出　　处：《肿瘤》2009年第6期537-543,共7页Tumor

基　　金：国家自然科学基金资助项目(编号:30873457);广东省科技计划项目(编号:2008A060202010)

摘　　要：目的:研究2种共轭亚油酸(conjugated linoleic acid,CLA)单体——顺9,反11-CLA(cis 9,trans11-CLA,c9,t11-CLA)和反10,顺12-CLA(trans10,cis12-CLA,t10,c12-CLA)诱导乳腺癌细胞MCF-7凋亡及其作用机制。方法:采用MTT法检测CLA对MCF-7细胞的生长抑制作用,锥虫蓝染色绘制CLA作用后MCF-7细胞的生长曲线;荧光显微镜观察及FCM检测MCF-7细胞的凋亡和细胞周期的改变;RT-PCR和Western印迹法检测MCF-7细胞PPARγ、Bcl-xL和Bcl-xS mRNA以及PPARγ、Bcl-2、Bax和caspase-3的蛋白表达。结果:2种CLA单体均可抑制MCF-7细胞增殖并诱导细胞凋亡,与对照组相比差异有统计学意义(P<0.05);RT-PCR和Western印迹法检测结果显示,2种CLA单体均可以提高PPARγ、Bcl-xS mRNA和PPARγ、Bax、caspase-3蛋白的表达,降低Bcl-xL mRNA和Bcl-2蛋白的表达,与对照组比较差异有统计学意义(P<0.05);且2种CLA单体对PPARγ与凋亡相关蛋白Bax、Bcl-2和caspase-3的表达影响呈剂量和时间依赖性及同步相关性。结论:c9,t11-CLA和t10,c12-CLA对乳腺癌MCF-7细胞具有抑制生长和促凋亡的作用,CLA可能作为PPARγ的配体通过激活PPARγ-Bcl-2-caspase-3细胞凋亡信号通路而实现抑制肿瘤细胞生长的作用。Objective：To study the effects of two kinds of conjugated linoleie acid （ CLA）, cis 9, traMs 11-CLA and traMs 10, cis 12-CLA in inducing apoptosis of breast cancer MCF-7 cells and the action mechanism. Methods：The inhibitory effect of CLA on proliferation of MCF-7 cells was assessed by MTY assay. Trypan blue staining was used to investigate the growth of MCF-7 cells. Hoechst 33342 fluorescence microscopy and flow cytometry were used to detect the apoptosis of MCF-7 cells and cell cycle distribution. The nlRNA transcriptions of PPARγ（peroxisome proliferators activated receptor γ） , Bcl-xL, and Bcl-xS were determined by RT-PCR. The protein expressions of PPARγ, Bcl-2, Bax, and caspase-3 were detected by Western blot. Results：Two kinds of CLA isomers could inhibit cell proliferation and induce apoptosis. The difference was significant compared with control group （ P 〈 0.05 ）. c 9, tl 1-CLA and t10, c12-CLA increased the PPARγ and Bcl-xS mRNA transcription and PPARγ, Bax, and caspase-3 protein expression （P 〈 0.05） and decreased Bcl-xL mRNA and Bcl-2 protein expressions. The difference was significant compared with control group （P 〈 0.05）. The effects of c 9, t11-CLA and t10, c12-CLA on the expression of PPARγ and apoptosis-related proteins Bax, Bcl-2, and caspase-3 were in dose-and time-dependent manners and had concurrent correlations. Conclusion： c 9, t11-CLA and t10, c12-CLA could inhibit MCF-7 cells proliferation and induce apoptosis. CLA may serve as a PPARγ ligand and exert its anti-tumor effects by activating PPARγ-Bcl-2-caspase-3 apoptotic signaling pathway.

关 键 词：乳腺肿瘤 细胞凋亡 细胞周期 共轭亚油酸单体 细胞 MCF-7 

分 类 号：R737.9[医药卫生—肿瘤]