摘要
目的 探讨胆固醇合成抑制剂洛伐他汀对MCF 7乳腺癌细胞RhoGTPases活性及细胞骨架形成的影响。方法 采用逆转录 PCR检测Rho、Rac2和RhoGDImRNA的表达水平 ,放射自显影方法分析RhoGTPases活性 ,激光共聚焦和透射电镜观察微丝和中间丝的形成。结果 4～ 16μmol L的LOV处理MCF 7细胞 48～ 72h后 ,RhoAmRNA表达均无明显变化 ,而Rac2mRNA和RhoGDImRNA随洛伐他汀的处理 ,各剂量组mRNA表达均呈增加趋势 ;放射自显影结果发现 ,LOV处理细胞 72h后 ,各处理组RhoGTPases结合的GTP量明显低于对照组 ;此外 ,LOV能明显促进MCF 7细胞微丝和中间丝的形成 ,该作用有一定剂量 效应和时间依赖关系。结论 洛伐他汀处理MCF 7乳腺癌细胞 ,因妨碍RhoGTPases蛋白转录后的香叶酯焦磷酸活化修饰而导致RhoGTPases活性降低 ,但它却能明显促进MCF 7细胞骨架的形成。
Objective To investigate the effects of lovastatin (LOV) on Rho GTPases activity and cytoskeleton organization in MCF 7 cells. Methods Expression levels of RhoA, Rac2, and RhoGDI mRNA were determined by RT PCR analysis. GTP binding activity of Rho GTPases was detected by autoradiography. Microfilament and intermediate filament reformations were observed by confocal laser microscopy and electron microscopy. Results After treatment of MCF 7 cells with 4-16 μmol/L LOV for 48-72 h, the expression levels of Rac2 mRNA and RhoGDI mRNA were up regulated, but the binding abilities of Rho GTPases and GTP decreased AT 72 h after treatment. There was no obvious change in the expression of RhoA mRNA. In addition, LOV obviously accelerated the reformation of microfilament and intermediate filament in dose and time dependent manners in MCF 7 cells. Conclusion LOV can inhibit the activation of Rho GTPases through blocking the post translational geranylgeranylpyrophosphate of Rho GTPases, but can obviously promote the cytoskeleton reorganization in MCF 7 cells.
出处
《第三军医大学学报》
CAS
CSCD
北大核心
2004年第3期196-200,共5页
Journal of Third Military Medical University
基金
国家自然科学基金资助项目 ( 30 2 7112 8)~~
