高强度超声对人乳腺癌细胞中COX-2mRNA表达的影响

Effect of hi2h intensity ultrasound on COX-2 mRNA expression in human breast cancer cells

目的探讨高强度超声对环氧化酶一2（COX一2）mRNA的表达及其影响乳腺癌MDA—MB-231细胞凋亡的作用机制。方法用高强度超声（50w／cm^2）干预体外培养的人乳腺癌MDA—MB-231细胞。RT—PCR检测干预前后MDA．MB一231的COX．2mRNA的相对水平，透射电镜观察细胞超微结构。结果随着高强度超声干预时间的增加，COX-2mRNA相对水平逐渐下调，电镜下可见明显的凋亡小体。干预时间增加到30s，部分细胞出现死亡的形态学改变。结论高强度超声干预在一定作用时间内促进乳腺癌MDA-MB一231细胞COX一2依赖性的细胞凋亡。

Objective To study the mechanism of high intensity ultrasound （HIU） on COX-2 mRNA expression and apoptosis in breast cancer cell line MDA-MB-231 cells. Methods Human breast cancer cells MDA-MB-231 in vitro were exposed in HIU （50 w/em2）. RT-PCR was performed to detect the level of COX-2 mRNA before and after exposure. The uhrastruetural changes in apoptotie cells were examined by transmission e- lectron microscopy. Results The relative level of COX-2 mRNA decreased gradually along with the increase of exposure time and apoptotic bodies in MDA-MB-231 cells considerably increased under electron microscope. When exposure time was increased to 30 seconds, a few cells died. Conclusion HIU promotes apoptosis of breast cancer MDA-MB-231 cells in a COX-2 mRNA d^nended way.