【摘要】 背景与目的:碱性鞘磷脂酶(alk-SMase)是鞘磷脂(SM)新陈代谢和发挥抑制结肠癌作用的关键酶。通过体外实验探讨SM的水解产物的神经酰胺(Cer)和鞘氨醇(Sph)对人结肠癌细胞HT-29中alk-SMase表达的影响。材料与方法:分别用12.5、25、50μmol/L的C2-Cer和Sph处理HT-29细胞12、24、48 h后,分别用Western blot法和RT-PCR检测细胞中alk-SMase的蛋白水平和mRNA表达水平的变化。实验并设DMSO溶剂对照组。结果:C2-Cer和Sph作用HT-29细胞后,其alk-SMase蛋白及其mRNA的表达下调。结论:Cer和Sph对HT-29细胞中alk-SMase的表达具有负反馈调节作用。更多还原

【Abstract】 BACKGROUND AND AIM: Alkaline sphingomyelinase(alk-SMase) is the key enzyme of sphingomyelin(SM) metabolism,and an inhibitor of colon cancer.Through vitro experiments,we examined the alk-SMase expression in human colon cancer HT-29 cells,which produced the hydrolysis products of SM,ceramide(Cer) and sphingosine(Sph).MATERIALS AND METHODS: After treatment with 12.5,25 and 50 μmol/L of C2-Cer and Sph for 12,24 and 48 hours,we tested the alk-SMase mRNA and protein expressions in HT-29 cells.DMSO was the control.RESULTS: Compared with the control group,the alk-SMase expression of protein and mRNA level was reduced by C2-Cer and Sph in HT-29 cells,With a clear dose-response relationship. CONCLUSION: Cer and Sph exerted negative feedback on alk-SMase.Cer and Sph might have induced apoptosis directly in colon cancer cells,rather than through hydrolysis of SM.更多还原