高三尖杉酯碱诱导K562细胞的编程性细胞死亡

APOPTOSIS INDUCED BY HOMO-HARRINGTONINE IN K562 CELLS

目的探讨高三尖杉酯碱诱导人白血病细胞系K562细胞编程性细胞死亡的作用。方法将不同浓度高三尖杉酯碱加入K562细胞培养体系，采用光镜、电镜和电泳方法观察药物处理后K562细胞的编程性细胞死亡。结果高三尖杉酯碱（2μg／ml～200μg／ml）能明显诱导K562细胞的编程性细胞死亡，药物处理后24h和36h时死亡细胞所占比例较高。光镜下该类细胞体积变小，核染色质凝聚，核碎裂。电镜下见该类细胞核膜完整，核染色质向边缘集中，形成致密染色质块。DNA电泳示小片段DNA明显增加，微呈梯形外观。结论高三尖杉酯碱能诱导人白血病K562细胞系的编程性细胞死亡。

To examine the effect of homo-harringtonine on programmed cell death in human leukemia K562cells. METHODS Apoptosis is to be studied after K562 cells exposed to 2-200pg/ml concentrations of homo-harringtonine for 6 to 48 hours by DNA eletrophoresis, light and electron microscopic examination. RESULTS Afterexposed to drugs for 24 or 36 hours. the percentage of apoptotic cells was increased significantly. The K562 cellsundergoing apoptosis displayed the following morphological features: reduced cell volume, condenced chromatin inthe nucleus. formation of internucleosomal DNA fragmentation. and finally, loss of membrane integrity as well asgeneration of apoptotic bodies. By agarose gel analysis, durg-induced DNA fragmentation showed the characteristic pattern of internucleosomal ladder. CONCLUSION Our results demonstrate that the K562 cell killing effect ofhomo-harringtonine is medicated. at least in part, by the induction of apoptosis.