Yoshida D, Hoshino S, Shimura T, Takahashi H, Teramoto A
Department of Neurosurgery, Nippon Medical School, Tokyo, Japan.
J Neurooncol. 2000 Apr;47(2):133-40. doi: 10.1023/a:1006393705560.
The drug effect of estramustine phosphate (EMP), an anti-microtubule agent on human glioma cells has been studied with the focus being mainly its cytotoxity or its targeting of organelles. However, the pharmacological knowledge of estramustine with respect to its cytotoxity and mechanism is limited. To acquire such knowledge, the present study investigates the ability of EMP to induce apoptosis in a human malignant glioma cell line. Transmission electron microscope (TEM) images were examined to monitor periodic changes. Agarose gel electrophoresis was also examined. Cellular DNA fragmentation ELISA was performed to investigate the DNA fragmentation rates and an MTT assay was studied to evaluate the ID50. A TEM study revealed condensing and fragmentation of the chromatin. Laddering of the bands was observed in all EMP exposure groups in agarose gel electrophoresis. DNA fragmentation in all EMP groups began at 0.5 h following an exposure with EMP and increased in a dose- and time-dependent manner as revealed by DNA ELISA fragmentation. ID50 at 24 h was 5.0 microM according to the MTT assay, a value close to 4.8 microM of ID50 was revealed by the DNA fragmentation assay. None of the above mentioned changes was observed in the control group. These results indicated that EMP caused a drug-induced apoptosis in the human malignant glioma cell line, U87MG.
磷酸雌莫司汀（EMP）作为一种抗微管药物对人胶质瘤细胞的药物作用已被研究，重点主要在于其细胞毒性或对细胞器的靶向作用。然而，关于雌莫司汀细胞毒性及其机制的药理学知识有限。为了获得此类知识，本研究调查了EMP诱导人恶性胶质瘤细胞系凋亡的能力。通过检查透射电子显微镜（TEM）图像来监测周期性变化。还检查了琼脂糖凝胶电泳。进行细胞DNA片段化ELISA以研究DNA片段化率，并进行MTT试验以评估ID50。TEM研究显示染色质凝聚和碎片化。在琼脂糖凝胶电泳的所有EMP暴露组中均观察到条带形成梯状。如DNA ELISA片段化所示，所有EMP组中的DNA片段化在暴露于EMP后0.5小时开始，并呈剂量和时间依赖性增加。根据MTT试验，24小时的ID50为5.0微摩尔，DNA片段化试验显示ID50值接近4.8微摩尔。在对照组中未观察到上述任何变化。这些结果表明，EMP在人恶性胶质瘤细胞系U87MG中引起了药物诱导的凋亡。
