替莫唑胺诱导大鼠脑胶质瘤C6细胞caspase非依赖的程序性死亡

摘要

Objective To investigate programmed cell death induced by temozolomide in rat glioma C6 cell line. Methods Rat glioma C6 cell line was treated by temozolomide at different concentrations and for different time lengths. MTT assay was used to evaluate the cell inhibition rate to determine the optimal exposure time and concentration. After the exposure to 400μg/ml temozolomide for 24 h, the cells were observed for programmed cell death using HE staining, Hochest and Tunnel assay, Western blotting, and immunohistochemistry. Results MTT, HE staining, and Hochest and Tunnel assay all showed temozolomide-induced apoptosis in rat glioma C6 cell line. Western blotting and immunohistochemistry revealed up-regulation of Bax and down-regulation of Bcl-2 expression in the exposed cells, where the expressions of caspases 3, 8, 9, and 12 remained unchanged. Conclusion Temozolomide induces apoptosis in rat glioma C6 cell line through a caspase-independent pathway.%目的：观察替莫唑胺对大鼠脑胶质瘤C6细胞程序性死亡的诱导效应，并探讨可能的分子机制。方法观察不同浓度替莫唑胺在不同时间点处理大鼠脑胶质瘤大鼠脑胶质瘤C6细胞系，MTT法观察抑制率并筛选出最优的作用时间和作用浓度。应用400μg/ml替莫唑胺处理细胞24 h，通过HE染色、Hochest、Western blot、Tunnel、免疫组化观察替莫唑胺对大鼠脑胶质瘤C6细胞系的程序性死亡的诱导效应。结果 MTT法、HE染色、Hochest和Tunnel结果显示替莫唑胺对大鼠脑胶质瘤C6细胞具有凋亡诱导效应；免疫组化和Western blot结果显示促凋亡蛋白Bax表达水平上调，凋亡抑制蛋白Bcl-2表达的下调。未发现主要的caspase蛋白的表达变化。结论替莫唑胺对脑胶质瘤C6细胞具有凋亡诱导效应，而这种效应可能是通过caspase非依赖途径完成的。