bcl-2、c-myc基因表达在去甲二氢愈创木酸诱导人恶性胶质瘤细胞凋亡中的意义

Significance of bcl-2 and c-myc gene expression in nordihydroguaiaretic acid-induced apoptosis of a human malignant glioma cell line

目的 观察bcl 2、c myc在去甲二氢愈创木酸 (NDGA)诱导恶性胶质瘤细胞系SHG 44细胞凋亡中的变化及意义。方法 利用光镜和电镜观察及TUNEL法检测培养细胞凋亡的情况 ,用免疫组织化学、原位杂交和图像分析等方法检测bcl 2、c myc基因mRNA和蛋白的表达水平。结果 ①一定浓度的NDGA处理SHG 44细胞 1 2～ 96h ,均可诱导SHG 44细胞发生凋亡 ,且随着作用时间的延长 ,凋亡细胞数增加越明显 ;②经NDGA处理细胞后 ,出现SHG 44细胞bcl 2、c myc蛋白表达水平降低 ,且随着作用时间的延长 ,这种趋势更加明显 ,与细胞凋亡的发生密切相关 ;③原位杂交结果显示 ,NDGA处理细胞不同时间后 ,出现SHG 44细胞bcl 2、c myc基因mRNA的表达水平降低 ,结果与免疫组化检测一致。结论 NDGA诱导SHG 44细胞的凋亡可能与其下调bcl 2、c myc基因的表达有关 。

Objective To investigate the changes and their significance of bcl 2 and c myc in nordihydroguaiaretic acid (NDGA) induced apoptosis of human malignant glioma cell line SHG 44. Methods The apoptosis of SHG 44 cells was observed with light and electron microscopy and TUNEL method. The expression of bcl 2 and c myc gene was measured with immunohistochemistry, in situ hybridization and image analysis. Results ① The SHG 44 cell apoptosis was induced by NDGA at a concentration lower than 200 μmol/L in a time dependent manner. ② The expressions of bcl 2 and c myc gene in SHG 44 cells were decreased after the treatment of 100 μmol/L NDGA with the elapse of time, indicating a close association with cell apoptosis. ③ The expressions of bcl 2 and c myc mRNA in SHG 44 cells were decreased after the treatment with 100μmol/L NDGA, which was apparently consistent with the immunohistochemical results. Conclusion The NDGA induced apoptosis in human malignant glioma cells might be related with the down regulated expressions of bcl 2 and c myc gene. The exact mechanism needs further research.