ERCC2诱导表达在人脑胶质瘤细胞对BCNU耐药中的作用

目的：探讨BCNU诱导ERCC2表达在胶质瘤细胞耐药中的作用。方法：选用ERCC2基础表达在蛋白水平相同，而mRNA水平不同的2株人脑胶质瘤细胞T98-G和SK-MG-4（在mRNA水平，T98-G比SK-MG-4高25倍），在体外培养时用BCNU处理，随后采用Western Blot测定肿瘤细胞的ERCC2蛋白水平变化。结果：对BCNU耐药的T98-G在BCNU处理后6h，ERCC2蛋白水平上升6倍，随后逐渐下降，48h回复到基础水平。而对BCNU敏感的SK-MG-4，BCNU处理后ERCC2蛋白水平没有增加。结论：本研究提示，mRNA基础水平与胶质瘤耐药密切相关，在mRNA基础水平较高的肿瘤细胞，BCNU能诱导ERCC2蛋白表达，并直接与肿瘤耐药相关。

Induced ERCC2 expression Vis-a-Vis BCNU resistance in human glioma cell lines

Objective To order to further clarify the rule of ERCC2 to CENU resistance in human gliomas. Methods We treated two cell lines T98 G and SK MG 4 with BCNU, in which the basal ERCC2 protein levels are similar but mRNA levels are different (Twenty five folds higher in T98 G than that in SK MG 4). The ERCC2 protein levels were measured at different time points after BCNU treatment. Results Six hours following the treatment, ERCC2 protein level was increased 6 folds and then gradually returned to basal level till 48 hours in the resistant cell line T98 G. While there was no significant changes of the ERCC2 protein levels in the sensitive cell line SK MG 4. Conclusions Our present results suggest that tumor cells with high ERCC2 mRNA may be more resistant to BCNU even though their baseline ERCC2 protein levels are low. BCNU treatment may induce ERCC2 protein expression in cell lines with high ERCC2 mRNA and thus contribute to resistance to the drug of chemotherapy.