GRP78在肺腺癌细胞顺铂耐药中的作用

The Role of GRP78 on the Resistance to Cisplatin in SPCA-1 Cell Line

背景与目的糖调节蛋白78(GRP78)在肺癌细胞中表达增高并与其对化疗药物VP-16的耐药性有关,而GRP78的表达与其对化疗药物顺铂的耐药性是否相关,研究较少。本研究旨在通过检测GRP78在人肺腺癌细胞SPCA-1中的表达及顺铂作用后的细胞生存率,研究GRP78在肺腺癌细胞顺铂耐药中的作用。方法依据是否应用诱导剂A23187将细胞分为实验组和对照组,采用RT-PCR、Western blot方法检测各组细胞中GRP78在核酸和蛋白水平的表达,利用MTT法测定细胞在顺铂作用下的生存率,分析GRP78在SPCA-1细胞顺铂耐药中的作用。结果A23187可以明显诱导SPCA-1细胞中GRP78在核酸和蛋白水平的表达,且其表达水平与A23187具有一定的浓度依赖性,MTT检测显示:实验组细胞生存率明显低于对照组,亦呈一定的A23187浓度依赖性。结论在人肺腺癌细胞SPCA-1中,诱导剂A23187可以诱导GRP78核酸和蛋白水平的表达,其表达与肺癌细胞在顺铂作用下的生存率呈负相关,表明GRP78可提高SPCA-1细胞对顺铂的敏感性,与肺癌细胞化疗耐药有一定的相关性。

Background and objective The expression levels ofghicose-regulated protein 78 （GRP78） were elevated and correlated with resistance to chemotherapy drug VP-16 in lung cancer cells. However, little is known about the relationship between its expression and resistance to cisplatin in lung cancer cells. The aim of this study was to investigate the expression of GRP78 under the induction ofA23187 and its significance in the resistance to anti-tumor drugs cisplatin in a human lung cancer SPCA-1 cell line. Methods RT-PCR and Western blot were used to analyze the expression of GRP78 at mRNA and protein levels in SPCA- 1 cell line induced by A23187 at different concentrations （0,1, 2, 4, 6 8M）. MTT was used to determine the effect of cisplation on cell survival. Results The expressions of GRP78 at both mRNA and protein levels were increased obviously in SPCA-1 cell line induced byA23187, with a manner of dose-dependent ofA23187 to a great degree; MTT assay showed that the cell survival rate of the A23187-induced group decreased significantly compare to the control group, also with a concentrationdependent manner ofA23187. Conclusion The expression of GRP78 at both mRNA and protein levels were increased obviously in SPCA- 1 cell line induced by A23187. The enhancement of GRP78 showed a negative correlation with the cell survival rate treated by cisplatin. All these indicated that overexpression of GRP78 can enhance the sensitivity to cisplatin and there is correlation between the expression of GRP78 and resistance to cisplatin of human lung cancer SPCA-1 cell line.