食管癌放射抗拒细胞P-gp和GST-π表达的研究

Study of P-gp and GST-π expression on human radioresistance esophageal carcinoma cells

目的研究食管癌放射抗拒细胞多药耐药基因的表达。方法以食管癌EC9706细胞为研究对象,采用长期、间隔、γ射线照射的方法建立放射抗拒的食管癌EC9706细胞系EC9706-R,MTT法测定EC9706-R的耐药指数,免疫细胞化学法和RT-PCR法分别测定P-gp、GST-π的蛋白和mRNA的表达。结果EC9706-R细胞耐药指数是EC9706细胞的1.24倍,P-gp和GST-π的蛋白均有表达,mRNA表达比EC9706细胞高。结论诱导建立的食管癌放射抗拒细胞EC9706-R的化疗耐药性有所增高,原因多为放疗增加了P-gp和GST-π的表达。

Objective To investigate the expression of MDR gene on human radioresistance esophageal carcinoma cells. Methods A long-term,intermittent, γ radiation was added into the culture cells to induce human radioresistance esophageal carcinoma cells named EC9706-R; MTT assay was used to detect the RI of EC9706-R. Immunocytochemistry and RT-PCR were used to evalue the expression of P-gp and GST-π. Results The human radioresistance esophageal carcinoma cells EC9706-R, compared to EC9706 cells,the reverse index （RI） was 1.24 times. Overexpression of P-gp and GST-πin mRNA level was found in the EC9706-R. Conclusion The treatment of human esophageal carcinoma cells with a long-term,intermittent,γ radiation could induce radioresistance esophageal carcinoma cells. The result suggests radiotherapy can enhance the expression of P-gp and GST-π,which induce high chemoresistance of EC9706-R.