MGMT反义RNA对人脑胶质瘤细胞系U251／BCNU耐药性逆转的研究

为逆转胶质瘤的耐药性,模拟临床亚硝基脲类药物的用药程序,在体外建立由MGMT介导的人脑胶质瘤耐药细胞系U251／BCNU,并进行细胞耐药性检测和细胞中MGMTmRNA表达的分析;观察MGMT反义RNA对U251／BCNU细胞MGMT表达的调节作用及对U251／BCNU细胞BCNU敏感性的影响。经过5次用药过程,首次在体外成功地建立了对BCNU具有稳定抗性的U251／BCNU,其对BCNU的耐受程度约为U251的17倍;RT－PCR结果显示,U251／BCNU细胞有MGMTmRNA的表达。MGMT反义RNA的表达载体pLaMT5SN和pLaMTSN能够在一定程度上降低U251／BCNU细胞中MGMTmRNA的表达水平,提高其对BCNU的敏感性。认为MGMT反义RNA能够在一定程度上抑制MGTMT的表达水平,提高肿瘤细胞对亚硝基脲类药物的敏感性。

Reveral of drug resistance of human glioma cell line U251/BCNU by MGMT antisense RNA

To reverse the drug resistance of glioma by antisense RNA. Simulating the clinical way of nitrosoureas,a BCNU resistant human glioma subline U251/BCNU was established.The resistance factor and the expression of MGMT mRNA of U251/BCNU were detected.The effect of MGMT antisense RNA on MGMTmRNA expression by RT PCR and the sensitivity to BCNU were observed by RT PCR an MTT assay of U251/BCNU.Result showed that pLaMT5SN and pLaMTSN could down regulated the expression of MGMTmRNA to a certain extent. The sensitivity of aMT5U and aMTU cells to BCNU were 7 and 2 fold higher than that of U251/BCNU cells by MTT assay,This suggest that MGMT antisense RNA could down regulated the expression of MGMT, and enhance the sensitivity of tumor cells to nitrosoureas. Antisense RNA is a effective way to reverse the drug resistance of gliomas, and has prospects for clinical application in the future.