甲基叔丁基醚对原癌基因和功能基因表达的影响

Effect of methyl tertiary butyl ether on the expression of proto oncogenes and function genes

甲基叔丁基醚（ＭＴＢＥ）是一种新型的汽油添加剂，被用来提高汽油燃烧效率，减少汽车尾气中有害物质的排放。ＭＴＢＥ具有一定的动物致癌性，但其机制目前并不清楚。本研究采用免疫组织化学方法，检测了ＭＴＢＥ对体外培养的ＮＩＨ３Ｔ３细胞中ｃ－ｍｙｃ和ｐ２１蛋白表达的影响；采用点杂交方法，从ＲＮＡ水平检测了ＭＴＢＥ亚慢性染毒大鼠肝组织中原癌基因ｃ－ｍｙｃ基因和功能基因ＧＳＴ－Ｐ基因的表达情况。免疫组化结果显示，ＭＴＢＥ可诱导ｃ－ｍｙｃ基因的高表达，对ｐ２１蛋白的表达未见明显影响。点杂交结果显示，ＭＴＢＥ可明显诱导大鼠肝组织中ｃ－ｍｙｃ基因的高表达，而对ＧＳＴ－Ｐ基因的表达未见明显影响。上述结果提示，ＭＴＢＥ可诱导细胞中ｃ－ｍｙｃ基因表达活性增高，可能是其动物致癌性的机制之一。

Methyl tertiary butyl ether (MTBE) is a new gasoline additive, which is used to increase the combustion of gasoline and to reduce the emission of harmful exhausts from automobile. The mechanism for the carcinogenesis of MTBE in animals is not clear.Immunohistochemistry method was used to detect the effect of MTBE on the expression of c myc and p21 proteins in NIH 3T 3 cells. Dot hybridization method was used to explore the expression of c myc gene and GST P(glutathione S transferase P) gene in the of MTBE treated rats.The results showed that MTBE could enhance the expression of c myc protein,but had no effect on p21 protein. MTBE could induce high expression of c myc gene,and had no effect on the expression of GST P gene.These results suggest that the high expression of c myc gene induced by MTBE might be one of the mechanisms of its carcinogenicity in animal.