Role of Oncogene and Cytochrome P450 in Carcinogenesis of Gynecologic carcinoma

大多数致癌物是由细胞色素P450(Cyps)激活的，靶细胞内的这些酶与癌症的易感性密切相关。由于肝外细胞色素P450的水平通常要低得多，因此很难评估肝外组织中细胞色素P450的存在和作用。在本研究中，我们改进了逆转录聚合酶链式反应(RT-PCR)来检测人子宫内膜中CyP2E1mRNA的含量。从人子宫内膜中提取总RNA，在含有CyP2E1和β-肌动蛋白两对引物的同一试管中进行逆转录和共扩增。CyP2E1和β-肌动蛋白的扩增产物分别为298bp和600bp。限制性内切酶MboI将这两种产物酶切至DNA片段大小预测的大小，证明这两种扩增产物都是特异的，并且人子宫内膜中存在CyP2E1mRNA。细胞色素P4501A1m RNA也可检测到，但检测不清。在反应混合物中加入[Alpha-^&lt；32&gt；P]dCTP，可以量化与β-肌动蛋白产物相比较的CyP2E1PCR产物的相对产量。在25个循环扩增的时间点，可以计算出CyP2E1PCR产物与β-肌动蛋白PCR产物的产率之比。这一比值与血清雌二醇水平呈正相关(P=0.654.0 5，P<0.0 5)，但与血清孕酮水平无相关性。

Most carcinogens are bioactivated by cytochrome P450(CYPs) and these enzymes within target cells are closely related to susceptibility to cancer. Since extrahepatic CYPs are typically at much lower levels, the existence and the role of CYP in extrahepatic tissues have been difficult to assess. In this study, we modified the reverse transcriprtase-ploymerase chain reaction (RT-PCR) to evaluate the quantities of CYP 2E1 mRNA in human endometrium. Total RNA from human endometrium was reverse transcribed and coamplified by PCR in the same tube containing both primer pairs of CYP 2E1 and beta-actin. The CYP 2E1 and beta-actin PCR products were 298 bp and 600 bp, respectively. The restriction enzyme mboi digested these two products to the predicted size for DNA fragments, demonstrating that both PCR products were specific and CYP 2E1 mRNA exists in human endometrium. CYP 1A1 mRNA was also examined, m but could not be detected clearly. Adding [alpha-^<32>P]dCTP to reaction mixture made it possible to quantify the relative yield of the CYP 2E1 PCR product in comparison with the beta-actin product. The ratio of the yield of the CYP 2E1 PCR product comparison with the beta-actin PCR product could be calculated at a point of 25 cycles of amplification. This ratio and serum estradiol levels were correlated positively (gamma=0.654, P<0.05), but not relationship to serum progesterone Levels was observed.