Molecular pro filing of genes specifically up-regulated during

在寻找基因稳定上调，在促进阶段的致癌作用，抑制PCR消减杂交和以下北方印迹筛选进行了使用苯巴比妥（PB）促进模型的基础上，中期肝脏生物测定。在用二乙基亚硝胺（DEN）开始两周后，大鼠被给予PB长达64周。为了进行比较，还包括在促进阶段在饲料中给予乙炔基乙醇（EE）或丁基羟基甲苯（BHT）的动物。在第3周对大鼠进行部分肝切除术（PH）。此外，在促进的第8周检查PB的剂量依赖性和对代表性非遗传毒性致癌物的反应性，而没有DEN启动。通过从单独DEN+PH的基础表达中减去，在PB处理的第10天从肝脏中上调的基因群体中分离出总共67个不同基因的片段。通过北方杂交筛选出48个可检测到信号的基因，其中16个基因表达上调。 ...更多信息 e促进第8周时的肝脏，与未促进的肝脏的基础表达相比，PB和EE处理常见。这些基因中的大多数在BHT处理的第8周也被上调，并且在DEN（-）、PH（-）未处理的大鼠肝脏中也组成性表达。在PB和EE促进共同上调的基因中，并且在未启动的肝脏中对非遗传毒性致癌物无反应，以下6个基因在第64周时在PB促进的肝细胞癌中显示过表达;普遍表达的哺乳动物ABC半转运蛋白、载脂蛋白A4（APOA 4）、核受体结合因子-2，CD 81、假设蛋白（HSPC 014）和一个未鉴定的基因。这些基因可能是筛选非遗传毒性肝癌的生物标志物的候选人通过分析两阶段致癌模型。此外，在硫代乙酰胺促进的肝脏中，观察到特异于GST-P阳性病灶的APOA 4 mRNA信号的原位定位。虽然APOA 4在肝癌发生中的作用还需要进一步研究，但APOA 4可能与肿瘤病变的形成有关。少

In search of genes steadily up-regulated during the promotion stage in carcinogenesis, suppression PCR subtractive hybridization and following Northern blot screening were performed using a phenobarbital (PB)-promotion model based on a medium-term liver bioassay. Two weeks after an initiation with diethylnitrosamine (DEN), rats were given PB for up to 64 weeks. For comparison, animals given ethinylestradiol (EE) or butylated hydroxytoluene (BHT) in the diet at promotion stage were also included. Rats were subjected to partial hepatectomy (PH) at week 3.In addition, dose-dependence of PB at week 8 of promotion and responsiveness to representative non-genotoxic carcinogens without DEN-initiation were examined. Fragments of a total of 67 different genes were isolated from the up-regulated gene population in the liver at day 10 of PB-treatment by subtracting from basal expression of DEN+PH alone. By Northern blot screening for signal-detectable 48 genes, 16 genes showed up-regulation in th … More e livers at week 8 of promotion, common to the PB-and EE-treatments as compared to the basal expression of unpromoted liver. The majority of these genes were also up-regulated at week 8 by BHT-treatment, and were also constitutively expressed in the DEN(-), PH(-)-untreated rat livers. Among the up-regulated genes common to the PB- and EE-promotion, and not responding to the non-genotoxic carcinogens in uninitiated liver, the following 6 genes showed overexpression in PBpromoted hepatocellular carcinomas at week 64 ; ubiquitously expressed mammalian ABC half transporter, apolipoprotein A4 (APOA4), nuclear receptor binding factor-2, CD81, hypothetical protein (HSPC014), and one unidentified gene. These genes might be candidates for biomarkers in screening of non-genotoxic hepatocarcinogens by analysis in two-stage carcinogenesis models. In addition, in situ localization of APOA4mRNA-signal was observed specific to GST-P-positive foci in the thioacetamide-promoted livers. Although further study is required on the role in the hepatocarcinogenesis, APOA4 may link to the formation of neoplastic lesions. Less