摘要
目的探讨胃癌组织中DNA甲基化调控机制对runt相关转录因子3（Runx3）基因表达的影响。方法采用逆转录聚合酶链反应（RT-PCR）法检测70例胃癌组织及其配对的正常胃黏膜组织中Runx3mRNA表达，Westenblot法检测Runx3蛋白表达，甲基化特异性PCR（MSP）法检测Runx3基因启动子的甲基化状态；应用RT-PCR法检测DNA甲基转移酶1（Dnmtl）mRNA表达，分析Runx3基因甲基化与Dnmt1 mRNA表达之间的相关性。结果胃癌组织中Runx3mRNA表达（0．5740±0．3580）明显低于其配对的正常胃黏膜组织（1．7250±0．4080，P〈0．05），胃癌组织Runx3蛋白表达亦明显低于其配对的正常胃黏膜组织（P〈0．05）。在Runx3 mRNA表达下调的56例胃癌组织中，有28例（50．0％）呈启动子高甲基化状态。胃癌组织中，Runx3甲基化阳性者的Dnmt1 mRNA表达量明显高于Runx3甲基化阴性者（P〈0．05），Runx3基因启动子甲基化与Dnmt1转录表达呈正相关（r=0．64，P〈0．05）。结论Runx3基因启动子高甲基化是其基因表达下调的原因之一，可能参与胃癌的发生发展；Dnmt1高表达可能影响Runx3启动子区域甲基化改变。
Objective This study was designed to clarify the significance of DNA methylation in the expression of runt-related transcription factor 3 （ Runx3 ） gene. Methods Reverse transcription-PCR （ RT- PCR） was used to measure the expression level of Runx3 mRNA in paired samples of primary gastric cancer and corresponding non-cancerous gastric mucosa, taken from surgical specimens of 70 gastric cancer patients. Western blot was used to detect the protein expression level of Runx3 gene. The promoter methylation status of Runx3 gene was detected by methylation specific PCR （MSP）. Furthermore, RT-PCR was used to mesure the expression of DNA methyltransferase 1 （ Dnmt1 ） mRNA . The correlation of Runx3 expression and methylation with Dnmtl mRNA expression was analyzed. Results The mRNA expression level of Runx3 gene was significantly lower in gastric cancer than that in the matched normal gastric mucosa （0.5740 ±0. 3580 vs. 1. 7250 ± 0. 4080, P 〈 0.05 ）, and the Runx3 protein expression level in gastric cancer was also significantly lower than that in the matched normal gastric mucosa （ P 〈 0.05 ）. Promoter hypermethylation of Runx3 gene was detected in 50.0% （28/56） of the gastric cancer samples, which resulted in a reduced expression of Runx3 mRNA. It was found that the mRNA expression level of Dnmtl gene was significantly higher in the gastric cancer tissues with methylated Runx3 gene than that in the ones without. There was a significant correlation of Runx3 gene methylation with increased expression of Dnmtl mRNA （ r = 0.64,P 〈 0.05 ）. Conclusion The promoter hypermethylation may be one of the predominant inactivation mechanisms of the runt-related transcription factor 3 gene, and may be associated with carcinogenesis of human gastric cancer. Reduced Runx3 expression in gastric cancer may be partially correlated with a high level of DNA methyhransferase 1.
出处
《中华肿瘤杂志》
CAS
CSCD
北大核心
2008年第5期361-364,共4页
Chinese Journal of Oncology
基金
江苏省医学重点人才资助项目（RC2007076） 志谢 上海交通大学附属仁济医院消化病研究所房静远教授为本实验提供帮助
朱红音、陆嵘、王霞等在实验操作等方面给予支持
