叶酸对健康人外周血单个核细胞肿瘤相关基因甲基化状态的影响  

The effect of folic acid on DNA methylation of tumor-related genes in healthy human peripheral blood mononuclear cells

作　　者：叶婷[1] 傅琳娜[1] 李文英[1] 陈萦晅[1] 房静远[1] 

机构地区：[1]上海交通大学医学院附属仁济医院消化科上海市消化疾病研究所,200001

出　　处：《中华消化杂志》2011年第5期312-317,共6页Chinese Journal of Digestion

基　　金：上海市浦江人才计划资助项目（10PJ1407200）;上海市科技创新行动计划资助项目（09DZ1950101）国家自然科学基金委员会A3前瞻计划重大国际合作项目（30921140311）;上海市重点学科建设资助项目（Y0205）

摘　　要：目的探讨叶酸干预对健康人外周血单个核细胞中肿瘤相关基因启动子甲基化状态的影响。方法健康志愿者10人，均分为2组，分别口服叶酸5mg或安慰剂，每日1次，连续3个月。于干预前后，以化学发光酶免疫分析试剂盒测定血清叶酸浓度，亚硫酸氢钠测序PCR（BSP）技术分别检测癌基因c—myc、C—Ha-ras，抑癌基因E—cadherin、p16INK4A和错配修复基因hMLH1的启动子甲基化状态。结果叶酸干预后，干预组血清叶酸水平显著升高（t=-4．739，P％0．05），而对照组无明显变化。叶酸干预3个月后，癌基因c—myc启动子甲基化率分别从干预前的4％、服用1周时的3．3％、服用1个月时的4．1％增加到8％（t=-4．079，P％0．05），而服用安慰剂者无明显变化。叶酸干预前后，其他肿瘤相关基因包括c—Ha-ras、E-cadherin、p16INK4A和hMLH1的启动子甲基化水平无明显改变。结论叶酸干预可升高癌基因c—myc启动子甲基化水平，但不影响抑癌基因E—eadherin、p16INK4A和hMLH1的甲基化状态。Objective To investigate the effect of folie acid on the DNA methylation of tumorrelated genes promoters in healthy human peripheral blood mononuclear cells（PBMC）. Methods Ten healthy volunteers were divided into two groups, and were randomized to receive either 5 mg folic acid （n=5）or placebo（n= 5）, one time per day for 3 months. The serum folic acid concentration was detected with chemiluminescence enzyme immunoassay kit before and after the intervention. The methylation statuses of five tumor-related genes promoter, including oncogenes c-myc, c-Ha-ras, tumor suppressor genes p16INK4A, E-cadherin and mismatch repair gene hMLH1 in PBMC were detected by bisufite sequencing. Results After folic acid intervention, the level of serum folic acid increased significantly in intervention group （t=-4. 739, P〈0.05）, however no significant difference in control group. After three-month folic acid intervention, the level of methylation of oncogene c-myc promoter increased from 4%, 3. 3%, 4. 1% before intervention, one week after intervention, one month after intervention respectively to 8 % （t =- 4. 079, P〈0.05）, while no significant change in placebo taken group. Before and after the folic acid intervention, there was no significant difference of DNA methylation of other tumor-related genes promoter, including c-Ha-ras, E-cadherin, p16INK4A and hMLH1. Conclusion Folic acid intervention can up-regulate DNA methylation of oncogene c-myc promoter, but can not affect the promoter methylation status of tumor suppressor genes E-cadherin, p16INK4A and hMLH1.

关 键 词：叶酸 DNA甲基化 基因 MYC 基因 肿瘤抑制 钙黏着糖蛋白类 基因 p16 单核细胞 

分 类 号：R965[医药卫生—药理学]