卵巢上皮性癌DNA异常甲基化模式的建立及其应用  

Model of aberrant DNA methylation patterns and its applications in epithelial ovarian cancer

作　　者：谷晓鸿[1] 卢媛[1] 马端[2] 刘惜时[1] 郭孙伟[3] 

机构地区：[1]复旦大学附属妇产科医院妇科,上海200032 [2]上海医学院分子医学教育部霞点实验室 [3]上海交通大学医学院妇产科学研究所

出　　处：《中华妇产科杂志》2009年第10期754-759,共6页Chinese Journal of Obstetrics and Gynecology

基　　金：基金项目：国家自然科学基金（30571952）

摘　　要：目的建立卵巢上皮性癌（卵巢癌）的DNA异常甲基化模式，探讨其在寻找新的卵巢癌特异性标志物中的应用价值。方法用激光显微切割技术从20例卵巢癌组织冰冻切片中获取的肿瘤细胞作为实验对象，用原代培养的5例正常卵巢上皮细胞作为对照，用基于芯片技术的差异甲基化杂交（DMH）方法检测卵巢癌的DNA异常甲基化模式。选择7个DMH结果显示在卵巢癌中低甲基化的基因启动子区胞嘧啶-磷酸-鸟嘌呤二核苷酸岛（CGI），用甲基化实时荧光定量PCR技术检测其在87例卵巢癌和42例卵巢良性病变患者病变组织中的甲基化状态。结果182个过甲基化位点和64个低甲基化位点（阳性率为25％以上的位点分别有18个和31个）组成了卵巢癌的DNA异常甲基化模式。87例卵巢癌和42例卵巢良性病变患者组织DNA中，基因LSM2、EGFLAM和CDKN2A的甲基化率依次为11％（10／87）和33％（14／42）、8％（7／87）和21％（9／42）、9％（8／87）和31％（13／42），与卵巢良性病变相比，卵巢癌中3个基因甲基化率均有显著下降，分别比较，差异均有统计学意义（P〈0．05）。结论建立卵巢癌的DNA异常甲基化模式是卵巢癌研究中非常重要的基础环节。基因EGFLAM、CDKN2A和LSM2启动子区CGI有可能成为新的卵巢癌特异性的低甲基化肿瘤标志物。Objective To profile methylation alterations of cytosine-phosphate-guanosine islands （CGI） in epithelial ovarian cancer and investigate its applications for finding new candidate tumor markers. Methods Cancer cells were obtained by laser microdissection from 20 tissues of frozen-preserved epithelial ovarian tumors. Primary cultured epithelial cells were isolated from 5 tissues of normal ovaries. Differential methylation hybridization （DMH） based on microarray assay was conducted using DNA to construct the aberrant DNA methylation pattern of epithelial ovarian cancer. MethyLight was conducted to verify the methylation status of 7 hypomethylated promoter CGI detected by DMH in tumor tissues of 87 patients with epithelial ovarian cancer and 42 patients with benign ovarian diseases. Results The aberrant DNA methylation pattern of epithelial ovarian cancer were included 182 hypermethylated loci and 64 hypomethylated loci, of which the positive loci located more than 25% arrays were 18 and 31, respectively. The methylation ratio of gene LSM2, EGFLAM and CDKN2A in tissue DNA of patients with epithelial ovarian cancer and benign ovarian diseases was 11% （ 10/87 ） versus 33% （ 14/42）, 8% （7/87） versus 21% （9/42）, 9% （8/87） versus 31% （13/42）, respectively, which was significantly decreased in tissues DNA of ovarian cancer than that from benign ovarian diseases （ P 〈 0. 05 ）. Conclusions The aberrant DNA methylation pattern of epithelial ovarian cancer is important for finding new cancer related genes. The promoter CGI of gene LSM2, EGFLAM and CDKN2A may be novel candidate for ovarian cancerspecific hypomethylated tumor markers.

关 键 词：卵巢肿瘤 DNA甲基化 CPG岛 肿瘤标记 生物学 

分 类 号：R686[医药卫生—骨科学]