The Relationship between Methylation and Expression Defect of Tumor Suppressor Gene p16INK4A in Epithelial Ovarian Cancer  

上皮性卵巢癌中p16INK4A表达缺陷与甲基化的关系(英文)

作　　者：李敏[1] 董卫红[1] 李晓艳[1] 王泽华[1] 

机构地区：[1]武汉市华中科技大学同济医学院附属协和医院妇产科,430022

出　　处：《The Chinese-German Journal of Clinical Oncology》2006年第3期204-208,共5页中德临床肿瘤学杂志（英文版）

基　　金：This work was supported by grant from the National Natural Science Foundation of China (No. 30070786)as well as Scientific and Technological Development Plan of Hubei Province of China

摘　　要：Objective： To evaluate the expression of p16INK4A gene in ovarian cancer and analyze the relation between this alteration and the promoter methylation of p16INK4A DNA. Methods： Seven ovarian cancer cell lines and eighteen ovarian cancer specimens were selected for the study. Genomic DNA and RNA were extracted from fresh tissues and cell lines, DNA was treated with sodium bisulfite and then analyzed with methylation-specific PCR （MSP） to detect p16INK4A methylation. The expression of p16INK4A mRNA was detected by reverse transcription-polymerase chain reaction （RT-PCR）. In addition, the proliferation of methylated cell lines before and after treatment of demethylating agent 5-Aza-2＇-deoxycytidine （5-ADC） was examined with 3-（4, 5-dimethylthiazol-2-yl）-2, 5-diphenyltetrazolium bromide （MTT） assay in vivo. Results： Compared with the control, the expression of p16INK4A mRNA decreased significantly or absolutely defaulted in 10 of 18 （55.56%） ovarian cancer specimens and 71.4% （5/7） ovarian cancer cell lines （P〈0.05）, and the expression of p16INK4A protein also decreased （P〈0.05）. The decrease of p16INK4A was due, in part, to p16INK4A methylation, which was found in the first exon of three cell lines and six ovarian cancer specimens and the rate was 42.86% and 33.33% in ovarian cancer cell lines and specimens respectively. All the methylated cells and tissues showed expression defect of p16INK4A, but the treatment of 5-ADC reactivated the expression of p16INK4A in methylated cells and decreased the proliferation of tumor cells in vitro and in vivo. Conclusion： The expression defect of p16INK4A gene possibly has an important role in the development of ovarian cancer, and this alteration is due, in part, to the methylation of the first exon in p16INK4A.

关 键 词：ovarian neoplasm P16INK4A METHYLATION 5-Aza-2＇-deoxycytidine 

分 类 号：R737.31[医药卫生—肿瘤]