抑癌基因RIZ1启动子区甲基化与卵巢癌的关系

The relationship between methylation of RIZ1 gene in promoter region and genesis of ovarian cancer

目的:探讨抑癌基因RIZ1启动子区甲基化与卵巢上皮性癌发生的关系。方法:以卵巢癌组织及卵巢癌细胞系为研究对象。MSP检测RIZ1基因甲基化状况;RT-PCR、蛋白印迹分别检测RIZ1mRNA及蛋白表达;细胞增殖实验检测5-杂氮-2'-脱氧胞苷处理卵巢癌细胞前后细胞的增殖状况。结果:卵巢癌组织、卵巢癌细胞系、良性卵巢肿瘤组织及正常卵巢组织中的甲基化率分别为25.8%、40%、0%和0%。5-杂氮-2'-脱氧胞苷处理RIZ1基因发生甲基化的卵巢癌细胞系后,RIZ1基因重新获得表达;且去甲基化处理后,卵巢癌细胞生长均减慢。结论:抑癌基因RIZ1启动子区甲基化与上皮性卵巢癌的发生有关,DNA甲基化是其表达缺陷的原因之一。

Objective： To investigate the correlation between methylation of RIZ1 gene in promoter region and the genesis of epithelial ovarian cancer. Methods： Genomic DNA was isolated from ovarian cancer tissue specimens and ovarian cancer cell lines. Methylation - specific PCR （MSP） was used to check methylation of RIZ1 promoter region. The RIZ1 mRNA expression was detected by RT - PCR and the RIZ1 proptein was examined by Western blot. The demethylating agent, 5 -aza- 2＇- deoxycytidine, was used to treat methylated ovarian cancer cells and then, ovarian cancer cell growth was measured in vitro. Results： Methylation indices for ovarian cancer, ovarian cancer cell lines, benign ovarian tumor and normal ovarian tissue were 25. 8%, 40%, 0 and 0 respectively. 5 -aza -2＇-deoxycytidine reactivated the expression of RIZ1 in methylated cells and decreased the cell growth in vitro. Conclusion： Methylation of RIZ1 gene is a frequent event in ovarian cancer and is an important mechanism for loss of the gene expression. Aberrant methylation of RIZ1 gene may play a role in the pathogenesis of ovarian cancer.