乳腺癌发生模型MCF10各阶段细胞系中TIMP3基因启动子区甲基化分析

目的探讨抑癌基因TIMP3失活与乳腺癌发生和进展的关系。方法用甲基化特异性PCR技术和亚硫酸盐测序技术检测乳腺癌发生模型MCF10的增生细胞系MCF10A、癌前细胞系MCF10AT、导管内癌细胞系MCF10DCIS.com、浸润癌细胞系MCF10CA1a和转移癌细胞系MCF10CA1d、MCF10CA1h中TIMP3启动子区甲基化状态。结果甲基化特异性PCR分析显示,在上述各细胞系中,TIMP3启动子区均呈高度甲基化状态。亚硫酸盐测序显示,在上述各细胞系中,测序区内的68个CG位点几乎全部发生了甲基化,且甲基化累及了绝大部分等位基因。结论TIMP3基因启动子区甲基化在乳腺癌的发生和进展中起重要作用,可能成为早期诊断乳腺癌和判断乳腺癌预后的分子生物学标记。

Promoter methylation of TIMP3 gene in the cell lines of MCF10 breast cancer model

Purpose To investigate the roles of TIMP3 gene inactivation in the development and progression of breast cancer. Methods Methylation specific PCR and sodium bisufite genomic sequencing were employed to detect methylation status of TIMP3 promoter in MCF10 model cell lines including MCF10A (breast hyperplastic cell line, non-tumorigenic), MCF10AT (pre-malignant cell line, forms slowly progressing hyper and dysplastic lesions), MCF10DCIS.com (breast ductal carcinoma in situ cell line, forms ductal carcinoma in situ), MCF10CA1a(invasive breast carcinoma cell line, forms aggressive tumors of different morphology), MCF10CA1d, MCF10CA1h cell lines(metastatic breast carcinoma cell lines). Results Hypermethylation of TIMP3 gene promoter region, which was involved in majority of alleles, was identified in the breast hyperplastic cell line, pre-malignant cell line, ductal carcinoma in situ cell line, invasive carcinoma cell line and metastatic breast carcinoma cell lines. Conclusions Aberrant promoter methylation of TIMP3 gene may play an important biologic role in breast cancer development and progression, and might be one of potential markers for breast diagnosis in early stage and for prognosis evaluation.