乳腺癌肿瘤抑制候选基因5基因启动子甲基化水平研究

摘要

To investigate the promoter methylation status of TUSC5 gene in human breast cell and human breast cancer cell lines, and the relationship between hormone receptor and HER-2 status of TUSC5 expression. Pyrosequencing is used to measure the promoter methylation status of TUSC5 gene in four human breast cancer cell lines and one human breast cell. qRT-PCR and Western blot are used to detect the mRNA and protein expressions of TUSC5 gene. It is found that the human breast cell line(MCF-10A) shows low-methylated status and 4 human breast cancer cell lines show high-methylated status. However, the high-methylated status of the breast cancer line with the negative expressions of ER/PR and HER-2(TNBC, triple-negative breast cancer) is lower than the non-triple-negative breast cancer cell lines. Pathogenesis of breast cancer may be connected with the promoter methylation status of TUSC5 gene in human breast cancer, and its high-methylated status is related to the expression of hormone receptor and HER-2, but the mechanism is currently unknown and needs being further studied.%探讨人正常乳腺细胞株及不同乳腺癌细胞株肿瘤抑制候选基因5启动子甲基化状态，并分析其与雌激素受体、孕激素受体、人类表皮生长因子受体2的表达相关性。运用焦磷酸测序分析4种乳腺癌细胞株和1种人类正常乳腺细胞株中TUSC5基因启动子甲基化状态，以及实时荧光定量逆转录聚合酶反应和Western印迹来检测这些细胞株中TUSC5基因mRNA和蛋白的表达。结果表明：正常人类乳腺细胞株存在TUSC5基因启动子低甲基化，而4种乳腺癌细胞株存在不同程度高甲基化；在4种乳腺癌细胞株中，激素受体及 HER-2表达阴性即三阴性乳腺癌细胞TUSC5基因启动子甲基化水平较非三阴性乳腺癌细胞低；并且乳腺癌的发生可能与TUSC5基因启动子高甲基化有关，乳腺癌TUSC5基因启动子甲基化水平与激素受体、HER-2表达具有一定相关性，其发生的机制需进一步研究探讨。