Yan Zhantao, Gao Shan, Wu Xia, Liu Hui
Department of Pathology, Xuzhou Medical College, Xuzhou 221002, China.
Department of Pathology, Xuzhou Medical College, Xuzhou 221002, China; E-mail:
Zhonghua Bing Li Xue Za Zhi. 2015 Apr;44(4):240-4.
To investigate the relationship between hypermethylation of Runx3 gene promoter and estrogen receptor (ER) and the implications of Runx3 gene promoter hypermethylation in ER positive breast cancer.
Western blot and RT-PCR were used to detect the protein and mRNA expression of Runx3 gene in breast cancer cell lines (MCF7 and SKBR3) and normal breast epithelium cell line (MCF10A). Immunohistochemical SP method was used to detect the expression of ER and Runx3 proteins in 113 tissue samples of breast cancer. Moreover, methylation specific PCR was used to detect RUN3 promoter methylation in cell lines MCF7, SKBR3, MCF10A and 113 tissue samples of breast cancer.
Of the 3 cell lines, Runx3 protein and mRNA were detectable in MCF10A, but were absent in MCF7 and SKBR3. MCF7 had a high methylation status at Runx3 promoter, in contrast, MCF10A and SKBR3 showed unmethylated RUN3 promoter. Among the 113 cases of breast cancer, 68 cases were ER positive and 45 were negative. The positive rates of Runx3 protein expression in ER positive and negative tumors were 26.5% (18/68) and 66.7% (30/45), respectively (P<0.05). Runx3 promoter hypermethylation was seen in 82.4% (56/68) of ER positive breast cancer cases and 22.2% (10/45) of ER negative ones (P<0.05). Among 68 cases of ER positive cases, Runx3 promoter hypermethylation was positively correlated with the clinical tumor stage (OR=5.84, P<0.05).
Runx3 gene promoter hypermethylation is present mainly in the ER positive breast cancers. Testing of Runx3 promoter methylation may provide additional reference for clinical stage and prognosis of breast cancer patients, especially in those with ER positive tumors.
探讨Runx3基因启动子高甲基化与雌激素受体（ER）的关系以及Runx3基因启动子高甲基化在ER阳性乳腺癌中的意义。
采用蛋白质免疫印迹法（Western blot）和逆转录-聚合酶链反应（RT-PCR）检测乳腺癌细胞系（MCF7和SKBR3）及正常乳腺上皮细胞系（MCF10A）中Runx3基因的蛋白和mRNA表达。采用免疫组织化学SP法检测113例乳腺癌组织标本中ER和Runx3蛋白的表达。此外，采用甲基化特异性PCR检测MCF7、SKBR3、MCF-10A细胞系及113例乳腺癌组织标本中RUN3启动子甲基化情况。
在3种细胞系中，MCF10A可检测到Runx3蛋白和mRNA，而MCF7和SKBR3未检测到。MCF7的Runx3启动子甲基化程度高，相反，MCF10A和SKBR3的RUN3启动子未甲基化。113例乳腺癌中，68例ER阳性，45例ER阴性。ER阳性和阴性肿瘤中Runx3蛋白表达阳性率分别为26.5%（18/68）和66.7%（30/45）（P<0.05）。ER阳性乳腺癌病例中82.4%（56/68）存在Runx3启动子高甲基化，ER阴性病例中22.2%（10/45）存在Runx3启动子高甲基化（P<0.05）。在68例ER阳性病例中，Runx3启动子高甲基化与临床肿瘤分期呈正相关（OR=5.84，P<0.05）。
Runx3基因启动子高甲基化主要存在于ER阳性乳腺癌中。检测Runx3启动子甲基化可为乳腺癌患者尤其是ER阳性肿瘤患者的临床分期及预后提供额外参考。
