类固醇硫酸酯酶在乳腺癌和正常乳腺组织中的表达及其意义

Expressions of steroid sulfatase in breast cancer tissues and normal breast tissues and its significance

目的:探讨类固醇硫酸酯酶(steroid sulfatase,STS)蛋白及其mRNA在乳腺癌组织及相对应的正常乳腺组织中的表达,以及与临床病理特征之间的关系。方法:分别应用免疫组织化学SP法和RT-PCR法检测40例乳腺癌患者乳腺癌组织及其对应的癌旁正常乳腺组织中STS蛋白和mRNA的表达水平,并进行比较,同时分析STS蛋白表达与临床病理特征之间的关系。结果:STS蛋白主要表达于乳腺癌细胞和正常乳腺组织上皮细胞的细胞质内,有3例患者乳腺癌细胞的细胞核中可见STS蛋白的表达,乳腺间质组织未见STS蛋白表达。乳腺癌组织及正常乳腺组织中STS蛋白的表达水平与其mRNA的表达水平均呈正相关。乳腺癌组织中STS蛋白的阳性表达率(70.0%)明显高于其对应的正常乳腺组织(42.5%),差异有统计学意义(P=0.013)。分层分析显示,绝经前、淋巴结转移和病理分期较晚的乳腺癌患者,其乳腺癌组织中STS蛋白的阳性表达率明显高于其对应的正常乳腺组织(P<0.05)。结论:乳腺癌组织可能通过高表达STS以促进自身合成雌激素,提高肿瘤局部的雌激素水平,从而促进肿瘤的生长和转移。同时,随着肿瘤的生长,肿瘤局部合成的雌激素在肿瘤生长中的作用可能越来越重要。

Objective：To investigate the mRNA and protein expressions of steroid sulfatase（STS） in breast cancer tissues and normal breast tissues,and analyze its relationship with clinicopathologic characteristics.Methods：The mRNA and protein expressions of STS,in 40 cases of breast cancer tissues and corresponding paracancerous normal breast tissues,were examined by reverse transcription-polymerase chain reaction（RT-PCR）and immunohistochemistry.The correlation of STS expression level with clinicopathologic characteristics was analyzed.Results：STS protein was mainly expressed in the cytoplasm of breast carcinoma cells and epithelial cells in normal breast glands,but not in the stroma.It could be detected in the nucleus of carcinoma cells in 3 cases of breast cancer tissues,which was pathologically classified as invasive ductal carcinoma,invasive lobular carcinoma,and invasive micropapillary carcinoma.STS was not observed in interstitial tissues of breast glands.STS protein expression had positive correlation with its mRNA expressing level.The positivity of STS was 70.0% in breast cancer tissues,significantly higher than that of normal breast tissues（42.5%）.The difference was significant（P =0.013）.Stratified analysis showed that the positive rates of STS protein were significantly higher in premenopausal patients,the patients with lymph node metastasis,and those with advanced breast carcinoma than those in the matched normal breast tissues（P0.05）.Conclusion：Breast cancer tissues highly expressed STS protein to stimulate local estrogen production,thereby enhancing the progression and migration of breast cancer cells.In addition,as the tumor growth,locally biosynthesized estrogens may play more and more important roles.