Objective: To investigate the expression and significance of ubiquitin-specific proteases 2-69(USP2-69) in invasive ductal carcinoma of breast. Methods: Twenty-four cases of human breast tissue with invasive ductal carcinoma diagnosed at Huanshan Hospital, Fudan University from 2013 to 2015 were collected, and the expression of USP2-69 mRNA and protein was detected by molecular hybridization, Western blot and immunohistochemistry. USP2-69 was over-expressed in cultured human breast cancer cell line MCF-7 by USP2-69 plasmid transfection. The cellular proliferative activity was investigated in vitro. Results: The USP2-69 mRNA and protein were highly expressed in breast invasive ductal carcinoma, compared to adjacent normal tissues (P<0.01). Ki-67 protein expression was also increased in cases with high USP2-69 protein level. Western blot showed significantly higher USP2-69 protein level in cancer tissue compared to the adjacent normal tissue. In the cultured tumor cells, there was increased S phase fraction, cellular proliferation rate, flat positive clones, cyclin D1 expression and decreased p27 expression in USP2-69-transfected MCF-7 cells. Conclusions: USP2-69 is over-expressed in breast invasive ductal carcinoma, and is closely related to proliferation promoting effects. The data provide an important experimental basis for further study on the molecular mechanism of breast cancer cell proliferation.
目的： 探讨泛素特异性加工酶2－69(USP2－69)在乳腺浸润性导管癌中的表达及意义。 方法： 收集2013至2015年复旦大学附属华山医院24例人乳腺浸润性导管癌组织，分别应用分子杂交技术、Western blot及免疫组织化学法检测其USP2－69 mRNA和蛋白水平表达。采用体外人乳腺癌细胞株MCF－7瞬时转染USP2－69质粒，使其过表达USP2－69，检测细胞增殖能力。 结果： 乳腺浸润性导管癌的肿瘤组织中，USP2－69在mRNA及蛋白水平均高表达，与癌旁组织相比差异有统计学意义(P<0.01)。USP2－69蛋白高表达的组织其Ki－67的蛋白表达也升高，Western blot免疫印迹法检测发现人乳腺浸润性导管癌组织中USP2－69的蛋白表达显著高于癌旁组织。细胞实验中转染USP2－69质粒的MCF－7细胞中cyclin D1较空载组表达增高，p27表达下降。细胞增殖速度明显加快，S期比例明显增高，平板阳性克隆明显增加(P<0.01)。 结论： 乳腺浸润性导管癌组织中USP2－69表达升高，与促进肿瘤细胞增殖能力密切有关。实验结果为进一步研究调节乳腺癌增殖的分子机制提供重要的实验基础。.
Keywords: Carcinoma, ductal, breast; Cell proliferation; Ubiquitin-specific proteases 2-69.