细胞分裂周期相关蛋白7通过增强细胞增殖和干性促进人乳腺癌进程

Cell division cycle associated 7 promoteing breast cancer progression by enhancing proliferation and stemness of breast cancer cell

目的探讨细胞分裂周期相关蛋白7(CDCA7)在人类乳腺癌中的相关功能及潜在的作用机制。方法通过癌症和肿瘤基因图谱(TCGA)数据库分析检索出不同乳腺癌亚型差异表达基因,找到在基底型乳腺癌中高表达基因,在这些基因中找到CDCA7,通过临床患者的相关标本做免疫组织化学分析,确定其研究意义,进而建立CDCA7稳转细胞系,通过集落形成实验、成球实验及流式细胞术分析研究其在乳腺癌中的功能,最后通过Realtime PCR及Western blotting实验分析其在乳腺癌中的分子机制。结果数据库和免疫组织化学结果均显示,CDCA7在基底型乳腺癌细胞中表达高于其他亚型,高表达的CDCA7预示乳腺癌患者不良预后。在luminal细胞系中稳定地过表达CDCA7后,细胞表现出更强的增殖能力,进入分裂期的细胞明显增多,而凋亡细胞显著减少。同时流式细胞术分析表明,过表达CDCA7的细胞表现出了干细胞标记(CD133,乙醛脱氢酶)上调。Real-time PCR和Western blotting结果提示,CDCA7能够上调β-连环蛋白(β-catenin)表达,以此影响Wnt信号通路,并影响细胞增殖和干性。结论 CDCA7作为一个促瘤基因,能够通过依赖β-catenin以及Wnt信号通路的方式来诱导luminal乳腺癌细胞向basal-like亚型转化的能力。

Objective To investigate the role of cell division cycle associated 7( CDCA7) in breast cancer and the potential mechanisms among the progressioned. Methods By data analysis in data base to retrieve the differential expression gene and find out highly expressed genes in basal-like breast cancer cells. Among these genes we selected the attractive CDCA7 as the target of investigation. Through specimen immunohistochemistry analysis of clinical patients to confirm the significance of the research. Then we constructed CDCA7 stable expression cell lines to preform a series of experiments including colony formation assays,tumorsphere formation assays,flow cytometry,Western blotting and Realtime PCR to clear the role of CDCA7 in breast cancer. Results Data base analysis and histochemistry showed CDCA7 was highly expressed in basal-like breast cancer cells and high expression of CDCA7 predicts poor prognosis. Overexpressing CDCA7 in luminal cell lines,the cell lines showed stronger proliferative capacity,more mitotic cell and less apoptotic cell.Meanwhile,the markers of stem cell,such as CD133 and acetaldehyde dehydrogenase( ALDH) showed being upregulated.The Real-time PCR and Western blotting analysis showed that CDCA7 increased the expression of β-catenin,through which CDCA7 effected the Wnt pathway so as to influence cell proliferation and stemness. Conclusion CDCA7 as a oncogenic gene induces luminal cell to transform to basal-like subtype by depending on β-catenin and Wnt pathway.