RNF8 promotes epithelial-mesenchymal transition of breast cancer cells.
RNF8 promotes epithelial-mesenchymal transition of breast cancer cells.
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RNF8促进乳腺癌细胞上皮间质转化
DOI：
10.1186/s13046-016-0363-6
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发表时间：
2016-06-04
期刊：
影响因子：
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通讯作者：
Shao G
中科院分区：
文献类型：
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作者：
Kuang J;Li L;Guo L;Su Y;Wang Y;Xu Y;Wang X;Meng S;Lei L;Xu L;Shao G
研究背景上皮间质转化（epithelial-mesenchymaltransition，EMT）是实体瘤发生发展的关键步骤，在肿瘤的侵袭和转移中起重要作用。RNF 8是一种具有RING结构域的泛素E3连接酶，在DNA损伤反应和细胞周期调控中发挥重要作用。然而RNF 8在乳腺癌发病机制中的作用尚不清楚。方法采用Western Blotting方法检测RNF 8在不同类型乳腺细胞系中的表达。当RNF 8异位过表达时，在MCF-7中通过免疫荧光和蛋白质印迹法检测EMT相关标志物，或者当RNF 8耗尽时，在MDA-MB-231中通过免疫荧光和蛋白质印迹法检测EMT相关标志物。进行Transwell和伤口愈合测定以评估RNF 8对细胞移动性的影响。采用裸鼠移植瘤模型研究RNF 8在肿瘤转移中的作用。采用免疫组织化学方法检测乳腺组织芯片中RNF 8的表达。使用在线工具（ http://kmplot.com/analysis/ 结果RNF 8在高转移乳腺癌细胞系中过表达。RNF 8在MCF-7中的过表达显著促进EMT表型和促进细胞迁移。相反，MDA-MB-231中RNF 8的沉默诱导MET表型并抑制细胞迁移。此外，我们证明RNF 8在乳腺癌中的这些转移行为促进作用与GSK-3β的失活和β-catenin信号通路的激活有关。在裸鼠移植瘤模型中，我们发现RNA干扰下调RNF 8基因的表达可以减少肿瘤的转移。结论RNF 8可诱导乳腺癌细胞发生EMT，促进乳腺癌转移，提示RNF 8可作为乳腺癌防治的潜在靶点。
BackgroundEpithelial-mesenchymal transition (EMT) is a crucial step for solid tumor progression and plays an important role in cancer invasion and metastasis. RNF8 is an ubiquitin E3 ligase with RING domain, and plays essential roles in DNA damage response and cell cycle regulation. However the role of RNF8 in the pathogenesis of breast cancer is still unclear.MethodsThe expression of RNF8 was examined in different types of breast cell lines by Western Blotting. EMT associated markers were examined by Immunofluorescence and Western Blotting in MCF-7 when RNF8 was ectopically overexpressed, or in MDA-MB-231 when RNF8 was depleted. Transwell and wound healing assays were performed to assess the effect of RNF8 on cell mobility. The xenograft model was done with nude mice to investigate the role of RNF8 in tumor metastasis in vivo. Breast tissue arrays were used to examine the expression of RNF8 by immunohistochemistry. Kaplan-Meier survival analysis for the relationship between survival time and RNF8 signature in breast cancer was done with an online tool ( http://kmplot.com/analysis/ ).ResultsRNF8 is overexpressed in highly metastatic breast cancer cell lines. Overexpression of RNF8 in MCF-7 significantly promoted EMT phenotypes and facilitated cell migration. On the contrary, silencing of RNF8 in MDA-MB-231 induced MET phenotypes and inhibited cell migration. Furthermore, we proved that these metastatic behavior promoting effects of RNF8 in breast cancer was associated with the inactivation of GSK-3β and activation of β-catenin signaling. With nude mice xenograft model, we found that shRNA mediated-downregulation of RNF8 reduced tumor metastasis in vivo. In addition, we found that RNF8 expression was higher in malignant breast cancer than that of the paired normal breast tissues, and was positively correlated with lymph node metastases and poor survival time.ConclusionsRNF8 induces EMT in the breast cancer cells and promotes breast cancer metastasis, suggesting that RNF8 could be used as a potential therapeutic target for the prevention and treatment of breast cancer.