RNF43 ubiquitinates and degrades phosphorylated E-cadherin by c-Src to facilitate epithelial-mesenchymal transition in lung adenocarcinoma
RNF43 ubiquitinates and degrades phosphorylated E-cadherin by c-Src to facilitate epithelial-mesenchymal transition in lung adenocarcinoma
复制标题
RNF43 通过 c-Src 泛素化并降解磷酸化 E-钙粘蛋白，促进肺腺癌中的上皮-间质转化
DOI：
10.1186/s12885-019-5880-1
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发表时间：
2019-07-08
期刊：
影响因子：
3.8
通讯作者：
Zhao, Yang
中科院分区：
文献类型：
--
作者：
Zhang, Yunfeng;Sun, Liangzhang;Zhao, Yang
背景在上皮细胞中，酪氨酸激酶诱导E-cadherin复合物的酪氨酸磷酸化和泛素化，这是上皮间质转化（EMT）的原因。然而，精确的mechanisms仍然不清楚。MethodsProtein antibody microarray analysis和E3 ligase profiling进行检测独特的E3 ligase潜在的E-cadherin下调肺腺癌组织。使用病毒shRNA进行基因敲除。免疫印迹，免疫荧光，免疫沉淀，并在体内异种移植模型被整合应用于探索RNF 43诱导的EMT在肺腺癌细胞株.ResultsProtein抗体微阵列分析和E3连接酶分析显示，环指蛋白43（RNF 43）被链接到E-钙粘蛋白下调的背景下，在肺腺癌组织中的c-Src激活。此外，c-Src-Caspase-8相互作用显著增加c-Src活性。激活的c-Src在酪氨酸797位点磷酸化E-钙粘蛋白，以启动RNF 43介导的E-钙粘蛋白在赖氨酸816处的泛素化和随后的降解，从而允许β-连环蛋白的核转位以及肺腺癌细胞中波形蛋白和RNF 43表达的上调。E-cadherin表达减少和Vimentin表达增加可诱导EMT表型并促进肿瘤转移。Frizzled 8（Frz 8）-RNF 43诱导的磷酸化E-cadherin泛素化可被抗Frz 8的CRD单克隆抗体阻断，但不能被抗RNF 43的PA单克隆抗体阻断。结论RNF 43通过激活的c-腺苷酸受体（c-腺苷酸受体）对磷酸化E-cadherin的泛素化和降解，参与肺腺癌转移过程中EMT的调控。Src.
BackgroundIn epithelial cells, tyrosine kinases induce tyrosine phosphorylation and ubiquitination of the E-cadherin complex, which is responsible for the epithelial-mesenchymal transition (EMT). However, the precise mechanisms remain unclear.MethodsProtein antibody microarray analysis and E3 ligase profiling were performed to detect the unique E3 ligase underlying E-cadherin downregulation in lung adenocarcinoma tissues. Gene knockdown was performed using viral shRNA. Immunoblotting, immunofluorescence, immunoprecipitation, and xenograft models in vivo were integratively applied to explore RNF43-induced EMT in lung adenocarcinoma cell lines.ResultsProtein antibody microarray analysis and E3 ligase profiling revealed that the RING finger protein 43 (RNF43) was linked to E-cadherin downregulation within the context of c-Src activation in lung adenocarcinoma tissues. In addition, the c-Src-Caspase-8 interaction markedly increased c-Src activity. Activated c-Src phosphorylated E-cadherin at the tyrosine 797 site to initiate RNF43-mediated E-cadherin ubiquitination at lysine 816 and subsequent degradation, thus allowing the nuclear translocation of β-catenin and upregulation of Vimentin and RNF43 expression in lung adenocarcinoma cells. Decreased E-cadherin expression and increased Vimentin expression induced the EMT phenotype and promoted tumor metastasis. The Frizzled 8 (Frz8)-RNF43-induced ubiquitination of phosphorylated E-cadherin was blocked by a monoclonal antibody against the cysteine-rich domain (CRD) of Frz8 but not by antibodies against the protease domain (PA) of RNF43.ConclusionsOur data suggest that RNF43 participates in the regulation of EMT in the metastasis of lung adenocarcinoma through the ubiquitination and degradation of phosphorylated E-cadherin by activated c-Src.