HEY1负向调控miR-451参与化疗诱导的非小细胞肺癌上皮-间质转化表型形成的作用及分子机制

The main reasons for treatment failure of non-small cell lung cancer (NSCLC) patients are tumor chemoresistance and metastasis, and epithelial-mesenchymal transition (EMT) plays vital roles during those two processes. Under the support of previous National Natural Science Foundation of China, we have shown that miR-451 is significantly downregulated in the cisplatin-resistant NSCLC cell line (A549/DDP) and upregulation of miR-451 can reverse the chemoresistance and EMT of A549/DDP cell line. However, the roles of miR-451 in chemotherapy-induced EMT phenotype of NSCLC cells and its transcriptional activity are still unclear. On the basis of identifying chemotherapy-induced EMT phenotype, transcription factor expression array screen and bioinformatics analysis, the aim of this study is to verify the association of transcriptional regulation between HEY1 and miR-451 by luciferase activity, electrophoretic mobility shift, co-immunoprecipitation and site-specific mutation assays. Additionally, the roles of HEY1 in chemotherapy-induced EMT formation and metastasis enhancement of NSCLC cells by transcriptional inhibition of miR-451 expression will be investigated. This will helpful to provide novel molecular targets for overcoming chemoresistance and tumor metastasis of human NSCLC.

耐药和转移是非小细胞肺癌（NSCLC）患者治疗失败的主要原因。而上皮-间质转化在化疗耐药及远处转移的发生中扮演着非常重要的角色。在前一个国家自然科学基金资助下，我们发现：miR-451在顺铂耐药的NSCLC细胞(A549/DDP)中呈现显著的低表达，其表达水平上调能显著逆转细胞的耐药性及EMT表型。但是miR-451在化疗诱导的EMT表型形成中的作用及其转录调控机制并不清楚。在前期NSCLC耐药细胞EMT表型鉴定、转录因子芯片筛选及生物信息学分析的基础上，本课题拟通过荧光素酶活性测定、凝胶阻滞、免疫共沉淀和位点突变实验明确HEY1与 miR-451之间的转录调控关系，并通过体内外功能学实验，探讨HEY1通过转录抑制miR-451参与化疗诱导的NSCLC细胞EMT表型形成及侵袭转移活性升高的作用，从而为临床逆转NSCLC化疗耐药和抗肿瘤转移治疗提供新的靶点。

耐药和转移是非小细胞肺癌（NSCLC）患者治疗失败的主要原因。而上皮-间质转化（EMT）在化疗耐药及远处转移的发生中扮演着非常重要的角色。在前一个国家自然科学基金资助下，我们发现：miR-451在顺铂耐药的NSCLC细胞（A549/DDP）中呈现显著的低表达，其表达水平上调能显著逆转细胞的耐药性及EMT表型。在前期NSCLC顺铂耐药细胞EMT表型鉴定、转录因子芯片筛选及生物信息学分析的基础上，我们通过荧光素酶报告试验、Western blot及功能学拯救实验证实了HEY1与 miR-451之间的转录调控关系，并探讨了HEY1通过转录抑制miR-451继而调控下游E-cadherin、N-cadherin、vimentin等EMT相关分子及 c-Met、MMP2等转移相关基因的表达参与调控非小细胞肺腺癌顺铂耐药表型形成及侵袭转移活性升高的作用，旨在为临床逆转NSCLC化疗耐药和抗肿瘤转移治疗提供新的靶点。