NEK7通过调控NF45-NF90复合体促进肝癌进展和转移的分子机制研究

Hepatocelluar carcinoma (HCC) is one of the most common tumors in the world. NEK (NIMA-related kinase) family was firstly found to be involved in the regulation of the cell cycle, however, little is known about the role of NEK7 in the development and metastasis of HCC. Our previous study found that NEK7 promoted the proliferation, invasion and metastasis of HCC cells. Meanwhile, protein immunoprecipitation mass spectrometry analysis detected that NEK7 interacted with NF45. Both endogenous and exogenous IP experiments showed that NEK7 can bind NF45-NF90 complex. Therefore, we hypothesize that NEK7 promotes the progression and metastasis of HCC by regulating the NF45-NF90 complex. We intend to use molecular biology, proteomics, miRNA chipsand other means to study the following issues in HCC: 1. To evaluate NEK7 promotes tumor proliferation and metastasis by in vitro and in vivo experiments; 2. To confirm whether NEK7 kinase activity is essential for tumor metastasis; 3. to study the mutual regulation relationship between NEK7 and NF45-NF90; 4. to investigate the role of NF45 in HCC and which miRNA can be regulated by the complex NF45-NF90 in HCC. The project will provide a new insight to the multi-targeting therapeutics for the metastasis of HCC.

肝癌是世界上最常见的肿瘤之一，NEK(NIMA-related kinase)家族最早发现参与细胞周期的调控，其重要成员NEK7在肝癌发展与转移中的作用知之甚少。申请人前期研究发现NEK7能够促进肝癌细胞增殖和侵袭转移。同时蛋白免疫共沉淀结合质谱检测发现，NEK7能够结合NF45。内源性和外源性IP实验证明，NEK7能够结合NF45-NF90复合体。据此我们假设：NEK7通过调控NF45-NF90复合体促进肝癌进展和转移。我们拟运用分子生物学，蛋白组学和miRNA芯片等手段研究以下四个问题：1、体内体外实验证明NEK7能够促进肿瘤增殖与转移；2、NEK7促肿瘤转移是否依赖其激酶活性；3、NEK7如何调控NF45-NF90复合体；4、NF45在肝癌中的作用，及复合体NF45-NF90在肝癌中调控哪些miRNA成熟。本课题将加深对肝癌发生和转移机制的了解，为其多靶点联合治疗提供新思路。

肝癌是世界上最常见的肿瘤之一，NEK(NIMA-related kinase)家族最早发现参与细胞周期的调控，本研究主要探究NEK7在肝癌发生及进展中发挥的关键作用以及相关的分子机制。前期分子功能学研究提示NEK7促进肝细胞癌的增殖和侵袭转移过程。质谱分析我们发现NEK7能够与EGFR与P85α相互结合，而且NEK7主要参与EGFR-P85α-AKT通路，但对EGFR-ERK通路没有影响。在EGF的刺激下EGFR可以酪氨酸磷酸化P85α的201和202位点，从而激活NEK的激酶活性。激活的NEK7能够序贯磷酸化P85α的苏氨酸的603位点，从而增强P85在细胞膜上的与EGFR的结合。本研究第一次找到在EGFR/P85α/AKT通路调控中的关键分子，并为EGFR激活下游PI3K/AKT提供更加精准分子调控的理论基础。