Aurora-A激酶通过抑制LKB1/AMPK通路促进非小细胞肺癌侵袭和转移的机制研究

The LKB1 serine-threonine kinase is a tumor suppressor that is inactivated in a large number of sporadic human lung non–small cell carcinomas (NSCLCs). LKB1 directly activates a family of 14 kinases related to AMPK [adenosine monophosphate (AMP)–activated protein kinase] to control cell metabolism, growth, and polarity, though which of these are critical to its tumor suppressor functions remain undefined. LKB1 is also one.of the most commonly mutated genes in sporadic human lung cancer, particularly in multiple subtypes of NSCLC, where at least 15 to 35% of cases have this lesion. We analyzed 1404 NSCLC patients’ clinical data from GEO database in NCBI, and found that high expressed Aurora-A patients have a poor prognosis. And the expression of Aurora-A affects the recurrence and metastasis of NSCLC. Then, we found that Aurora-A can phosphorylate LKB1 in vitro and in vivo, and inhibit the LKB1/AMPK pathway in NSCLC, induce the invasion and metastasis..Our major is found the mechanism of Aurora-A inhibit the LKB1/AMPK pathway in NSCLC, and indicate the function of Aurora-A induce the invasion and metastasis in NSCLC. Aurora-A kinase inhibitor MLN8237 was used to II stage clinical trial and we want to find its benefit for inhibits Aurora-A and induce LKB1/AMPK pathway, then inhibitor invasion and metastasis in LKB1 positive NSCLC. We also try to establish the LKB1 positive NSCLC mouse model, and then we want to find a specific marker and treatment in the NSCLC.

在非小细胞肺癌（NSCLC）的发生和发展中，LKB1/AMPK信号通路起着非常关键的作用。LKB1的失活能导致肺癌的进展并促进转移，基因突变可引起LKB1表达的缺失，而蛋白水平的磷酸化、乙酰化等作用也可以引起LKB1活性的降低，从而导致LKB1失活。本课题组前期发现Aurora-A高表达的肿瘤预后差、转移率高。进一步研究发现Aurora-A激酶能通过磷酸化LKB1，从而抑制LKB1/AMPK信号通路，促进非小细胞肺癌的进展和转移。.本项目拟研究Aurora-A对LKB1/AMPK信号通路的负向调节作用机制，揭示Aurora-A激酶在NSCLC发生发展中起到的关键性作用，以及Aurora-A小分子抑制剂在NSCLC中的应用前景，为解释非小细胞肺癌的进展和转移提供有利的分子生物学依据，进而发现新的NSCLC临床分子标记物，以期为NSCLC的诊治提供新的方向以及更加有效的、个体化的治疗靶点。

LBK1基因突变或功能缺失是非小细胞肺癌（NSCLC）致病及进展机理之一，但是其上游调控分子机制目前仍未被阐明。本项目证明Aurora-A通过磷酸化LKB1抑制LKB1/AMPK信号通路，从而增强肿瘤的增殖侵袭及迁移能力：1. 通过划痕、免疫组化染色、MTT、Western blot及transwell技术，明确Aurora-A表达NSCLC发生发展的相关性；2. 通过质粒转染、生物信息学分析，质谱分析、in vitro kinase、冷激酶实验等实验方法，在细胞水平找出Aurora-A磷酸化LKB1的磷酸化位点LKB1-S299，建立并验证“Aurora-A ---- LKB1---- AMPK”的负向调控模式。本项目阐明Aurora-A与LKB1的具体作用机制，为NSCLC的侵袭和转移机制提供新的分子生物学理论；Aurora-A不仅可以作为非小细胞肺癌转移和预后的分子生物学标记物，还可为患野生型LKB1非小细胞肺癌患者的治疗提供新的有效靶点。