MYLK在非小细胞肺癌淋巴结转移中的作用及分子机制研究

Lymphatic metastasis is one of the main factors for the lung cancer poor prognosis. MYLK (Myosin light chain kinase)is acytoskeletal protein that has been reported it to play the role in the proliferation and metastasis of a variety of tumors, but its role in lymphatic metastasis of lung cancer and its mechanism has not been elucidated.Preliminary work showed that the level of MYLK mRNA and protein expression in tumor tissues of patients withlung cancer lymphatic metastasis was significantly higher than that in the group without metastasis.By means of non labeling quantitative proteomics and phosphorylated polypeptide segment analysis ,it was found that MYLK could regulate several enzymes involved in carbohydrate metabolism, suggesting that MYLK may play an important role in lymph node metastasis of lung cancer and the possible mechanism was related to glucose metabolism.This Project aims to study the molecular mechanism of metastasis of lung cancer lymph node of MYLK regulation, by using the co-culture condition and Nude mice transplantation tumor model. Observing the metastatic phenotype of A549 and H460 cells of lung cancer cell line by over expression and silencing of MYLK. And screening and verifying the changes of genes and proteins in the model, finding out the MYLK specific regulation of the cytokines and downstream signaling pathways, to prove that MYLK is a key molecule in non small cell lung cancer lymph node metastasis, contribute to the inhibition of lung cancer metastasis of new therapeutic targets.

淋巴结转移是导致肺癌不良预后的一个主要因素。肌球蛋白轻链激酶（MYLK）是一种细胞骨架蛋白，已报道它在多种肿瘤的增殖和转移中发挥作用，但它在肺癌淋巴转移中的作用及其机制尚未阐明。前期工作中我们发现在肺癌淋巴转移患者肿瘤组织中MYLK mRNA、蛋白表达显著高于未转移组，且利用非标记定量蛋白质组学和磷酸化多肽段分析发现MYLK对糖代谢信号转导通路多个代谢酶有调控作用，这提示MYLK可能在肺癌淋巴结转移中发挥重要作用，其机制可能和糖代谢相关。本项目拟采用条件共培养和原位转移模型研究MYLK调控肺癌淋巴结转移的作用及其分子机制。首先，利用过表达和干扰MYLK明确肺癌细胞株A549和H460细胞转移能力的变化，以及验证明确MYLK 具体调控的下游信号通路，揭示MYLK调控非小细胞肺癌淋巴结转移的分子机制，这将为开发非小细胞肺癌淋巴结转移的新靶点奠定理论基础。

肺癌是中国和全球高发、并且具有极高致死率的的恶性肿瘤。本课题组以前期研究为基础，使用生物信息学的方法对GEO数据库中非小细胞肺癌的芯片数据进行挖掘，并通过实验验证的潜在促进肺癌转移的关键因子，推测MYLK通过介导微环境中各种细胞因子而调控下游肺癌转移相关的信号通路。通过定量蛋白质组学以及分子生物学技术，发现和筛选了MYLK下游信号通路中对肿瘤发生和发展起关键作用的一系列重要蛋白质。同时，运用先进的CanPatrol MCTC富集技术和原位杂交分析技术，从NSCLC患者分离并对CTCs分型。然后，我们探索了CTCs亚群与NSCLC临床分期之间的关系，发现在间质细胞中Ki一67高表达可能与twist高表达在促进肿瘤的增殖、发展过程中存在相互协同作用。本研究对阐释肺癌的发展，转移及预后的机制有着重要意义。