肺腺鳞癌转分化是导致肺癌恶性进展及其药物耐受的重要因素，我们前期建立肺腺鳞癌转分化的动物模型并发现活性氧自由簇的过度累积会显著促进肺腺鳞癌转分化。但是，肺腺癌细胞如何在活性氧自由簇过度累积的压力下变异和适应并不清楚。本项目将利用肺腺鳞癌转分化动物模型，系统性地分析肺腺鳞癌转分化不同阶段的小鼠肿瘤基因及蛋白质表达谱，揭示肺腺鳞癌转分化过程中肿瘤细胞适应与变异规律，并利用临界理论模型分析鉴定其中的关键节点及其调控网络，利用CRISPR/Cas9介导的动物体内基因敲除技术研究关键节点的功能和作用机制。我们前期已经建立肺腺鳞癌转分化的动物模型、临界理论模型以及CRISPR/Cas9介导的动物体内基因敲除技术，为本项目的顺利实施奠定坚实的基础。本项目将从基因微进化的角度解析肺腺鳞癌转分化过程中细胞变异与适应规律，并建立肺腺鳞癌恶性进展的动态预测模型，为更好地认识肺腺鳞癌的发病分子机制提供帮助。

The transdifferentiation of lung adenocarcinoma (ADC) to squamous cell carcinoma (SCC) is essential for the malignant progression and drug resistance of lung cancer. We have previously established the mouse model for lung ADC-to-SCC transdifferentiation (AST) and found excessive reactive oxygen species (ROS) accumulation significantly promotes this process. However, it remains unknown how lung cancer cells adapt and evolve under the pressure of excessive oxidative stress. Taking advantage of the established AST mouse model, this project aims to provide systematic analyses of gene expression and protein expression profiles from mouse lung tumors from different stage during the AST process and try to decipher the principle of lung cancer cell adaptation and variation. Furthermore, we will utilize the theory model based on dynamical network biomarker (DNB) to identify the key nodes and related regulatory networks during the AST process. Using the CRISPR / Cas9-mediated in vivo gene knockout technique, we will investigate the function and related mechanism for these key nodes and related regulatory network in mouse models and cell lines. In our preliminary data, we have established the animal model of lung AST, the critical theoretical model based on DNB and the CRISPR/Cas9-mediated in vivo gene knockout technology, which lay a solid foundation for the smooth implementation of the project. The project will uncover the microevolution principle for lung cancer cell adaptation and variation during the transdifferentiation process from lung adenocarcinoma to squamous cell carcinoma and establish a dynamic model of forecasting the malignant progression of lung adenosquamous carcinoma, which might provide help for better understanding of the molecular pathogenesis of this deadly disease.