非小细胞肺癌EGFR联合肿瘤微环境靶向抑制的多模态分子影像学研究

Lung cancer is the current worldwide No.1 malignance with highest morbidity and mortality. How to improve the therapeutic effects of epidermal growth factor receptor (EGFR) targeted therapy on the non small cell lung cancer (NSCLC) patients is a significant problem in clinical treatment. The variation of the tumor microenvironment which is characterized by the infiltration of tumor associated macrophages (TAMs) and massive angiogenesis has a crucial effect on the initial, progression, metastasis, treatment and prognosis of NSCLC. However, there were very little literatures about the related research on in vivo monitoring of the interaction between EGFR expression on NSCLC cells and the microenvironment regulation. The data of our previous projects demonstrated that the near infrared fluorescence imaging (NIRFI) combined with 19 fluorine-1 hydrogen magnetic resonance (19F-1H MR) molecular imaging could be used to in vivo monitor the expression variation of EGFR and angiogenesis in a variety of tumors and to achieve therapeutic effects evaluation qualitatively and quantitatively. Our current research proposed an innovative hypothesis that molecular imaging could be used to in vivo evaluate the regulation effect on EGFR targeted treatment by tumor microenvironment in NSCLC. Three different types of NSCLC nude mice models will be used to investigate the feasibility of achieving multimodality molecular imaging (e.g. NIRFI, 19F-1H MR and T2*mapping) of the EGFR expression on the NSCLC cells, the TAMs amount and the integrin avb3 expression of the angiogenesis in the same nude mice models, with three different kinds of specific probes. Potential beneficial xenografts models with suitable biomarkers overexpression could be screened and selected to receive combined targeted intervention on tumor cells EGFR with/without TAMs and integrin-avb3 targeted inhibition, respectively. The therapeutic effects of this hypothesis and a novel prodrug would be accessed and confirmed by in vitro biology, in vivo molecular imaging and ex vivo histological methods. This research is a proof of concept of the proposal with ultimate aim to establish a new beneficial patients population screening strategy for the personalized treatment of NSCLC based on multimodality molecular imaging, which could improve the therapeutic effect of NSCLC patients and promote the development of new anti-cancer drugs for NSCLC.

肺癌是全球发病率和致死率最高的肿瘤。如何改善非小细胞肺癌表皮生长因子受体（EGFR）靶向治疗疗效是临床面临的难题。以肿瘤相关巨噬细胞浸润和新生血管生成为主要特征的微环境变化对肺癌发展、转移、治疗及预后都有至关重要的影响，在体监测肺癌细胞与微环境相互作用的研究目前鲜有报道。我们前期研究证实近红外荧光成像结合19氟-1氢MR分子成像可以在体定性定量地监测多种肿瘤中EGFR和新生血管的表达变化并实现在体疗效评估。本项目首次提出“分子成像在体监测肺癌微环境对EGFR靶向治疗调控”的假设，通过三种特异性探针靶向肺癌细胞EGFR、肿瘤相关巨噬细胞和新生血管整合素，进行近红外荧光/19氟-1氢/T2*MR多模态分子成像，筛选荷瘤裸鼠进行肿瘤细胞与微环境联合靶向干预，通过体外、在体和离体方法验证该假设及新型前体药物的疗效。以期建立基于分子成像的肺癌个体化靶向治疗新策略，改善肺癌治疗疗效，推动抗癌新药研发。

肺癌在全球范围和中国都是发病率和致死率最高的肿瘤，其中80%为非小细胞肺癌（NSCLC）。如何改善NSCLC表皮生长因子受体（EGFR）靶向治疗疗效是临床面临的重要难题。以肿瘤相关巨噬细胞浸润、肿瘤新生血管生成、肿瘤免疫T细胞浸润为主要特征的肿瘤异质性微环境变化对NSCLC的发展、转移、治疗及预后都有至关重要的影响，因此，本项目旨在利用多模态分子成像技术在体监测肺癌细胞EGFR表达与肿瘤微环境相互作用。本项目建立三种对EGFR阻断敏感性不同的非小细胞肺癌小鼠模型。构建四种特异性分子探针：新生血管integrin-αvβ3靶向性分子成像探针αvβ3-PFOB NP，EGFR近红外荧光成像探针EGF-IRDye® 800CW，肿瘤免疫T细胞表面特异性受体OX40靶向性探针64Cu-DOTA -antiOX40Ab，肿瘤相关巨噬细胞磁共振纳米探针超小超顺磁性纳米铁纳米粒子（USPIO），开展近红外荧光分子成像、1氢-19氟双核磁共振成像、PET-CT和T2*加权映射磁共振成像研究。定量化分析图像所反映的肿瘤细胞EGFR、肿瘤活化免疫T细胞、肿瘤相关巨噬细胞TAMs及肿瘤新生血管integrin-αvβ3表达水平。成像后，进行图像后处理分析，明确EGF-IRDye® 800CW、αvβ3-PFOB纳米粒子、64Cu-antiOX40和USPIO在活体动物内分布、肿瘤摄取情况；评价在体定量分子成像肿瘤细胞与肿瘤微环境TAMs、肿瘤活化T细胞、肿瘤新生血管整合素-αvβ3的可行性。 并通过体外、在体和离体方法验证进一步阐明长链非编码RNA 00857（LINC00857）在非小细胞肺癌中对吉非替尼产生耐药性的重要作用。证明了LINC00857表达在获得性吉非替尼的肺癌组织和细胞中显著上调,通过ceRNA作用机制调节，调节myc/ NF-κB途径。表明LINC00857对非小细胞肺癌耐药的发生具有重要意义，是一种潜在的耐药性生物标志物和治疗手段。