智能响应成像型分子靶向/基因治疗联用纳米给药系统一体化诊疗EGFR突变型肺癌研究

The oncology community has seen a paradigm shift in molecular treatment of non-small cell lung cancer (NSCLC) thanks to the identification of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). However, only the NSCLC patients with specific molecular target could benefit from EGFR-TKIs, and the majority of the treated NSCLC patients develop acquired resistance. The aim of this project is to construct new nanotheranostics which could not only recognize and diagnose EGFR-mutated lung cancer to guide rational use of the EGFR-TKIs, but also exert molecular targeted and gene combination therapeutic effects for overcoming drug resistance and improving efficacy. Based on the previously synthesized chitosan derivatives which were used for gene delivery, the multifunctional chitosan derivatives (CsTE7) will be firstly synthesized by further modification with molecular targeted drug erlotinib and fluorescence controllable cyanine dye Cy7 using “click chemistry”. Secondly, CsTE7/Survivin-targeting shRNA expression vector complex nanoparticles (CsTE7Ns) will be prepared and characterized. Finally, the selective diagnostic ability and molecular targeted/gene combination therapeutic effects of CsTE7Ns will be studied in the wild type and mutated EGFR (including erlotinib sensitive and drug resistant) cancer cells or tumor-bearing mouse models. The mechanisms of CsTE7Ns for selective diagnosis and combination treatment of EGFR-mutated lung cancer will also be studied. The research ideas and the research contents of this project are both new. The results of this project will provide new strategy for improving medication accuracy and efficacy of molecular targeted drugs. The results of this project will also provide new research ideas and methods for individualized lung cancer treatment. We believe this kind of nanotheranostics possess a vast range of application prospect.

以EGFR酪氨酸激酶抑制剂为代表的分子靶向药物在非小细胞肺癌治疗中表现出巨大潜力，但靶向药物仅对具有特定分子靶点的患者有效，且易产生耐药。本项目拟构建集定位诊断和个性化干预于一体的纳米药物，可识别并诊断EGFR突变型肺癌细胞，指导临床合理用药；同时发挥分子靶向/基因联合治疗效果，克服耐药，提高疗效。本项目利用申请人前期工作中用作基因载体的壳聚糖衍生物，采用“点击化学”法进一步合成靶向药物厄洛替尼和荧光可控菁染料Cy7修饰的多功能壳聚糖衍生物，包载干扰凋亡抑制蛋白Survivin的基因药物形成纳米粒并表征其理化性质；在EGFR野生型和突变型（包括厄洛替尼敏感和耐药型）肺癌细胞及荷瘤鼠模型中研究其选择性诊断及分子靶向/基因联合治疗效果和机制。本项目的研究思路和内容新颖，其结果可为提高肿瘤分子靶向药物的用药准确性及有效性提供新策略，同时为肺癌个体化治疗提供新的研究思路和方法，具有重要的应用前景。

分子靶向药物在非小细胞肺癌治疗（NSCLC）中表现出巨大潜力，但其疗效与特定基因突变水平密切相关，且易产生耐药。本项目选用表皮生长因子受体酪氨酸激酶抑制剂（EGFR-TKI）厄洛替尼（Er）和花氰染料Cy7共价偶联到壳聚糖（Cs）上构建自组装纳米载体CE7Ns。CE7Ns中的Er可选择性识别特定NSCLC细胞并利用Cy7分子做出荧光成像诊断，并发挥Cy7的光动力治疗作用，克服Er耐药，提高抗肿瘤效果。在此基础上，进一步通过“点击化学”反应将Er、炔基季铵盐和Cy7连接到Cs骨架上，形成CE7Q纳米材料；将炔基季铵盐连接到Cs骨架上，得到水溶性较好的CQ纳米材料，CQ与CE7Q混合后运载Survivin短发夹RNA（shRNA）的表达质粒（SV）得到CE7Q/CQ/S纳米复合物。CE7Q/CQ/S可特异性识别EGFR突变型NSCLC细胞并进行选择性成像，并通过联合分子靶向/基因/光热治疗协同抗EGFR突变型肺癌并逆转Er耐药。相关研究在国际重要学术刊物上发表标注受本项目资助的高质量SCI论文25篇（其中IF>10的3篇，IF>5的7篇，5>IF>3的10篇），申请相关专利10项，获授权专利4项。共培养研究生4人，其中获国家奖学金1人，获福州大学优秀硕士论文2人。该研究成果对于新型纳米诊疗剂的开发提高抗肿瘤治疗效果及其在肺癌个体化治疗领域中的应用具有重要的参考价值。