新型VSVMP和IL-12双基因制剂靶向治疗膀胱癌的实验研究

Currently, targeted gene therapy of cancer is one of the research focuses. In the past research, our research group found that the plasmid expressing vesicular stomatitis virus matrix protein (VSVMP) can induce apoptosis of cancer cells, showing promising application in cancer therapy（nine papers including ACS Nano 2010 and FASEB J 2008）. In this project, to improve the anticancer effect of VSVMP gene, we colon VSVMP gene and IL-12 gene in the same eukaryotic expression vector, in which IL-12 gene can activiate the anticancer immune response. Moreover, we use a targeted and controlled gene therapy technology (the selective expression of gene in cancer cells is regulated by the telomerase reverse transcriptase promoter, and the targeted delivery of gene into cancer cells is achieved by a novel degradable polyethyleneimine-derived nanoparticle）. Now, we have already got a new targeted gene formulation for VSVMP and IL-12 daul gene plasmid, and preliminarily found that it could efficently inhibit the growth of the orthotopic bladder cancer xenografts and did not cause significant side effect. In our future work, we plan to deeply study the target efficiency, anticancer effect and machanism of this novel VSVMP and IL-2 daul gene formulation against bladder cancer, with the goal of demonstrating a new idea for designing targeted cancer gene therapy protocol and providing a potential candidate for bladder cancer therapy.

肿瘤靶向基因治疗是当前国际上的研究热点。我们课题组研究发现编码水泡口炎病毒基质蛋白（VSVMP）的基因可诱导肿瘤细胞凋亡，在肿瘤治疗中有潜在应用（ACS Nano 2010, IF=12; FASEB J 2008, IF=5.5;等9篇文章）。本课题中，为进一步提高VSVMP基因治疗肿瘤的作用，我们将激发抗肿瘤免疫的IL-12基因与VSVMP基因共表达在真核载体上，采用一种靶向可控基因治疗技术（端粒酶逆转录酶启动子调控基因在肿瘤细胞选择性表达，新型可降解聚乙烯亚胺纳米粒靶向导入基因到肿瘤细胞），构建了一种新型的VSVMP和IL-12双基因靶向制剂，并初步发现膀胱灌注该制剂可显著抑制膀胱癌原位移植瘤的生长且未引起明显毒副作用。下一步，我们将深入研究VSVMP和IL-12双基因制剂对膀胱癌的靶向性和治疗膀胱癌的作用及机理，为肿瘤靶向基因治疗研究提供新思路，为膀胱癌治疗提供潜在新选择。

基因治疗为肿瘤治疗提供了新手段，本课题围绕肿瘤治疗的重大需求，结合肿瘤基因治疗前沿，开展非病毒基因治疗药物通过诱导肿瘤细胞凋亡及激发抗肿瘤免疫等机制治疗肿瘤的研究。首先，设计、构建了基于肝素-PEI纳米粒和iDPP纳米粒的新型非病毒基因导入系统，系统地研究了其理化性质及生物学效应，发现具有可降解、毒性低、可靶向肿瘤等特点，在肿瘤基因治疗中有较好的应用前景，为肿瘤基因治疗研究提供了技术支撑。其次，构建了同时编码VSVMP和IL12的双基因质粒，发现纳米粒介导的基因药物在肿瘤细胞同时表达VSVMP和IL12具有协同抗肿瘤作用，其抗肿瘤免疫反应明显增强，可有效抑制肿瘤及预防复发。进一步，系统地研究了VSVMP基因制剂治疗膀胱癌的作用及机制，建立了多种膀胱癌动物模型，发现局部应用VSVMP基因制剂可有效抑制膀胱癌，经膀胱灌注后可有效转染膀胱癌细胞及抑制膀胱癌原位移植瘤的生长，疗效优于阳性对照品，且不会引起明显的毒副作用，具有较好的成药性，为膀胱癌治疗提供了潜在新选择，另外还发现对恶性黑色素瘤等多种肿瘤都具有明显的抗肿瘤作用，揭示了在肿瘤治疗中的潜力。本课题的开展为肿瘤基因治疗研究提供了新线索，为膀胱癌治疗提供了潜在新选择，相关研究成果已发表SCI论文15余篇，申请发明专利1项，培养研究生3名，较好的完成了课题目标。