Optimizing RNA nanoparticles size and shape for enhancing cancer targeting and treatment

项目摘要 RNA纳米技术在过去几年中发展迅速。这种纳米技术包括 将多个功能模块整合到一个纳米颗粒中，其中的支架，配体， 治疗剂和调节剂可以主要或完全由RNA组成。我们构建了RNA 不同尺寸、形状和化学计量的纳米颗粒，显示出高化学和热力学稳定性 并证明了它们具有不同功能基团的能力，如siRNA、miRNA、核酶、药物， 和癌症靶向RNA适体。所有功能模块均保留其真正的折叠和独立性 这些功能用于特异性细胞结合、基因沉默和体内癌症靶向。全身注射后， 在荷瘤小鼠中，RNA纳米颗粒特异性和强烈地结合异种移植和转移性肿瘤， 给药后3-4小时，在健康的重要器官和组织中几乎没有蓄积。的RNA 纳米颗粒是无毒的，并显示出有利的生物分布和药代动力学特征。 我们的长期目标是促进RNA纳米颗粒作为新一代药物用于治疗 癌症在诊所该项目的短期目标是表征RNA纳米颗粒在细胞内的行为。 体外和体内，目的是提高特异性细胞靶向、内化和细胞内 运输、良好的生物分布而不截留在肝脏中、内体逃逸和肿瘤消退。 这些研究基于三个中心假设：（1）细胞内运输途径和内体 逃逸对于有效的癌症治疗至关重要;（2）RNA的生物分布和药理学特征 纳米颗粒是形状和大小依赖性的;和，（3）由RNA纳米颗粒引起的免疫应答是 高度依赖于RNA序列、化学修饰、大小、形状和化学计量。解决我们 目标，我们将（1）系统地剖析RNA纳米颗粒所采取的细胞内途径，并增强 （2）检查药代动力学（PK）;药效学（PD）;和 RNA纳米颗粒的生物分布，目的是以最小的累积增强癌症靶向， 健康器官;以及（3）评估RNA纳米颗粒的免疫应答以最小化非特异性副作用 效果，以及开发方法来刺激免疫系统，通过纳入免疫刺激 用于癌症免疫治疗的RNA纳米颗粒。完成这些临床前研究后，我们 我将鉴定出几种具有优化形状、大小和化学计量的RNA纳米颗粒， 良好的安全性和高疗效，符合FDA新药研究指南 开始临床试验。

PROJECT SUMMARY RNA nanotechnology has progressed rapidly during the past several years. This nanotechnology includes the integration of multiple functional modules into one nanoparticle, of which the scaffolds, ligands, therapeutics, and regulators can be composed mainly or exclusively of RNA. We have constructed RNA nanoparticles of diverse size, shape, and stoichiometry displaying high chemical and thermodynamic stability and demonstrated their ability to harbor different functional groups, such as siRNA, miRNA, ribozyme, drug, and cancer targeting RNA aptamer. All functional modules retain their authentic folding and independent functionalities for specific cell binding, gene silencing, and cancer targeting in vivo. Upon systemic injection in tumor bearing mice, RNA nanoparticles bind to xenograft and metastatic tumors specifically and strongly with little to no accumulation in healthy vital organs and tissues 3-4 hours post-administration. The RNA nanoparticles are non-toxic and display favorable biodistribution and pharmacokinetic profiles. Our long-term goal is to promote RNA nanoparticles as a new generation of drug for the treatment of cancers in the clinic. The short-term goal of this project is to characterize the behavior of RNA nanoparticles in vitro and in vivo, with an aim to improve the efficiency for specific cell targeting, internalization and intracellular trafficking, favorable biodistribution without entrapment in liver, endosome escape, and tumor regression. These studies are based on three central hypotheses: (1) intracellular trafficking pathways and endosome escape are critical for effective cancer therapy; (2) biodistribution and pharmacological profiles of RNA nanoparticles are shape and size dependent; and, (3) immune responses elicited by RNA nanoparticles are highly dependent on RNA sequence, chemical modifications, size, shape, and stoichiometry. To address our goals, we will (1) systemically dissect the intracellular pathways taken by RNA nanoparticles and enhance their endosome escape capabilities; (2) inspect the pharmacokinetics (PK); pharmacodynamics (PD); and biodistribution of RNA nanoparticles with the goal of enhancing cancer targeting with minimal accumulation in healthy organs; and, (3) evaluate the immune responses of RNA nanoparticles to minimize non-specific side effects, as well as develop methods to stimulate the immune system by incorporating immuno-stimulatory modules to RNA nanoparticles for cancer immunotherapy. Upon completion of these pre-clinical studies, we will have identified several RNA nanoparticles with optimized shape, size, and stoichiometry displaying favorable safety profiles and high therapeutic efficacy to comply with FDA Investigational New Drug guidelines for initiating clinical trials.