Improving the in Vivo Delivery and Antitumor Efficacy of Antisense Drugs

摘要 基于核苷酸的药物，如反义(ASO)，代表了一类基本的药物类型，这些药物 对那些所谓的小分子和抗体“无法下药”的靶标特别有用。然而，有一个 ASO药物翻译的最大障碍之一是体内递送能力差。存在几个障碍，以实现 阻止ASO有效地到达体内的靶细胞：快速的肾脏清除，核酸酶降解， 非特异性吸收，穿透血管内皮细胞和扩散到血管外组织的效率低。 在这个方案中，我的目标是应用多肽靶向和纳米材料技术来增强递送 ASO对实体瘤的治疗效果。 为了防止肾滤过和核酸酶降解，ASO将被包裹在多孔硅中 纳米粒子(PSiNPs)。PSiNPs是可生物降解的，在体内毒性很低或没有毒性。更重要的是， PSiNPs可能对ASO和其他寡核苷酸具有最高的负载效率。最重要的 我们建议的目标是帮助ASO优先在肿瘤中蓄积，并穿透肿瘤血管 去接触那些远离血液循环的靶细胞。我们的肿瘤穿透性CENDR多肽是 在实现这一目标的为数不多的可用工具中。通过与肿瘤血管上的某些受体结合，cendr 多肽激活了一个活跃的跨肿瘤血管的运输过程，以及广泛的货物类型， 包括pSiNPs。在目标1中，我将合成cendR功能化的、负载ASO的pSiNPs。此外 通过化学表征，我还将在体外验证该系统的细胞进入和基因沉默效果。 在目的2中，我将对其体内毒性、药代动力学和组织分布进行评价。在目标3中， Cendr-pSiNP-ASO的基因调控和抑瘤效果将通过动物肿瘤来确定 模特们。我提议的研究具有改善肿瘤递送和抗肿瘤疗效的巨大潜力 ASO，并加速ASO原型药物进入临床的过渡。

Abstract Nucleotide-based drugs, such as antisense (ASO), represent an essential class of drug types that are particularly useful for those so-called “undruggable” targets by small molecules and antibodies. However, one of the biggest hurdles in the translation of ASO drugs is the poor in vivo delivery. Several barriers exist to prevent ASOs from efficiently reaching their target cells in vivo: rapid renal clearance, nuclease degradation, unspecific absorption, low efficiency to penetrate across the endothelium and spread in extravascular tissue. In this proposal, I aim to apply the technologies of peptide targeting and nanomaterial to enhance the delivery efficiency of ASOs into solid tumors. To prevent renal filtration and nuclease degradation, ASOs will be encapsulated within porous silicon nanoparticles (pSiNPs). pSiNPs are biodegradable and have low or no toxicity in vivo. More importantly, pSiNPs have likely the highest loading efficiency for ASOs and other oligonucleotides. The most important goal of our proposal is to help ASOs preferentially accumulate in tumors, and penetrate across tumor vessels to access to those target cells far away from the circulation. Our tumor-penetrating CendR peptides are one of the few tools available to achieve this goal. By engaging with certain receptor on the tumor vessels, CendR peptides activate an active transport process across tumor vessels along with a wide range of cargo types, including pSiNPs. In the Aim 1, I will synthesize CendR-functionalized, ASO-loaded pSiNPs. Besides chemical characterization, I will also validate the cell entry and gene-silencing efficacy of this system in vitro. In the Aim 2, I will evaluate the in vivo toxicity, pharmacokinetics and tissue distribution. In the Aim 3, the gene modulation and tumor-inhibitory efficacy of CendR-pSiNP-ASO will be determined using animal tumor models. My proposed studies hold great potential for improving the tumor delivery and antitumor efficacy of ASOs, and accelerating the transition of prototype ASO drugs into the clinic.