Anti-vascular and cytotoxic nanoparticle formulations for ovarian cancer therapy

卵巢癌（OC）是女性生殖系统所有癌症中死亡率最高的， 过去四十年来，结果没有改变。今年，将有超过20，000名妇女被诊断为 在美国，超过14，000名妇女将死于这种疾病。以铂为基础的治疗是 OC患者的主要治疗选择，最终，全身毒性限制了给药剂量， 限制了它的有效性。为了克服这一治疗障碍，替代的给药途径已经被发现。 已经寻求并且包括实际上困难的腹膜内（IP）注射，并且最近，新兴的 铂（II）化疗与肿瘤血管靶向药物联合策略。的首要目标 本研究旨在开发一种基于纳米颗粒（NP）的治疗方法，用于靶向递送高剂量Pt（II）和 血管破坏剂直接作用于癌细胞和内皮，以提高治疗效果。作为证据- 原则上，我们选择考布他汀CA 4作为血管靶向剂。我们的建议探讨了一个 第二代，缓释聚合物NP平台，具有聚（乳酸-乙醇酸共聚物）（PLGA）酸核 包封Pt（II）和CA 4。NP的涂层由稳定NP的RGDFFF肽组成， 同时通过其RGD部分作为αvβ3整联蛋白的靶向配体。PLGA是FDA批准的 并且所述肽的氨基酸具有一般公认安全（GRAS）状态。NP完全 生物降解。Pt（II）和CA 4的包封将降低全身毒性，并使我们能够探索使用 比目前可行的剂量更高。当NP在肿瘤组织中积累时，通过 增强的渗透性和保留（EPR）效应，细胞NPs摄取将通过受体- 介导的内吞作用。Pt（II）和CA_4对癌细胞的细胞毒活性的影响以及 肿瘤的脉管系统，将通过治疗结果来测量。一小部分近红外线 荧光团（NIRF）将被纳入NP的涂层，使非侵入性光学成像。的 治疗和诊断特征的组合将使NP转变为“治疗诊断”平台。体外 研究将包括评估靶向癌细胞的纳米粒子，其生物活性和与 免疫系统.体内研究将集中于评估NPs的药理学参数、肿瘤生物学参数、肿瘤生物学参数和肿瘤生物学参数。 靶向、耐受性以及最后的治疗效果。将采用体外和体内联合研究 显微镜，免疫化学和组织学，以确定最佳的NP为基础的治疗方案， 治疗效果可与目前临床上使用的免费药物常规相媲美。因此，拟议的具体目标 为： 目的1：合成并表征用于靶向、可视化和治疗的RGDFFF包被的NP平台 卵巢癌目的2：检测CA 4-NPs和Pt-NPs的体外靶向性和治疗潜力。 目标3： 通过体内成像研究临床前OC小鼠模型中NP的生物分布和靶向“捕获”。 目的4：进行治疗研究，其中将CA 4-NP和Pt-NP应用于临床前OC小鼠模型。

Ovarian cancer (OC) has the highest mortality rate of all cancers of the female reproductive system and outcomes have not changed over the past four decades. This year, over 20,000 women will be diagnosed with OC in the United States more than 14,000 women will die from this disease. Platinum-based therapy is the main therapeutic option for OC patients and ultimately, systemic toxicity limits the dosage given and this, in part, limits its effectiveness. To overcome this therapeutic roadblock, alternative routes of administration have been sought and include the practically difficult intraperitoneal (IP) injection, and more recently, the emerging strategy of combining Pt (II) chemotherapy with tumor vasculature-targeting agents. The overarching goal of this study is to develop a nanoparticle (NP)-based therapy for targeted delivery of high dose Pt (II) and a vascular disrupting agent directly to cancer cells and endothelium, to enhance treatment outcomes. As proof- of-principle, we have chosen combretastatin CA4 as the vascular targeting agent. Our proposal explores a second generation, slow releasing polymer NP platform, with poly(lactic-co-glycolic) (PLGA) acid core encapsulating Pt (II) and CA4. The NP’s coating is comprised of a RGDFFF peptide that stabilizes the NP and simultaneously serves as a targeting ligand to αvβ3 integrin via its RGD moiety. The PLGA is FDA-approved and amino acids of the peptide have Generally Regarded As Safe (GRAS) status. The NP is completely biodegradable. Encapsulation of Pt (II) and CA4 will reduce systemic toxicity and allow us to explore the use of effectively higher dosages than currently feasible. Upon the NP’s accumulation in the tumor interstitium, via enhanced permeability and retention (EPR) effects, the cellular NPs uptake will be enhanced via receptor- mediated endocytosis. The effect of the cytotoxic activity of Pt (II) and CA4 towards cancer cells and the tumor’s vasculature, will be measured through therapeutic outcomes. A small percentage of near infrared fluorophore (NIRF) will be incorporated into the NP’s coating to enable noninvasive optical imaging. The combination of therapeutic and diagnostic features will transform the NP into a “theranostic” platform. In vitro studies will include evaluation of NPs targeting to cancer cells, their biological activity, and compatibility with the immune system. In vivo studies will focus on the assessment of NPs pharmacologic parameters, tumor targeting, tolerability, and, finally, therapeutic efficacy. Combined in vitro and in vivo studies will employ microscopy, immunochemistry, and histology, to define the best NP-based treatment regimen resulting in therapeutic outcomes rivaling free drug routines currently used in the clinic. Thus, the proposed specific aims are: Aim 1: Synthesize and characterize an RGDFFF-coated NP platform for targeting, visualizing and treating ovarian cancer. Aim 2: Test targeting efficacy and therapeutic potential of CA4-NPs and Pt-NPs in vitro. Aim 3: Study the biodistribution and targeted ‘trapping’ of NPs in a preclinical OC mouse model via in vivo imaging. Aim 4: Conduct a therapy study wherein CA4-NPs and Pt-NPs, are applied to a preclinical OC mouse model.