Exosomal drug formulations

描述(申请人提供)：在美国，每年死于肺癌的人数(160,340人)比前列腺癌、乳腺癌和结肠癌的总和还要多。最常见的肺癌类型是非小细胞肺癌(NSCLC)，占所有肺癌的75%。令人遗憾的是，所有被诊断为非小细胞肺癌的患者中，85%最终在5年内死于这种疾病，原因是微转移和复发。目前，超过1200万癌症幸存者居住在美国，其中只有3.3%(约40万人)是肺癌幸存者。迫切需要改进有效的癌症治疗方法，这不仅可以使肺癌幸存者受益，也可以使其他癌症类型的幸存者受益。该项目将开发一种“平台技术” 对于外切体制剂，使用牛乳衍生的外切体，同时具有亲脂性和亲水性药物。具体地说，我们将制备标准化疗(化疗)药物紫杉醇(PAC)和具有化学预防和治疗潜力的天然化合物FERA(WFA)的外周制剂，并检测它们预防和治疗癌症的能力。我们将把重点放在肺癌上，并将寻求提高这些药物的口服生物利用度，并减少它们所需的剂量。尽管剂量很高，但天然化合物往往存在口服生物利用度问题。另一方面，静脉注射化疗(化疗)药物会伴随着不受欢迎的血液水平大幅上升。由于固有的局限性，几十年来在脂质体和聚合物纳米颗粒配方方面的工作只提供了少数几种有效的药物用于临床。在这项应用中，将优化具有强大治疗活性的外切体分离和外切体制剂，并确定其治疗效果和潜在的毒性。牛乳来源的外切体的生产将是可扩展的、经济可行的，并且具有很高的成本效益。胞外给药方法有可能通过挑战现有的涉及大剂量有毒化疗药物的范例来改变目前的癌症治疗实践。我们假设口服PAC和WFA的外切体制剂将比各自的游离药物(没有外切素制剂)更有效，并且该制剂将减少所需的有效剂量，从而最小化或消除毒性。其具体目的是(1)优化从牛乳中分离/纯化外切体，最大限度地提高PAC和WFA的载药量，并确定外切体制剂的稳定性；以及(2)确定PAC和WFA的外切体制剂在细胞培养和裸鼠异种移植模型中对人肺癌细胞的有效性，并确定其在小鼠模型中的潜在毒性。未来的工作将优化和确定PAC和WFA以及包括siRNAs在内的其他化合物的纳米喷雾干燥外切体制剂的有效性，确定其长期稳定性，并使用裸鼠原位移植瘤模型测试PAC和WFA的单独和联合制剂对药物敏感、耐药和转移性肺癌细胞的作用。

DESCRIPTION (provided by applicant): More people in the U.S. (160,340 per year) die of lung cancer than of prostate, breast, and colon cancer combined. The most common type of lung cancer, non-small-cell lung cancer (NSCLC), accounts for 75% of all lung cancers. Regrettably, 85% of all patients diagnosed with NSCLC eventually die of the disease within 5 years, due to micro-metastasis and relapse. Currently, over 12 million cancer survivors reside in the U.S., of which only 3.3% (about 400,000) are lung cancer survivors. Improved methods in effective cancer treatment are urgently needed and could greatly benefit not only lung cancer survivors, but also those of other cancer types. This project will develop a "platform technology" for exosome formulations, using bovine-milk-derived exosomes, of both lipophilic and hydrophilic drugs. Specifically, we will prepare exosome formulations of a standard chemotherapeutic (chemo) drug, paclitaxel (PAC), and a natural compound with chemopreventive and therapeutic potential, withaferin A (WFA), and examine their ability to prevent and treat cancer. We will focus on lung cancer and will seek to enhance the oral bioavailability of these drugs and reduce their required doses. Natural compounds often suffer from oral bioavailability issues, despite high doses. On the other hand, chemotherapeutic (chemo) drugs given intravenously are accompanied by undesirable large spikes in blood levels. Decades of work with liposomal and polymeric nanoparticle formulations have rendered only a handful of effective drugs for use in the clinics due to inherent limitations. In this application e will optimize exosome isolation and exosome formulations with potent therapeutic activity, and determine their therapeutic efficacy and potential toxicity. Production of the bovine milk-derived exosomes will be scalable, economically feasible, and highly cost effective. The exosomal drug delivery approach has the potential to change the current practice of cancer treatment by challenging the existing paradigm involving high doses of toxic chemo drugs. We hypothesize that exosome formulations of PAC and WFA administered orally will be more effective than respective free drugs (without exosome formulation), and that the formulation will reduce the required effective dose, thus minimizing or eliminating toxicity. The specific aims are to (1) optimize exosome isolation/purification from bovine milk, maximize drug loading of PAC and WFA, and determine stability of the exosome formulations; and (2) determine the efficacy of exosome formulations of PAC and WFA, in cell culture and in a nude mouse xenograft model, against human lung cancer cells, and also determine potential toxicities in a mouse model. Future efforts will optimize and determine the efficacy of nano spray-dried exosome formulations of PAC and WFA and other compounds, including siRNAs, determine their long-term stability, test formulations of PAC and WFA, both individually and in combination, against drug-sensitive, drug-resistant and metastatic lung cancer cells, using orthotopic tumor xenograft nude mouse models.