Enhancement of Tumor-Targeted Transgene Expression

描述(申请人提供)：在这项申请中，长期目标是开发一种有效的肿瘤靶向脂合物，用于胰腺癌的系统治疗，胰腺癌是人类所有恶性肿瘤中预后最差的一种。我们以前的研究表明，利用肿瘤靶向的脂质体基因递送系统，通过修复p53可以使癌细胞对放射/化疗增敏。对于wtp53基因和其他基因的传递，我们开发了一种配体，肿瘤靶向脂质体复合体，一种纳米颗粒传递系统(NDS)。这不仅抑制了肿瘤的生长和/或提高了存活率，而且当与放射或化疗相结合时，还能在小鼠癌症模型中完全、长期地消除一些肿瘤。为了进一步提高NDS的转染率，最近我们设计了在复合体中包含一种对pH敏感的阳离子HK肽(组氨酸寡聚氨酸)，以促进DNA从内体释放。我们的NDS的优势之一是它可以广泛应用于多种肿瘤类型。因此，在本应用程序中，我们将重点介绍Panca。本STTRI方案的主要目的是优化这种修饰的复合体，并评价其体外转导效率和体内靶向胰腺癌的能力。这种新型的NDS在有效的肿瘤靶向传递和抗肿瘤疗效方面的潜力的评估可能是繁琐的，当仅仅基于生物测定时，特别是关于生产治疗剂的产品释放标准。因此，开发使用物理参数表征NDS的方法将是至关重要的。与NIST的John Dagata博士合作，我们建议使用先进的成像分析，包括原子力显微镜、电场力显微镜和相位成像来表征NDS，并将这些物理分析的结果与观察到的复合体的生物效应相关联。这将使我们能够利用我们的努力进行开创性的尝试，弥合两种不同技术之间的差距，从而开发新的工程方法来表征、设计和改进治疗输送系统。此外，建立新的技术来评估NDS的物理特征也将有助于为这些生物疗法制定更精确的产品释放标准。

DESCRIPTION (provided by applicant): In this application, the long-term goal is the development of an effective tumor-targeting lipoplex for systemic treatment of pancreatic cancer (PanCa), which has one of the worst prognosis of all human malignancies. Our previous studies indicate that cancer cells can be sensitized to radiation/chemotherapy via p53 restoration ,using a tumor-targeting liposomal gene delivery system. For the delivery of the wtp53 gene, as well as other genes, we have developed a ligand, tumor-targeting liposome complex, a nanoparticle delivery system (NDS). This resulted not only in tumor growth inhibition and/or increased survival, but also, in complete, long-term elimination of some tumors in mouse models of cancer when combined with either radiation or chemotherapy. To further achieve improvement in transfection efficiency of our NDS, recently we have designed the inclusion of a pH sensitive cationic HK peptide (histidylated oligolysine) in the complex to enhance DNA release from the endosome. One of the advantages of our NDS is that it can be broadly employed for numerous tumor types. Thus, in this application we will focus on PanCa. The major aims of this STTR I proposal are to optimize this modified complex and evaluate its transfection efficiency in vitro and its in vivo targeting ability for PanCa tumors. The assessment of this novel NDS with respect to its potential for efficient tumor-targeting delivery and antitumor efficacy can be cumbersome when based solely on biological assays, particularly in regards to product release criteria for production of therapeutic agents. Consequently, the development of methods for characterizing NDS using physical parameters would be essential. Joining forces with Dr. John Dagata at NIST, we propose to use advanced imaging analysis including atomic force microscopy, electric force microscopy, and phase imaging to characterize the NDS and correlate the results of these physical analyses with the observed biological effects of the complex. This will allow us to leverage our efforts in a pioneering attempt to bridge the gap between two distinct technologies, thus developing new engineering methodologies to characterize, design and improve therapeutic delivery systems. In addition, establishing new technologies to assess the physical characteristics of NDS will also aid in developing more precise product release criteria for these biological therapeutics.