Chemistry of Probes and Therapeutics

7.2.1。核心A.探针和治疗学的化学 核心领导人：保罗·温德 调查人员：劳伦斯·马内特、大卫·奥斯特罗夫 目标1：审查主要项目和特定任务项目的探测设计，包括基于 多肽和COX-2抑制剂，并优化荧光和拉曼标记的结合化学(图 25)。 人们普遍认为，在癌症治疗中，及早发现有助于提高存活率。 胃肠道癌症和癌前病变息肉的检测已得到改进 内窥镜检查，但这种方法可能会漏掉难以观察到的组织和扁平肿瘤。在……里面 此外，在某些情况下，正常组织和癌前组织之间的差异只能在 分子水平。这就需要使用分子探针来可视化组织差异。 温德实验室在药物/探针输送系统的创新和使用方面拥有相当多的专业知识， 包括多肽和探针化学的发展，以及它们的偶联方法 并在细胞和动物中进行评估。这些专业知识将被用于小说的设计和合成 探针共轭，以及必要时合成方法的开发甚至发明。一个 各种连接策略，以使不可释放和可释放的化合物以及 已开发出选择性可释放的偶联物。这些实验室提供了相当多的经验 分子探针的设计、合成和评价，分子探针是分子研究不可缺少的工具 成像策略。 开发用于光学成像的探针的一个重大挑战是将标签粘贴到 侦测。荧光团的选择以及它们如何连接到特定的探针上可以极大地 改变所选择的多肽或小分子的特异性和有用性。我们的目标是解决这个问题 使用基于结构的分子动力学模拟评估分子的优先取向的挑战 探针结合到目标蛋白质上。这个过程是从我们的分子对接方法WE 利用高通量模式选择针对目标蛋白质的小分子(并行 在佛罗里达大学高性能计算中心使用DOCK6进行处理)。 在确定探针与目标蛋白(图25)、溶剂结合的最可能方向之后 选择探针中暴露的原子作为标记的附着点(图25)。实时 先导化合物的自动组合启发式增强，Rachel(Tripos，Inc.)是一种毒品吗 优化包设计用于在自动化的、 组合时尚。我们经常使用雷切尔来添加化学基团，如荧光团，以加入铅 与Kd值在微摩尔范围内结合以增加其比活性的化合物 (图25)。这一过程可以应用于5ROX和大量潜在的荧光团，以最大化 识别保留特异性的优化标记探针的可能性。 目标2：设计下一代治疗药物并开发具有定向递送和 控制释放。 温德实验室在探头的设计、合成和评估方面拥有丰富的经验 能够或增强细胞和组织进入的结合物。已经制定了程序和系统 这使得能够实时量化细胞和转基因动物的摄取。这些研究已经 被转化为药物输送结合物的开发，包括已经 已进入第二阶段人体临床试验。这项工作的很大一部分已经应用于交付过多的 通过分子转运蛋白，最具体但不限于辛精氨酸。这种分子 转运体已被用于输送治疗药物，如紫杉醇、环孢素A、SN-38、雷帕霉素、 多肽、蛋白质、siRNA、质粒DNA、金属、显像剂，甚至磁性颗粒。各种各样的 释放机制已经开发出来。转运体技术与生物可剥离链接器策略 在我们的实验室中开发出了许多应用程序，这些应用程序已经超出了本发明的重点 这是一项非常重要的研究工作，可应用于整个药物输送和偶联化学领域。 随着选择性给药的重要性与日俱增，我们可以运用 以前在我们实验室开发的与药物输送相关的方法，并在此方法上进行扩展以实现目标 对胃肠道癌症和其他疾病的选择性分娩。此应用程序的方方面面 依赖于分子检测和可视化的技术可以通过访问 核心实验室提供设计和合成方面的专业知识。 目标3：与调查人员和FDA合作，首先开发新产品，然后获得批准 可在胃肠道用于成像和治疗的试剂。 新型选择性探针剂和治疗剂的研制 胃肠道癌症旨在最终应用于临床环境。温德实验室有 开发外用八精氨酸-环孢素A类药物的体会 治疗牛皮癣，结合物进入第二阶段人体临床试验。研究还表明， 基于IP、眼部、口腔和肺部药物给药，程序与 拟议的结肠研究涉及到当地的管理。此专业知识可用于支持和促进 根据需要设计、合成和评估新的探针和药物结合物，以实现以下目标 这个项目。

7.2.1. Core A. Chemistry of probes and therapeutics Core Leader: Paul Wender Investigators: Lawrence Marnett, David Ostrov Aim 1: Review probe designs for the major projects and task-specific projects including those based on peptides and cox-2 inhibitors, and optimize conjugation chemistries for fluorescent and Raman tags (Fig 25). It is generally accepted that early detection leads to improved survival rates in the treatment of cancers. Detection of cancers and precancerous polyps in the gastrointestinal tract has been improved with endoscopy procedures, but this approach can miss difficult to observed tissue and flat neoplasias. In addition for some situations the difference between normal and precancerous tissue is only detectable at the molecular level. This necessitates the use of molecular probes for visualization of tissue differences. The Wender lab has considerable expertise in the innovation and use of drug/probe delivery systems, which includes the development of peptide and probe chemistry, as well as methods for their conjugation and evaluation in cells and in animals. This expertise will be employed in the design and synthesis of novel probe conjugates, as well as the development and even invention of synthetic methods as necessary. A variety of linkage strategies to make both non-releasable and releasable compounds as well as selectively releasable conjugates has been developed. The laboratories offer considerable experience in the design, synthesis, and evaluation of molecular probes that are indispensable tools for molecular imaging strategies. A significant challenge in the development of probes for optical imaging is in the attachment of labels for detection. The selection of fluorophores .and how they are conjugated to specific probes can drastically alter the specificity and usefulness of selected peptides or small molecules. We aim to address this challenge by using structure-based molecular dynamic simulations to assess the preferred orientation of the probe bound to the target protein. This process is adapted from the molecular docking method we utilize in the high-throughput mode to select small molecules specific for target proteins (by parallel processing using DOCK6 at the University of Florida High Performance Computing Center). After determining the most likely orientation of the probe bound to the target protein (Fig. 25), solvent exposed atoms in the probe are selected as points of attachment for the label (Fig. 25). Real-time Automated Combinatorial Heuristic Enhancement of Lead compounds, RACHEL (Tripos, Inc.) is a drug optimization package designed to optimize weak binding lead compounds in an automated, combinatorial fashion. We routinely use RACHEL to add chemical groups, such as fluorophores, to lead compounds that bind with Kd values in the micromolar range in order to increase their specific activities (Fig. 25). This process can be applied to 5ROX and a large number of potential fluorophores to maximize the likelihood of identifying optimized labeled probes that retain specificity. Aim 2: Design next generation therapeutic agents and develop conjugates with directed delivery and controlled release. The Wender lab has considerable experience with the design, synthesis and evaluation of probe conjugates that enable or enhance cell and tissue entry. Procedures and systems have been developed that allow for quantification of uptake in real time in cells and in transgenic animals. These studies have been translated into the development of conjugates for drug delivery, including studies that have progressed to phase II human clinical trials. Much of this work has been applied the delivery of a plethora of therapeutics via a molecular transporter, most specifically but not limited to octaarginine. This molecular transporter has been used to deliver therapeutic agents such as taxol, cyclosporine A, SN-38, rapamycin, peptides, proteins, siRNA, plasmid DMA, metals, imaging agents and even magnetic particles. A variety of release mechanisms have been developed. The transporter technology and bioreleasable linker strategies developed in our laboratories have numerous applications which transcend the focus of this particular effort and could have applications for the entire field of drug delivery as well as conjugation chemistry. With the growing importance of selectivity in the delivery of therapeutic agents, we can apply methods previously developed in our lab related to drug delivery and expand on this methodology to realize the goal of selective delivery to gastrointestinal cancers, as well as other diseases. All facets of this application that rely on molecular detection and visualization can be facilitated and enhanced through access to design and synthetic expertise available in the core laboratory. Aim 3: Work with investigators and the FDA to first develop and then get approval for new reagents that can be used in the Gl tract for imaging and therapy. Development of new selective probe and therapeutic agents for the detection and treatment of gastrointestinal cancers is intended for eventual application in a clinical setting. The Wender lab has experience in this area with the development of octaarginine-cyclosporine A agents for the topical treatment of psoriasis, with conjugates advancing into Phase II human clinical trials. Studies have also been advanced based on IP, ocular, buccal, and lung drug administration, procedures that not unlike the proposed colon studies involve local administration. This expertise is available to enable and facilitate the design, synthesis, and evaluation of new probes and drug conjugates as needed to achieve the aims of the program.