Targeting Pancreatic Cancer Using Peptide Chemistry: From Bench to Bedside

描述（由申请人提供）：胰腺腺癌（PCA）几乎是一种致命的疾病。此外，由于在将癌变的分子机制转化为可行的治疗方法方面存在重大差距，常规治疗通常会失败。许多有丝分裂生长因子及其受体的过表达，特别是IGF-1R和EGFR的过表达，已在晚期胰腺癌患者中观察到高频率。一些研究已经完成，试图了解导致IGF-1R和egfr介导的信号通路，但受体过表达的分子机制尚不清楚。在我们发表的和初步的研究中，我们已经定义了IGF-1R和EGFR在PCA中过表达的独特机制。我们的数据还定义了RGS/PDZ结合蛋白GIPC的一种新的调控作用，它通过两种不同的机制控制IGF-1R和EGFR的表达。此外，我们还发现表达GIPC shRNA的胰腺癌细胞生长明显慢于亲本细胞，其转移能力受到限制。我们最近发表的研究结果也鼓励我们提出一种利用纳米技术改进给药方法的靶向治疗方法。综上所述，这些观察结果使我们假设GIPC功能失活可以被利用来抑制IGF-1R和EGFR过表达，这对PCA具有重要的临床意义。为了验证我们的假设，我们提出了四个目标。目的1将研究GIPC对PCA细胞中IGF-1R和EGFR过表达的调控作用的分子机制。目标2将开发化学发现平台，用于鉴定新型肽基GIPC配体。在Aim 3中，我们将重点研究GIPC肽基配体的生化表征和细胞探针的开发。目标4将侧重于基于纳米技术的靶向治疗的发展。我们将在体外合成和表征抗IGF-1R抗体、附着在金纳米颗粒表面的GIPC肽（IGF-1R和EGFR抑制剂）与吉西他滨或不含吉西他滨的不同组合。在本目标的后半部分，我们将从前面的目标中推断出知识和试剂，以模拟人类疾病的正异性胰腺癌动物模型。我们将研究纳米金缀合药物在体内的疗效，以了解多靶点联合药物在PCA进展和转移中的重要性。此外，我们将确定有效药物的药代动力学，药效学，生物分布和生物毒性，这将导致我们在不久的将来进行临床试验。总的来说，我们高度合作提出的实验将确定目前没有治疗方法的胰腺腺癌治疗干预的特定靶点。

DESCRIPTION (provided by applicant): Pancreatic adenocarcinoma (PCA) is an almost invariably fatal disease. Furthermore, conventional treatment generally fails because of a significant gap in translating the molecular mechanisms of carcinogenesis into feasible therapeutics. Overexpression of many mitogenic growth factors and their receptors, in particular the overexpression of IGF-1R and EGFR, has been observed with a high frequency in patients with advanced pancreatic cancer. Several studies have been completed in an attempt to understand the pathways that lead to IGF-1R and EGFR-mediated signaling, but the molecular mechanism of receptor overexpression remains unclear. In our published as well as preliminary studies, we have defined a unique mechanism of IGF-1R and EGFR overexpression in PCA. Our data also define a novel regulatory role of GIPC, a RGS/PDZ binding protein, which controls both IGF-1R and EGFR expression by two distinct mechanisms. Moreover, we have also shown that pancreatic cancer cells expressed shRNA of GIPC grow significantly slower than that of parental cells, and their metastasis capabilities are restricted. Our recent published results have also encouraged us to propose a targeted therapeutic approach using nanotechnology to improve drug delivery methods. Taken together, these observations have led us to hypothesize that inactivation of GIPC function can be exploited to inhibit IGF-1R and EGFR overexpression in a targeted manner that would have important clinical implications in PCA. To test our hypothesis, we have proposed four aims. Aim 1 will examine the molecular mechanism of the regulatory role of GIPC on IGF-1R and EGFR overexpression in PCA cells. Aim 2 will develop chemical discovery platforms for identifying novel peptide-based ligands for GIPC. In Aim 3, we will focus on biochemical characterization and cellular probe development of peptide-based ligands for GIPC. Aim 4 will focus on the development of nanotechnology-based targeted therapeutics. We will synthesize and characterize in vitro the different combinations of anti-IGF-1R antibody, GIPC peptides (IGF-1R and EGFR inhibitors) attached onto the surface of gold nanoparticles with or without gemcitabine. In the later part of this aim, we will extrapolate the knowledge and reagents from the previous aims to the animal model of orthotropic pancreatic cancer that can mimic human diseases. We will examine the in vivo efficacy of the nanogold conjugated drugs in vivo seeking to understand the importance of multi-targeted, combination drugs in PCA progression and metastasis. Furthermore, we will determine pharmacokinetics, pharmacodynamics, bio-distribution, and bio-toxicity of the effective drugs that will lead us toward clinical trials in the near future. Overall, our highly collaborative proposed experiments will identify specific targets for therapeutic interventions for pancreatic adenocarcinoma where no current therapy is available.