Ovarian selective Adenoviral vector for gene therapy of ovarian cancer

用于卵巢癌基因治疗的卵巢选择性腺病毒载体

• 批准号: 6230168
• 负责人: Steven Mark Albelda
• 金额: $ 3.37万
• 依托单位: FOX CHASE CANCER CENTER
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-30 至 2004-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6230168
• 关键词: Adenoviridae; ganciclovir; gene therapy; genetic promoter element; human tissue; laboratory mouse; laboratory rat; method development; neoplasm /cancer therapy; ovary neoplasms; transfection /expression vector; virus replication

DESCRIPTION: (Applicant's Description) New treatments for ovarian cancer are clearly needed. One novel approach under active preclinical and clinical evaluation is gene therapy. Strategies being investigated include use of replication incompetent retroviruses or adenoviruses (AD) to deliver suicide genes such as herpes simplex virus (HSV) thymidine kinase (tk) to activate ganciclovir (GCV) into a cytotoxic drug. One major limitation discovered in an ongoing phase I trial for malignant mesothelioma at the University of Pennsylvania is poor depth of penetration of ADHSV tk into the tumor after intracavitary delivery. A promising approach to overcome this problem is to use replication-competent adenoviruses. When such viruses infect cells and replicate, it causes cell lysis. In addition, active virus is released to infect other tumor cells. By coupling this mechanism of enhanced killing and infection with the ability to activate GCV, we hypothesize that anti-tumor efficacy will be enhanced. However, the delivery of such replication competent viruses causes some safety concerns. To address this issue, a virus conditionally replicative in tumor cells will be constructed. Success would result in a clinical gene therapy trial. Based on the recent discovery at FCCC of a promotor which shows specificity of function in human ovarian cancer, the goal of this proposal is to construct such vectors and preclinically evaluate their efficacy and safety by accomplishing the following specific aims: Specific Aim 1. Develop and evaluate a replication-competent adenoviral vector expressing HSVtk. This will be accomplished by developing and testing a replicating adenoviral vector containing the HSVtk suicide gene. In a first series of experiments (proof of principal), we will study a fully replicative virus containing the HSVtk gene inserted into the E3 region in ovarian tumor models. This will begin to allow us to understand the dynamics of viral replication vs delivery of GCV. Specific Aim 2. Develop and evaluate a replication-competent adenoviral vector expressing HSVtk that will only replicate in ovarian cancer cells. This will be accomplished by developing Ad mutants that replicate selectively in ovarian tumors using the "U3" promoter developed by Dr. Hamilton and his group. These vectors will be made by disrupting the normal Ad E1a promoter region and inserting the ovarian cancer-selective promoter into this region. Since replication is dependent on early production of E1 proteins, viral replication will be limited to those cells in which the tumor specific promoter is active.

描述：（申请人的描述）显然需要卵巢癌的新治疗方法。 基因治疗是一种正在积极进行临床前和临床评估的新方法。 正在研究的策略包括使用复制缺陷型逆转录病毒或腺病毒（AD）来递送自杀基因，如单纯疱疹病毒（HSV）胸苷激酶（tk），以将更昔洛韦（GCV）活化成细胞毒性药物。 在宾夕法尼亚大学正在进行的恶性间皮瘤I期试验中发现的一个主要局限性是腔内递送后ADHSV tk渗透到肿瘤中的深度差。 一个有希望的方法来克服这个问题是使用复制能力的腺病毒。 当这些病毒感染细胞并复制时，它会导致细胞溶解。 此外，释放活性病毒以感染其他肿瘤细胞。 通过将这种增强的杀伤和感染机制与激活GCV的能力相结合，我们假设抗肿瘤功效将得到增强。 然而，这种复制能力的病毒的递送引起一些安全性问题。 为了解决这个问题，将构建在肿瘤细胞中有条件复制的病毒。 成功将导致临床基因治疗试验。 基于最近在FCCC中发现的在人卵巢癌中显示功能特异性的启动子，本提案的目标是构建这样的载体，并通过实现以下特定目标来临床前评估它们的功效和安全性： 开发和评估表达HSVtk的可复制腺病毒载体。 这将通过开发和测试含有HSVtk自杀基因的复制型腺病毒载体来实现。 在第一系列的实验（原理证明）中，我们将研究一种完全复制的病毒，该病毒含有插入卵巢肿瘤模型E3区的HSVtk基因。 这将使我们开始了解病毒复制与GCV递送的动力学。具体目标2。 开发和评估一种仅在卵巢癌细胞中复制的表达HSVtk的可复制腺病毒载体。 这将通过使用汉密尔顿博士和他的小组开发的“U3”启动子开发在卵巢肿瘤中选择性复制的Ad突变体来实现。 这些载体将通过破坏正常的Ad E1a启动子区域并将卵巢癌选择性启动子插入该区域来制备。 由于复制依赖于E1蛋白的早期产生，因此病毒复制将限于肿瘤特异性启动子有活性的那些细胞。