Provectors for treatment of ovarian cancer

项目摘要 递送核酸（例如基因或RNAi）以对抗转移性卵巢癌是非常有希望的治疗方法。 治疗方法肿瘤细胞可以被编码促凋亡因子或促凋亡因子的核酸杀死。 可以将前药转化为有毒分子的酶。然而，任何基因疗法的成功 该方法取决于将基于核酸的效应分子递送至具有高表达的靶向肿瘤的能力。 具体性和效率，这是一项很难实现的壮举。大多数载体靶向方法 迄今为止，人们依赖于在靶癌细胞的某些亚群上过表达的细胞表面受体。 不幸的是，没有独特的细胞表面生物标志物可以特异性地识别肿瘤中的所有细胞。到 为了克服这一限制，我们建议开发一种蛋白酶激活病毒载体平台，我们称之为 Provectors.前载体不能传递转基因，直到它们被细胞外蛋白酶激活 在卵巢肿瘤微环境中以高水平存在。特别是，Provectors旨在检测 基质金属蛋白酶（MMP-2和MMP-9）的过度表达与卵巢癌的发生有关， 癌症进展和死亡。我们的Provector技术是基于临床上有前途的腺相关 病毒（AAV），最近被批准为欧洲第一个人类基因治疗产品。我们有 关键的试点数据表明，我们有能力建立其转导能力被激活的Provectors MMPs在原位卵巢癌模型中，Provector原型能够显着增加转基因肿瘤的发生。 在肿瘤中的递送和表达，减少了向肝和脾的脱靶递送。此外，在刚刚 单次静脉内注射编码HSV-tk的Provector，治疗携带转移性卵巢肿瘤的小鼠 与对照组相比，更昔洛韦组的治疗效果明显更好。拟议项目将 支持具有改进功能的第二代Provector的设计和表征， 进一步的体内测试。在具体的目标1中，我们将构建一个高效Provector的模块化平台， 靶向转移性卵巢肿瘤。在具体目标2中，我们将通过以下方式表征所开发的Provectors： 一组体外测定。最后，在具体目标3中，我们将在临床前测试Provectors的性能 卵巢癌的模型。该项目如果成功，将产生一套蛋白酶可激活的 具有改进的性质的可在体内靶向和根除转移性卵巢肿瘤的前体。

PROJECT SUMMARY Delivery of nucleic acids (e.g. genes or RNAi) to combat metastatic ovarian cancer is a highly promising therapeutic approach. Tumor cells may be killed by nucleic acids encoding either pro-apoptotic factors or enzymes that can convert prodrugs into toxic molecules. Invariably, however, the success of any gene therapy approach hinges on the ability to deliver the nucleic acid-based effector molecules to target tumors with high specificity and efficiency, a feat that has been largely difficult to achieve. Most vector targeting approaches to date have relied on cell surface receptors overexpressed on some subpopulation of target cancer cells. Unfortunately, there is no unique cell surface biomarker that specifically identifies all cells in a tumor. To overcome this limitation, we propose to develop a platform of protease-activatable viral vectors that we call Provectors. The Provectors cannot deliver transgenes until they become activated by extracellular proteases present at high levels in ovarian tumor microenvironments. In particular, the Provectors are designed to detect matrix metalloproteinases (MMPs), such as MMP-2 and MMP-9, whose overexpression is correlated to ovarian cancer progression and death. Our Provector technology is based on the clinically promising adeno-associated virus (AAV), which has recently been approved as the first human gene therapy product in Europe. We have key pilot data demonstrating our ability to build Provectors whose transduction capabilities are activated by MMPs. In an orthotopic ovarian cancer model, a Provector prototype is able to significantly increase transgene delivery and expression in tumors with decreased off-target delivery to liver and spleen. Furthermore, after just a single intravenous injection of Provector encoding HSV-tk, metastatic ovarian tumor bearing mice treated with ganciclovir had significantly better therapeutic outcomes compared to controls. The proposed project will support the design and characterization of the 2nd generation of Provectors with improved features and enable further in vivo testing. In specific aim 1, we will construct a modular platform of high efficiency Provectors for targeting metastatic ovarian tumors. In specific aim 2, we will characterize the developed Provectors via a panel of in vitro assays. Finally, in specific aim 3, we will test the performance of Provectors in preclinical models of ovarian cancer. The proposed project, if successful, will generate a suite of protease-activatable Provectors with improved properties that can target and eradicate metastatic ovarian tumors in vivo.