Provectors for treatment of ovarian cancer

项目总结 用核酸(如基因或RNAi)来对抗转移性卵巢癌是一种非常有前途的方法 治疗方法。编码促凋亡因子或基因的核酸可杀死肿瘤细胞 可以将前体药物转化为有毒分子的酶。然而，任何基因疗法的成功都是不可避免的 方法取决于能否将基于核酸的效应分子输送到高表达的靶向肿瘤。 特异性和效率，这是一项在很大程度上难以实现的壮举。大多数载体靶向方法都可以 DATE依赖于细胞表面受体在某些亚群的靶癌细胞上过度表达。 不幸的是，没有唯一的细胞表面生物标记物来专门识别肿瘤中的所有细胞。至 克服这一限制，我们建议开发一种可激活蛋白酶的病毒载体平台，我们称之为 PROVECTIONS。原载体只有在被胞外蛋白酶激活后才能传递转基因 在卵巢肿瘤微环境中存在高水平。特别是，ProVectors被设计为检测 基质金属蛋白酶(MMPs)，如MMP2和MMP9的过度表达与卵巢 癌症的进展和死亡。我们的Pro载体技术是基于临床上有前景的腺相关 病毒(AAV)，最近已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构建其转导功能由 MMPs。在原位卵巢癌模型中，Pro载体原型能够显著增加转基因 向肝和脾的非靶向递送减少的肿瘤的递送和表达。此外，在刚刚 单次静脉注射携带HSV-tk基因的转移性卵巢癌小鼠 与对照组相比，使用更昔洛韦的患者有显著更好的治疗效果。拟议的项目将 支持设计和表征具有改进功能的第二代PROVERS，并启用 进一步的活体测试。在具体目标1中，我们将构建一个高效Pro矢量的模块化平台，用于 瞄准转移性卵巢肿瘤。在具体目标2中，我们将通过一个 试管试剂盒。最后，在具体目标3中，我们将测试ProVECTS在临床前的性能 卵巢癌的模型。拟议中的项目，如果成功，将产生一套可激活的蛋白酶 具有改进的性质的前导载体可以靶向并在体内根除转移性卵巢肿瘤。

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.