Gene-Product Auto-Targeting to Tumor Vessels

描述（由申请人提供）：在肿瘤中靶向基因产物对于全身基因传递非常重要，因为使用最成功的全身肿瘤靶向基因传递技术，只有一部分基因能够成功地传递到肿瘤中。更重要的是，一些基因产物，如IL-12，与肿瘤共定位时比停留在血液或其他器官中更有效，将基因产物靶向肿瘤的一种简单方法是产生并使用编码IL-12和肿瘤靶向微肽的融合基因。出乎意料的是，我们发现没有一种已知的肿瘤靶向肽能提高il -12诱导的抗肿瘤功效。然而，在目前的资助期内，我们发现了一种新的肽VNTANST，当编码IL-12-VNTANST的融合基因被注射到远离肿瘤的肌肉中时，它可以促进IL-12蛋白在肿瘤中的积累。利用基因治疗方法进行DNA递送，并使用融合基因产物IL-12- vntanst进行肿瘤靶向治疗（肿瘤靶向IL-12基因治疗在多种肿瘤模型中显示出抑制肿瘤的巨大潜力）。我们还发现这种靶向肿瘤的IL-12 （IL-12- vntanst）与vimentin结合，vimentin是一种被称为细胞内蛋白的蛋白质，在转移性肿瘤中增加。一个有趣的问题是细胞外IL-12-VNTANST是如何与细胞内蛋白结合的？值得注意的是，我们的初步研究表明，在恶性上皮细胞的细胞膜上发现了波形蛋白。我们在这项更新应用中的目的是确定在一些转移性肿瘤细胞中膜静脉蛋白定位是否增加，从而在与IL-12-VNTANST结合并提高il -12抗肿瘤功效方面发挥重要作用。我们还将研究如何有效地利用这种靶向IL-12基因治疗，利用肿瘤靶向IL-12基因治疗各种器官的膜阳性转移性肿瘤。我们假设肿瘤靶向IL-12- VNTANST基因疗法在治疗膜静脉蛋白阳性转移性肿瘤方面具有很大的潜力。该研究具有创新性，因为它可以明确地证实膜vimentin定位在肿瘤转移和促进拟议的靶向IL-12基因治疗中起关键作用。膜静脉蛋白依赖性的确认也将使我们在未来选择合适的荷瘤患者进行这种治疗，这就是所谓的个性化免疫治疗，是新疗法的一个重要方向，也是我们努力的长期目标。

DESCRIPTION (provided by applicant): Targeting gene product in tumors is very important for systemic gene delivery because only a portion of genes are successfully delivered into tumors by using the most successful systemic tumor-targeted gene delivery technology. More importantly, some gene products such as IL-12 are more effective when co-localized with tumors, compared to staying in blood or other organs One simple approach to targeting gene product into tumors is to generate and use fusion genes encoding IL-12 and tumor-targeted mini-peptide. Unexpectedly, we found that none of the known tumor-targeted peptides boost IL-12-induced anti-tumor efficacy. In the current grant period, however, we discovered the novel peptide VNTANST, which boosts accumulation of IL-12 protein into tumors when a fusion gene encoding IL-12-VNTANST, was administered into muscles distant from the tumors. Using a gene therapy approach for DNA delivery and using a fusion gene product IL-12-VNTANST for tumor-targeting (tumor-targeted IL-12 gene therapy has shown great potential in inhibiting tumors in multiple tumor models. We also revealed that this tumor-targeting IL-12 (IL-12-VNTANST) binds to vimentin, a protein known as an intracellular protein and increased in metastatic tumors. An intriguing question is how the extracellular IL-12-VNTANST binds to an intracellular protein? Significantly, our preliminary study showed that vimentin is found on the cell membrane of malignant epithelial cells. Our objective in this renewal application is to determine whether membrane vimentin localization is increased in some of the metastatic tumor cells and thus has a significant role in binding to IL-12-VNTANST and boosting IL-12-anti-tumor efficacy. We will also examine how to effectively using this targeted IL-12 gene therapy for treating membrane positive metastatic tumors in various organs using tumor-targeted IL-12 gene therapy. We hypothesize that tumor-targeted IL-12- VNTANST gene therapy has a great potential for treating membrane vimentin positive metastatic tumors. The proposed study is innovative because it may definitively confirm that the membrane vimentin localization plays a key role for tumor metastasis and for boosting the proposed targeted IL-12 gene therapy. Confirmation of membrane vimentin dependence would also allow us selecting proper tumor-bearing patient in the future to perform this therapy, which is so called personalized immune therapy, an important direction of novel therapeutics and a long term of goal of our effort.