Oncolytic adenovector-mediated TRAIL gene therapy for cancers

描述（由申请人提供）：肿瘤坏死因子相关凋亡诱导配体（TRAIL）和溶瘤病毒载体最近已被广泛研究用于癌症治疗。然而，临床前和临床研究表明，这两种药物的临床应用受到其弱抗癌活性或可能的全身毒性的阻碍。因此，最大化其抗癌活性并最小化其全身毒性的策略对于这些药物在癌症治疗中的成功至关重要。本提案的目的是确定表达TRAIL基因的肿瘤特异性复制能力（溶瘤）腺病毒载体用于治疗癌症的有效性和安全性。要测试的假设是，病毒疗法和TRAIL基因疗法整合到单一药剂中将增强其体内转导效率和肿瘤诱导能力，并且从人端粒酶逆转录酶（hTERT）启动子表达TRAIL和E1 A基因的溶瘤腺载体将病毒疗法和TRAIL基因疗法靶向癌症，破坏肿瘤组织但保留正常组织。我们的初步研究表明，将肿瘤坏死因子相关凋亡诱导配体基因纳入溶瘤腺病毒载体增强病毒复制和溶瘤在癌细胞中，无论他们是敏感或耐药的肿瘤坏死因子相关凋亡诱导配体基因，在体外和体内，在正常人成纤维细胞中具有最小的复制活性和细胞毒性作用。在nu/nu小鼠中，表达TRAIL的溶瘤腺病毒载体的病灶内给药消除了从人非小细胞肺癌细胞系建立的所有皮下异种移植肿瘤，导致长期无肿瘤存活。为了进一步验证这一假设，我们将确定最佳的腺病毒载体系统的hTERT-TRAIL交付人类和同系叙利亚仓鼠肿瘤通过评估的治疗和副作用的hTERT-TRAIL交付E1缺失载体，溶瘤载体，和纤维修饰的溶瘤载体在体外和体内。我们还将确定腺病毒载体引发的免疫应答是否会对抗肿瘤活性或副作用产生任何影响。最后，我们将确定表达TRAIL的溶瘤载体在免疫功能低下和免疫活性动物中建立的人和叙利亚仓鼠同系转移模型中的抗肿瘤活性。完成所提出的研究将使我们能够确定递送hTERT-TRAIL的最佳方法并制定治疗转移的策略。这些临床前研究的结果也将为未来肿瘤坏死因子相关凋亡诱导配体（TRAIL）治疗和溶瘤病毒治疗的整合提供坚实的科学基础，并可能为癌症治疗带来新的治疗药物。

DESCRIPTION (provided by applicant): The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and oncolytic virus vectors have recently been investigated extensively for cancer therapy. However, preclinical and clinical studies have revealed that the clinical application of these two agents is hampered either by their weak anticancer activity or by their possible systemic toxicity. Therefore, strategies to maximize their anticancer activity and minimize their systemic toxicity are essential to the success of these agents in the treatment of cancers. The goal of this proposal is to determine the efficacy and safety of a tumor-specific replication-competent (oncolytic) adenovector expressing the TRAIL gene for the treatment of cancer. The hypothesis to be tested is that integration of virotherapy and TRAIL gene therapy into a single agent will enhance its in vivo transduction efficiency and apoptosis-induction capacity and that an oncolytic adenovector expressing both the TRAIL and E1A genes from the human telomerase reverse transcriptase (hTERT) promoter will target both virotherapy and TRAIL gene therapy to cancer, destroying tumor tissue but sparing normal tissue. Our preliminary studies showed that incorporating the TRAIL gene into an oncolytic adenovector enhanced viral replication and oncolysis in cancer cells, whether they were susceptible or resistant to the TRAIL gene, both in vitro and in vivo, with minimal replication activity and cytotoxic effects in normal human fibroblasts. Intralesional administration of the TRAIL-expressing oncolytic adenovector eliminated all subcutaneous xenograft tumors established from a human non-small cell lung cancer cell line in nu/nu mice, resulting in long-term tumor-free survival. To further test the hypothesis, we will determine the optimal adenovector systems for the delivery of hTERT-TRAIL to human and syngeneic Syrian hamster tumors by evaluating the therapeutic and side effects of hTERT-TRAIL delivered by an E1-deleted vector, an oncolytic vector, and a fiber-modified oncolytic vector in vitro and in vivo. We will also determine whether an immune response triggered by an adenovector will have any effect on either antitumor activity or side effects. Finally, we will determine the antitumor activity of the TRAIL-expressing oncolytic vector in both human and Syrian hamster syngeneic metastatic models established in both immunocompromised and immunocompetent animals. Completing the proposed studies will allow us to determine the optimal methods for delivery of hTERT- TRAIL and develop strategies for the treatment of metastasis. The results of these preclinical studies will also provide a solid scientific basis for future integration of TRAIL therapy and oncolytic virotherapy and may lead to new therapeutic agents for cancer therapy.