Transductionally Redirected /Transcriptionally Restricte

转导重定向/转录限制

• 批准号: 7039881
• 负责人: Harvey R. Herschman
• 金额: $ 14.62万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-05-01 至 2010-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7039881
• 关键词: Adenoviridae; bioimaging /biomedical imaging; bioluminescence; colorectal neoplasms; epidermal growth factor; gene targeting; genetic transcription; genetic transduction; genetically modified animals; laboratory mouse; liver neoplasms; neoplasm /cancer therapy; nonhuman therapy evaluation; prostaglandin endoperoxide synthase; virus receptors

Adenovirus vectors are among the most popular vehicles for cancer gene therapy protocols. However, adenovirus infect cells via the Coxsackie and Adenovirus Receptor, which is often more extensively expressed on normal cells then on tumors. We utilized bioluminescent imaging following systemic Ad.CMVfLuc administration to monitor adenovirus transductional "untargeting" and "retargeting" by sCAREGF. sCAR-EGF is a bi-specific retargeting molecule containing the soluble portion of CAR linked to epidermal growth factor. Noninvasive optical imaging demonstrates that systemically injected [Ad.CMVfLuc] [sCAR-EGF] complexes have reduced ability to infect liver, but can infect EGF receptor-positive xenografts. COX-2 is not expressed in most normal tissues, but is overexpressed in many tumors. We used noninvasive optical imaging to examine fLuc expression following intratumoral injection of Ad.COX2fLuc (an adenovirus expressing luciferase from the COX-2 promoter). No expression occurs in liver. In contrast, expression occurs in COX-2 positive tumors. Colorectal cancer (CRC) is a leading cause of cancer death. CRC frequently metastasizes to liver. CRC liver metastases often over-express both carcinoembryonic antigen (CEA) and COX-2. We will combine our experience - both with transductional "untargeting" and "retargeting", and with restricted COX-2 gene expression - to develop effective therapies for CRC hepatic metastases. We will establish xenograft CRC models of liver metastasis. We will create Ad.COX2.fLucTK.COX2, an adenovirus that expresses a fusion protein containing both firefly luciferase and HSV1-thymidine kinase (fLucTK). CRC tumor-restricted fLucTK expression will result from regulation by both the COX-2 promoter and the COX-2 mRNA 3' untranslated region. Transductional liver untargeting and Ad.COX2.fLuTK.COX2 transductional retargeting to CRC xenograft metastases will be optimized with sCAR-f-alphaCEA, a recombinant molecule containing soluble CAR, the phage T4 fibritin trimerization domain and a single-chain anti-CEA antibody. Combined sCAR-f-alphaCEA transductional liver untargeting, transductional tumor retargeting and COX-2 restricted expression should optimize fLucTK expression in CRC hepatic metastases. HSV1-TK/ganciclovir therapy should then effectively eradicate CRC metastases, with minimal side effects. We will employ bioluminescent imaging to monitor restricted fLucTK expression, bioluminescent imaging from xenografts marked with Renilla luciferase and 124I-antiCEA minibody/microPET imaging to monitor tumor burden during HSV1- TK/GCV therapy, and FDG and FLT/microPET to monitor early therapeutic responses. Our goal is to optimize this therapeutic protocol for CRC hepatic metastases, in apreclinical model of human disease.

腺病毒载体是癌症基因治疗方案最受欢迎的车辆之一。然而，腺病毒通过coxsackie和腺病毒受体感染细胞，通常在正常细胞上更广泛地表达在正常细胞上，然后在肿瘤上表达。我们使用系统性AD.CMVFLUC给药后利用生物发光成像来监测ScareGF的腺病毒trand依的转换“未靶向”和“重新定位”。 Scar-EGF是一种双特异性的重新定位分子，该分子包含与表皮生长因子相关的汽车的可溶部分。非侵入性光学成像表明，全身注射的[AD.CMVFLUC] [SCAR-EGF]复合物具有降低的感染肝脏的能力，但可以感染EGF受体阳性异种移植物。 COX-2在大多数正常组织中均未表达，但在许多肿瘤中都过表达。我们使用了无创的 光学成像以检查肿瘤内注射AD.COX2FLUC后的FLUC表达（A 腺病毒从COX-2启动子表达荧光素酶）。肝脏中没有表达。相反，表达发生在COX-2阳性肿瘤中。结直肠癌（CRC）是癌症死亡的主要原因。 CRC经常转移到肝脏。 CRC肝转移通常过表达癌脑抗原（CEA）和COX-2。我们将结合我们的经验 - 既有带有的“不靶向”和“重新定位”，以及受限的COX -2基因 表达 - 开发有效的CRC肝转移疗法。我们将建立肝转移的异种移植CRC模型。我们将创建AD.COX2.FLUCTK.COX2，一种腺病毒，该腺病毒表达含有萤火虫荧光素酶和HSV1-胰岛素激酶（波动）的融合蛋白。 CRC肿瘤限制的波动表达将是由COX-2启动子和COX-2 mRNA 3'未翻译区域的调节所致。转导肝脏不靶向和AD.COX2.FLUTK.COX2转置转置至CRC异种移植转移酶将通过Scar-F-AlphaCea（一种可溶性汽车，含有噬菌体T4纤维蛋白三元化结构域的重组分子）进行优化。疤痕 - α-alpphacea跨传感性肝脏不靶向，跨传输肿瘤重新定位和COX-2限制 表达应优化CRC肝转移中的波动表达。然后，HSV1-TK/Ganciclovir疗法应有效地消除CRC转移，并具有最小的副作用。我们将采用生物发光成像来监测有限的波动表达，带有Renilla Luciferase标记的异种移植物和124i-Antivalea minibody/MicroPET成像的生物发光成像，以监测HSV1-TK/GCV治疗期间的肿瘤负担，以及FDG和FDG和FLT/FLT/MICROPET以监测早期治疗症状。我们的目标是在人类疾病的上行模型中优化CRC肝转移的这种治疗方案。