Strategies to Enhance Adenoviral Mediated Tumor Killing

描述（由申请人提供）：肺癌是癌症的主要原因 美国男性和女性中只有 13% 的人患有肺癌 癌症存活5年。非小细胞肺癌的支持治疗， 是最常见的形式，中位生存率仅为 4 个月。新 药物组合只能将生存期提高至 8-10 个月。新的发展 因此，治疗方式非常重要。该研究详细介绍于 该提案旨在开发新颖、高效且安全的基因疗法 治疗肺癌的方法。该方法将基于修改 腺病毒基因靶向病毒复制和细胞杀伤肺癌 细胞。细胞周期调节基因如 p53 和 Rb 在 癌细胞和腺病毒感染的细胞。腺病毒基因的缺失 因此，改变细胞周期控制的病毒复制目标可能是 癌细胞。 Elb-55kD 删除病毒已被引入以 p53 为目标 然而，一些报告对这种方法提出了质疑。在 根据该提案，将确定是否具有修饰的Ela基因的腺病毒 无法灭活 Rb 和/或 p300，病毒复制的目标是 癌细胞。为了进一步将病毒复制靶向肺癌细胞， 修饰后的 Ela 基因的转录将被限制在肺细胞中 使用肺特异性启动子。第二个目标的重点是改善 复制腺病毒载体的溶瘤活性。腺病毒 E1b-19kD 蛋白是一种有效的细胞凋亡抑制剂，并且是一种具有以下功能的腺病毒： 该基因被删除，可以更有效地杀死病毒并通过单层传播 肿瘤细胞。因此，E1b-19kD 缺失的影响现在是 在小鼠模型中进行评估。此外，结合病毒的效果 将评估细胞毒性剂的感染。在第三个目标中， 腺病毒载体的溶瘤活性和特异性，结合 使用 E1b-19kD 基因对修饰的 Ela 基因进行转录靶向 将评估删除。小鼠的安全性很难评估 人类腺病毒不能在小鼠细胞中复制的模型。在第四个目标中， 这些腺病毒构建体的安全性将通过测量来评估 新鲜分离的病毒复制、细胞杀伤和细胞凋亡诱导 肺肿瘤细胞。

DESCRIPTION (provided by applicant): Lung cancer is the leading cause of cancer death in American men and women, and only 13 percent of people who develop lung cancer survive 5 years. Supportive care for non-small cell lung cancer, which is the most common form, yields median survival rates of just 4 months. New drug combinations improve survival only to 8-10 months. The development of new treatment modalities is therefore of great importance. The research detailed in this proposal aims to develop novel, highly effective, but safe gene therapy approaches to treat lung cancer. The approach will be based on modifying adenoviral genes to target viral replication and cell killing to lung cancer cells. Cell cycle regulating genes such as p53 and Rb are inactivated both in cancer cells and in adenovirus infected cells. Deletion of the adenoviral genes that alter control of the cell cycle may therefore target viral replication to cancer cells. An Elb-55kD deleted virus has been introduced to target p53 mutant cancer cells, however several reports have questioned this approach. In this proposal, it will be determined if an adenovirus with a modified Ela gene that is unable to inactivate Rb and/or p300, will target viral replication to cancer cells. To further target viral replication to lung cancer cells, transcription of the modified Ela gene will be restricted to lung cells by using lung specific promoters. The focus of the second aim will be improving the oncolytic activity of a replicating adenoviral vector. The adenoviral E1b-19kD protein is a potent inhibitor of apoptosis, and an adenovirus with this gene deleted, more efficiently kills and spreads through a monolayer of tumor cells. The effects of the E1b-19kD deletion will therefore now be evaluated in a mouse model. In addition, the effects of combining viral infection with cytotoxic agents will be evaluated. In the third aim, the oncolytic activity and specificity of an adenoviral vector, that combines transcriptional targeting of the modified Ela gene with an E1b-19kD gene deletion will be evaluated. Safety aspects are difficult to evaluate in a mouse model as human adenoviruses do not replicate in mouse cells. In the fourth aim, the safety of these adenoviral constructs will be evaluating by measurement of viral replication, cell killing and induction of apoptosis in freshly isolated lung tumor cells.