Heat Induced Suicide Gene Therapy for H and N Cancer

H 和 N 癌症的热诱导自杀基因治疗

• 批准号: 6867829
• 负责人: Buck E. Rogers
• 金额: $ 6万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-29 至 2006-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6867829
• 关键词: athymic mouse; combination cancer therapy; cytotoxicity; ganciclovir; gene expression; gene therapy; genetic promoter element; head /neck neoplasm; heat shock proteins; ionizing radiation; mutant; neoplasm /cancer thermotherapy; neoplastic cell; nonhuman therapy evaluation; positron emission tomography; squamous cell carcinoma; thymidine kinase; time resolved data; transfection /expression vector; xenotransplantation

DESCRIPTION (provided by applicant): Approximately 28,200 new cases of head and neck squamous cell carcinoma (HNSCC) will be diagnosed in 2004 with an estimated 7,200 deaths occurring. Clearly, additional local therapy is warranted to improve outcome. To determine the effectiveness of additional local treatment, a molecular imaging approach is proposed using a modified viral vector for both diagnostic and treatment purposes. This proposal will use molecular imaging to evaluate transgene expression in mice bearing HNSCC xenografts following administration of the viral vector. It is well established that hyperthermia enhances the cytotoxic effects of external beam ionizing radiation (IR). HNSCC has become a target of gene therapy and hyperthermic intervention strategies due to its anatomic accessibility. The enzyme herpes simplex virus type 1 thymidine kinase (HSV1-TK) in combination with ganciclovir (GCV) has been shown in vitro and in vivo to exert a cytotoxic effect after gene transfer of TK. A mutant version of TK (mTK) that enhances the cytotoxic effects of GCV and can be imaged by positron-emission tomography (PET) using positron-emitting nuclesoside analogs has been constructed. Therefore, improved imaging and therapy of HNSCC should be accomplished by gene transfer of mTK. However, one of the problems associated with gene transfer approaches has been the non-target expression of transgene. In this regard, we have constructed an adenovirus (AdHSmTK) encoding mTK under control of the inducible heat shock 70b (HS) promoter. This vector will only allow expression of mTK after exposure to heat. Using ultrasound technology we can deliver focused heat to xenografts that parallels clinical delivery. The specific aims are: 1.) Characterize the time course and level of expression of mTK in HNSCC cells after infection with AdHSmTK and determine the cytotoxicity after exposure to GCV and IR; 2.) Characterize the time course and level of expression of mTK in nude mice bearing HNSCC xenografts after infection with AdHSmTK with microPET imaging following exposure to heat. We hypothesize that the combination of gene therapy with hyperthermia and IR will have a greater impact than either alone or combination of two of the modalities in vitro and that the use of molecular imaging to optimize the system in vivo will lead to a rational treatment protocol combining these modalities in the future.

描述（由申请人提供）：将在2004年诊断出大约28,200例头颈鳞状细胞癌（HNSCC）新病例，估计发生7200例死亡。显然，有必要进行其他局部疗法以改善结果。为了确定其他局部治疗的有效性，提出了一种分子成像方法，使用改良的病毒载体来诊断和治疗目的。该建议将使用分子成像来评估施用病毒载体后带有HNSCC异种移植的小鼠中的转基因表达。众所周知，高温增强外束电离辐射（IR）的细胞毒性作用。 HNSCC由于其解剖学可及性而成为基因治疗和高温干预策略的靶标。单纯疱疹病毒1型胸苷激酶（HSV1-TK）与Ganciclovir（GCV）结合使用，在体外和体内显示出在TK基因转移后在体外和体内发挥细胞毒性作用。 TK（MTK）的突变版可以增强GCV的细胞毒性作用，并可以使用正电子发射断层扫描（PET）使用正电子发射核苷类似物来成像。因此，应通过MTK的基因转移来完成改进的HNSCC成像和治疗。但是，与基因转移方法相关的问题之一是转基因的非目标表达。在这方面，我们构建了一个编码MTK的腺病毒（ADHSMTK），该MTK控制着诱导热冲击70b（HS）启动子。该矢量只能在暴露于热量后表达MTK。使用超声技术，我们可以将聚焦热量输送到与临床传递相似的异种移植物。具体目的是：1。）表征用ADHSMTK感染HNSCC细胞中MTK的时间过程和表达水平，并确定暴露于GCV和IR后的细胞毒性； 2.）表征在暴露于热量后用ADHSMTK感染ADHSMTK后，带有HNSCC异种移植物的裸鼠中MTK的时间过程和表达水平。我们假设，基因治疗与高温和IR的结合将比单独使用或两种体外方式的组合更大，并且使用分子成像在体内优化系统将导致一种合理的治疗方案，从而结合了这些方式。