Image-guided TRAIL-enhanced CAR T-cell immunotherapy

项目摘要 已经显示癌细胞对肿瘤坏死因子α相关的凋亡刺激敏感， 凋亡诱导配体（TRAIL），而正常细胞表现出非常小的反应。TRAIL被证明是 作为单一药剂具有活性并与某些化疗剂表现出协同活性，或 放疗，导致肿瘤明显消退或完全缓解。越来越多的证据表明 在活化的T淋巴细胞表面上表达的膜结合的TRAIL可以增强T细胞效应因子， 功能和增强T细胞杀肿瘤活性。通过基因工程改造原代T细胞的能力 在肿瘤免疫和癌症治疗方面具有很好的应用前景。T细胞的转导 编码嵌合抗原受体的基因使T细胞能够识别抗原， 免疫原性或被免疫系统忽略。此外，基因工程表达的 治疗性配体（例如，TRAIL）通过T细胞可以有效地增加它们的杀肿瘤活性。新战略 正在开发对基于TRAIL的免疫疗法的肿瘤致敏和对TRAIL抗性的调节 有些可以转移到诊所。我们的中心主题和假设是，T- 细胞导致肿瘤细胞凋亡增加，并且放射和/或化学疗法积极影响 TRAIL介导的肿瘤细胞凋亡在T细胞过继性免疫治疗中的作用， 增强T细胞肿瘤靶向和效应子功能的方法。 在这项应用中，我们提出开发和测试一种新的治疗诊断方法，以增加肿瘤细胞凋亡， 使用嵌合抗原过表达TRAIL的具有异质性PSMA水平的前列腺癌模型 CAR受体（CAR）移植的PSMA特异性T细胞。我们将评估膜结合型与分泌型 PSMA特异性T细胞表达的TRAIL形式对它们杀死PSMA阳性和阴性靶标的能力的影响。 我们将确定放疗/化疗诱导的TRAIL耐药肿瘤细胞的“致敏”是否 与提高的T细胞杀肿瘤功能相关。最终，我们将评估可行性和敏感性 PET成像监测PSMA特异性T细胞活化和TRAIL治疗有效载荷递送至 肿瘤这些过程将使用多报告基因和常规成像进行监测，通过评估T- 细胞肿瘤靶向和激活以及肿瘤反应。 我们的建议补充了正在进行的临床研究，在MSK和其他癌症中心，探索新的 旨在增强T细胞效应功能和改善治疗反应的策略。结果将 提供临床前支持和理由，以便在前列腺患者中走向临床应用， 其他正在接受基因修饰T细胞免疫治疗的癌症。 !

PROJECT SUMMARY Cancer cells have been shown to be sensitive to apoptotic stimulus of tumor necrosis factor α-related apoptosis-inducing ligand (TRAIL), whereas normal cells showed very little response. TRAIL was shown to be active as a single agent and exhibited synergistic activity with certain chemotherapeutic agents or radiotherapy, causing marked regression or complete remission of tumors. There is increasing evidence that membrane-bound TRAIL expressed on the surface of activated T-lymphocytes can enhance T-cell effector function and augment T-cell tumoricidal activity. The ability to genetically engineer primary T-cells creates new and highly promising prospects for tumor immunity and cancer treatment. The transduction of T-cells with genes encoding chimeric antigen receptors enables T-cell recognition of antigens that are either poorly immunogenic or ignored by the immune system. In addition, the genetically engineered expression of therapeutic ligands (e.g. TRAIL) by T-cells can potently increase their tumoricidal activity. New strategies for tumor sensitization to TRAIL-based immunotherapies and modulation of TRAIL resistance are being developed and some can be translated to the clinic. Our central theme and hypothesis is that TRAIL overexpression by T- cells results in augmented apoptosis in tumor cells and that radiation and/or chemotherapy positively affect TRAIL-mediated tumor apoptosis during T-cell adoptive immunotherapy and can be used as a synergistic approach to enhance T-cell tumor targeting and effector function. In this application we propose to develop and test a novel theranostic approach to augment tumor apoptosis in a prostate cancer model with heterogeneous PSMA levels using TRAIL overexpression by chimeric antigen receptor (CAR)-grafted PSMA-specific T-cells. We will assess the effect of membrane-bound vs. secretable forms of TRAIL expressed by PSMA-specific T-cells on their ability to kill PSMA-positive and -negative targets. We will determine whether radiation/chemotherapy-induced “sensitization” of TRAIL-resistant tumor cells correlates with an improved T-cell tumoricidal function. Ultimately, we will assess the feasibility and sensitivity of PET imaging to monitor PSMA-specific T-cell activation and delivery of TRAIL therapeutic payloads to the tumor. These processes will be monitored using multi-reporter gene and conventional imaging by assessing T- cell tumor targeting and activation as well as tumor response. Our proposal complements on-going clinical studies at MSK and other cancer centers by exploring new strategies designed to enhance T-cell effector function and improve treatment response. The results will provide preclinical support and justification to move toward clinical application in patients with prostate and other cancers undergoing immunotherapy with genetically modified T-cells. !