Defining the roles of PPARgamma and TGFbeta in regulating NECTIN4 and resistance to NECTIN4-targeting therapies

项目摘要 此K 08应用程序的目标是为UCSF医学讲师Jonathan Chou博士提供 他将需要成为一个独立资助的实验室调查员的技能。周博士建议澄清 NECTIN 4的调节机制，新批准的抗体-药物缀合物（ADC）的靶点， 转移性尿路上皮癌称为enfortumab vedotin（EV），并使用PDX确定耐药机制 和转移性活检样本。这项提议建立在周博士最近的工作基础上，该工作表明，NECTIN 4 表达在膀胱癌的管腔亚型中富集，并且增加和减少NECTIN 4可以 增强EV敏感性或导致电阻。周博士假设转录因子 PPARG调节管腔膀胱癌细胞身份并整合脂肪酸信号传导，是一种直接的 NECTIN 4的调节因子，并且在尿路上皮癌细胞中瞬时增加NECTIN 4表达将 增强NECTIN 4靶向治疗的疗效。在目标1和2中，周博士将阐明其机制 作为这一调节途径的基础，并确定对NECTIN 4靶向治疗的敏感性是否可以被 通过使用药理学方法、生物修饰剂和 饮食改变在目标3中，Chou博士将确定PPARg的丢失或替代地， EMT相关的TGF β通路下调NECTIN 4，从而导致耐药性。他将利用EV- 耐药细胞系，他已经产生，患者来源的异种移植（PDX）模型（建立从少数 在UCSF治疗的患者），以及来自接受EV治疗的UCSF患者的转移性活检样本， 实现这个目标。周博士的培训和研究计划包括结构化的课程和 研讨会，一对一的教程，和动手研究的经验，这一切都将发生在加州大学旧金山分校，一个世界- 著名的NCCN癌症中心，在基础和转化癌症研究方面具有卓越的历史。博士 周的培训计划将补充他现有的专业知识，在以下领域建立坚实的基础： 膀胱癌生物学; 2）ADC和过继性T细胞疗法的临床前建模; 3）癌症代谢和 耐药性;和4）基因组学和下一代测序方法和分析。该项目将 在放射肿瘤学教授兼副主任Felix Feng博士的指导下进行 转化科学，并共同指导博士艾伦阿什沃思，医学教授和总统的 加州大学旧金山分校癌症中心他召集了一个杰出的咨询小组， 他的研究和职业道路。在这个奖项完成后，周博士将有相关的教学和 研究经验，成为膀胱癌模型，治疗靶向策略和基因组 研究耐药性的方法，包括对ADC的耐药性。如果成功，该项目还将提供 从实验室到临床的转化机会，利用饮食调整和噻唑烷二酮 药物组合，以增强反应，并可能逆转耐药性NECTIN 4靶向治疗。

PROJECT SUMMARY The goal of this K08 application is to provide Dr. Jonathan Chou, an Instructor of Medicine at UCSF, with the skills he will need to become an independently-funded laboratory investigator. Dr. Chou proposes to elucidate the regulatory mechanisms of NECTIN4, the target of a newly approved antibody-drug conjugate (ADC) in metastatic urothelial cancer called enfortumab vedotin (EV) and identify mechanisms of resistance using PDX and metastatic biopsy samples. The proposal builds on Dr. Chou’s recent work, which showed that NECTIN4 expression is enriched in luminal subtypes of bladder cancer, and that increasing and decreasing NECTIN4 can enhance EV sensitivity or lead to resistance, respectively. Dr. Chou hypothesizes that the transcription factor PPARG, which regulates luminal bladder cancer cell identity and integrates fatty acid signaling, is a direct regulator of NECTIN4 and that transiently augmenting NECTIN4 expression in urothelial cancer cells will enhance the efficacy of NECTIN4-targeting therapies. In Aims 1 and 2, Dr. Chou will elucidate the mechanism underlying this regulatory pathway and determine whether sensitivity to NECTIN4-targeted therapies can be enhanced by directly modulating the PPARg pathway using pharmacologic approaches, biological modifiers and dietary alterations. In Aim 3, Dr. Chou will determine whether loss of PPARg or alternatively, activation of the EMT-associated TGFb pathway downregulates NECTIN4, thus leading to resistance. He will leverage EV- resistant cell lines that he has generated, patient-derived xenograft (PDX) models (established from minority patients treated at UCSF), as well as metastatic biopsy samples from UCSF patients treated on EV, to accomplish this Aim. Dr. Chou’s training and research plan includes a combination of structured coursework and workshops, one-on-one tutorials, and hands-on research experience that will all take place at UCSF, a world- renowned NCCN Cancer Center with a history of excellence in basic and translational cancer research. Dr. Chou’s training plan will complement his existing expertise to build a strong foundation in the following areas: 1) bladder cancer biology; 2) preclinical modeling of ADCs and adoptive T cell therapies; 3) cancer metabolism and drug resistance; and 4) genomics and next-generation sequencing methods and analysis. The project will be conducted under the mentorship of Dr. Felix Feng, Professor of Radiation Oncology and Associate Director for Translational Sciences, and co-mentored by Dr. Alan Ashworth, Professor of Medicine and President of the UCSF Cancer Center. He has assembled a distinguished advisory panel with complementary expertise to guide his research and career path. At the completion of this award, Dr. Chou will have the relevant didactic and research experience to become a leader in bladder cancer models, therapeutic targeting strategies and genomic approaches to investigate drug resistance, including to ADCs. If successful, this project will also provide a translational opportunity from the laboratory to the clinic, to utilize dietary modifications and thiazolidinedione drug combinations to augment responses and potentially reverse resistance to NECTIN4-targeting therapies.