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

项目总结 这个K08应用程序的目标是为加州大学旧金山分校的医学讲师乔纳森·周博士提供 要成为一名独立资助的实验室调查员，他需要掌握一些技能。周博士建议澄清 新近批准的抗体-药物结合物(ADC)靶标NECTIN4的调控机制 转移性尿路上皮癌称为Enfortomab vedotin(EV)，并用PDX鉴定耐药机制 和转移的活组织检查样本。这项提议建立在周博士最近的研究基础上，该研究表明，NECTIN4 在膀胱癌的管腔亚型中表达丰富，并且NECTIN4的增加和减少可以 分别提高电动汽车的灵敏度或导致阻力。周博士假设转录因子 PPARG调节腔内膀胱癌细胞的特性并整合脂肪酸信号，是一种直接的 NECTIN4调节因子和瞬时增强尿路上皮癌细胞中NECTIN4的表达将 提高NECTIN4靶向治疗的疗效。在目标1和目标2中，周博士将阐明这种机制 并确定对NECTIN4靶向治疗的敏感性是否可以 通过使用药理学方法直接调节PPARg途径，生物修饰剂和 饮食上的改变。在Aim 3中，周博士将确定PPARg是否丢失，或者是否激活 EMT相关的TGFb通路下调NECTIN4，从而导致耐药。他将利用电动汽车- 他建立的耐药细胞系，患者来源的异种移植(PDX)模型(由少数人建立 在加州大学旧金山分校接受治疗的患者)，以及来自接受EV治疗的UCSF患者的转移活检样本，以 实现这一目标。周博士的培训和研究计划包括结构化的课程和 研讨会、一对一教程和实践研究体验都将在加州大学旧金山分校举行，这是一个 著名的NCCN癌症中心在基础和转化性癌症研究方面拥有卓越的历史。Dr。 周的培训计划将补充他现有的专业知识，在以下方面奠定坚实的基础：1) 膀胱癌生物学；2)ADC的临床前模型和过继T细胞疗法；3)癌症代谢和 耐药性；以及4)基因组学和下一代测序方法和分析。该项目将是 由放射肿瘤学教授兼副主任冯飞博士指导进行 翻译科学，由医学教授兼美国翻译学会会长艾伦·阿什沃思博士共同指导 加州大学旧金山分校癌症中心。他组建了一个具有互补专业知识的杰出顾问小组，以指导 他的研究和职业道路。在完成这一奖项后，周博士将拥有相关的教学和 在膀胱癌模型、治疗靶向策略和基因组学方面成为领先者的研究经验 调查耐药性的方法，包括对ADCs的耐药性。如果成功，这个项目还将提供一个 从实验室到临床的翻译机会，利用饮食改良剂和噻唑烷二酮 药物组合以增强反应并可能逆转对NECTIN4靶向治疗的耐药性。

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.