Therapeutic implication of RB1 loss in bladder cancer

摘要 该提案描述了一个为期5年的研究职业发展计划，重点是RB 1的非规范作用 膀胱癌的损失。李强博士是罗斯韦尔公园综合医院的肿瘤学助理教授 泌尿外科癌症中心。建议书以候选人以往的经验为基础， 目前的研究项目使用基因工程小鼠模型（GEMM）和类器官。拟议 实验和培训将使他能够过渡到独立作为一个医生科学家在膀胱癌 翻译研究他将主要由大卫古德里奇博士指导。古德里奇博士是RB 1的专家 癌症生物学、基因工程小鼠模型、获得性耐药性和癌细胞可塑性。的 培训计划包括以下目标：（1）提高临床前癌症建模（GEMM和 （2）探索膀胱癌细胞可塑性和耐药性的分子机制;以及 (3)获得生物信息学分析的专业知识。 RB 1突变可预测膀胱癌新辅助化疗后的病理反应其他 临床观察表明，基底型膀胱癌更可能对化疗有反应， 而不是管腔型。然而，RB 1缺失对膀胱癌分子亚型的生物学影响 发病机制和化疗反应尚未研究。新发现的RB 1特征 其他癌症类型的RB 1通路表明，RB 1缺失促进谱系可塑性和获得性治疗。 阻力因此，我们假设RB 1缺失促进膀胱癌进展、转移和细胞凋亡。 可塑性（管腔至基底，和治疗抗性）。我们使用两种转基因小鼠系统（Uroplakin II 驱动的反向四环素反式激活因子，TRE-Cre），以研究RB 1丢失在膀胱尿路刺激中的作用， 在多西环素施用的控制下促进肿瘤抑制基因（Trp 53、Pten、Rb 1）的缺失。 我们设计了多西环素诱导的Trp 53-/-：Pten-/-：Rb 1-/-三重敲除小鼠（称为TKO）和双敲除小鼠（称为双敲除小鼠）。 敲除小鼠Trp 53-/-：Pten-/-（称为DKO）。我们提出以下具体目标：（1）定义功能 RB 1缺失在膀胱癌GEMM中加速肿瘤进展、转移和细胞可塑性;（2） 分析TKO中来源细胞对膀胱肿瘤发生、转移和化疗反应的影响 肿瘤来源于基底细胞与腔细胞。成功完成此提案将使 候选人在晚期膀胱癌的临床前建模方面获得有价值的技术知识和专业知识 并进一步发展成为一名独立的医学科学家。这项工作还将建立实验性的 模型和分析管道，这将为候选人的独立研究计划提供基础。

Abstract This proposal describes a 5-year research career development program focused on a non-canonical role of RB1 loss in bladder cancer. Dr. Qiang Li is an Assistant Professor of Oncology at Roswell Park Comprehensive Cancer Center in the Department of Urology. The proposal builds on the candidate’s previous experience and current research projects using genetically engineered mouse models (GEMMs) and organoids. The proposed experiments and training will enable his transition to independence as a physician scientist in bladder cancer translational research. He will be mentored primarily by Dr. David Goodrich. Dr. Goodrich is an expert in RB1 cancer biology, genetically engineered mouse models, acquired drug resistance and cancer cell plasticity. The training plan includes the following goals: (1) Enhance expertise in preclinical cancer modeling (GEMM and organoids); (2) Probe the molecular mechanisms of bladder cancer cellular plasticity and drug resistance; and (3) Gain expertise in bioinformatic analysis. RB1 mutations are predictive of pathologic response after neoadjuvant chemotherapy in bladder cancer. Other clinical observations suggest that the basal type of bladder cancer is more likely to respond to chemotherapy than the luminal type. However, the biological impact of RB1 loss on molecular subtypes of bladder cancer pathogenesis and chemotherapy response has not been investigated. Newly discovered features of the RB1 pathway in other cancer types suggest that RB1 loss promotes lineage plasticity and acquired therapy resistance. Thus, we hypothesize that RB1 loss promotes bladder cancer progression, metastasis, and cellular plasticity (luminal to basal, and therapeutic resistance). We use two transgenic mouse systems (Uroplakin II driven reverse tetracycline trans-activator, TRE-Cre) to investigate the role of RB1 loss in bladder urothelium by facilitating deletion of tumor suppressor genes (Trp53, Pten, Rb1) under control of doxycycline administration. We engineered doxycycline inducible triple knockout mice Trp53-/-: Pten-/-: Rb1-/- (referred as TKO) and double knockout mice Trp53-/-: Pten-/- (referred as DKO). We propose the following Specific Aims: (1) Define the function of RB1 loss in accelerating tumor progression, metastasis, and cellular plasticity in bladder cancer GEMMs; (2) Dissect the impact of cell-of-origin on bladder tumorigenesis, metastasis and response to chemotherapy in TKO tumors derived from basal cells versus luminal cells. Successful completion of this proposal will allow the candidate to gain valuable technical knowledge and expertise in preclinical modeling of advanced bladder cancer and further his development as an independent physician scientist. The work will also establish experimental models and analysis pipelines that will provide the foundation for the candidate’s independent research program.