Therapeutic implication of RB1 loss in bladder cancer

摘要 本提案描述了一项为期5年的研究职业发展计划，重点是RB1的非规范角色 在膀胱癌中的损失。李强博士是罗斯威尔公园综合体的肿瘤学助理教授 泌尿外科癌症中心。这项提议建立在候选人以前的经验和 目前的研究项目使用了基因工程小鼠模型(GEMM)和有机化合物。建议数 实验和培训将使他能够过渡到独立成为膀胱癌内科科学家 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RB1方面的专家 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。这个 培训计划包括以下目标：(1)加强临床前癌症建模方面的专门知识(GEMM和 有机物)；(2)探讨膀胱癌细胞可塑性和耐药的分子机制； (3)获得生物信息学分析方面的专业知识。 Rb1突变可预测膀胱癌新辅助化疗后的病理反应。其他 临床观察提示，基底层类型的膀胱癌对化疗的反应更大。 而不是流线型。然而，RB1缺失对膀胱癌分子亚型的生物学影响 其发病机制和化疗反应尚不清楚。新发现的RB1的特征 其他癌症类型中的通路表明RB1缺失促进了谱系可塑性和获得性治疗 抵抗。因此，我们假设RB1缺失促进了膀胱癌的进展、转移和细胞分化。 可塑性(管腔到基底部，以及治疗阻力)。我们使用了两种转基因小鼠系统(Uroplakin II 驱动反向四环素反式激活剂(Tre-Cre)在膀胱尿路上皮细胞RB1缺失中的作用 在多西环素控制下促进肿瘤抑制基因(TrP53、Pten、Rb1)的缺失。 我们设计了多西环素可诱导的三重基因敲除小鼠Trp53-/-：PTEN-/-：Rb1-/-(简称TKO)和Double 基因敲除小鼠TrP53-/-：PTEN-/-(简称DKO)。我们提出了以下具体目标：(1)明确职能 RB1缺失在加速膀胱癌GEMM的肿瘤进展、转移和细胞可塑性中的作用；(2) 来源细胞对将军澳膀胱癌发生、转移及化疗反应的影响 肿瘤起源于基底细胞而不是腔细胞。这项提案的成功完成将使 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的候选人 并进一步发展成为一名独立的内科科学家。这项工作还将建立试验性的 将为候选人的独立研究计划提供基础的模型和分析管道。

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.