Molecular Diversity in Bladder Cancer

描述(申请人提供)：我们开发了一种体内选择系统，其中选择性地归属于不同组织的多肽在静脉注射噬菌体随机多肽库后被回收。在早期的工作中，我们发现了一个以前未被识别的地址系统，它使肿瘤的器官特异性靶向和血管生成相关靶向成为可能。靶向肿瘤的多肽的相应受体是在肿瘤进展过程中上调或激活的细胞表面标志物。我们还开发了评估这种探针在体内的器官特异性和细胞类型分布的方法。我们的工作假设是，膀胱中存在与组织相关和与肿瘤分期相关的异质性；这种多样性可能会影响对治疗的反应。在这里，我们建议定义存在于(I)正常尿路上皮和(Ii)膀胱癌的细胞和分子差异。在具体目标#1下，我们将探索基于体内和体外噬菌体展示与激光捕获显微切割(LCM)技术相结合的新策略。我们的目标是分离在体内定位于小鼠膀胱的多肽，或在体外与各种类型的膀胱细胞结合的多肽。在特定的目标#2下，我们将分离出肿瘤从早期转移到晚期转移的不同阶段膀胱中的多肽和抗体。在一种补充策略中，我们将选择在膀胱癌进展的特定阶段被循环免疫球蛋白池识别的多肽。这些特定的探针将用于识别新的肿瘤和肿瘤相关抗原。在特定的目标#3下，我们将分离、克隆和评估这些特异性和肿瘤特异性标记物在膀胱癌进展中的表达模式和功能。新的膀胱和膀胱癌受体的鉴定可能有助于揭示膀胱复杂的细胞和分子多样性。在特定目标#4下，我们将确定具有内化尿路上皮细胞能力的特定多肽。紧密的细胞连接、含有糖胺多聚糖(GAG)的特殊管腔细胞表面和粘蛋白层相结合，可以保护哺乳动物的尿路上皮免受浓缩尿液化学物质和微生物黏附的影响。然而，在病理条件下，尿路上皮的这些特征会成为将治疗药物有效地输送到膀胱的障碍。在这里，我们建议寻找能够内化到尿路上皮细胞的候选多肽，以开发治疗膀胱癌的靶向策略。

DESCRIPTION (provided by applicant): We have developed an in vivo selection system in which peptides that home selectively to different tissues are recovered after intravenous administration of a phage random peptide library. In earlier work, we uncovered a previously unrecognized address system that makes possible organ-specific targeting and angiogenesis-related targeting of tumors. The corresponding receptors for the peptides targeting tumors are cell surface markers that are upregulated or activated during tumor progression. We also developed methods for assessing organ-specificity and cell-type distribution of such probes in vivo. Our working hypothesis is that there are tissue-related and tumor stage related heterogeneity in the bladder; such diversity may affect the responses to therapies. Here, we propose to define the cellular and molecular differences that exist (i) in normal urothelium and (ii) in bladder cancer. Under Specific Aim #1, we will explore novel strategies based on in vivo and ex-vivo phage display combined with Laser Capture Microdissection (LCM) technologies. We aim to isolate peptides that home in vivo to the mouse bladder or that bind ex vivo to various bladder cell types. Under Specific Aim #2, we will isolate peptides and antibodies that home to the bladder at different stages of tumor progression, from early to late metastatic disease. In a complementary strategy, we will select peptides that are recognized by the circulating pool of immunoglobulins at selected stages of bladder cancer progression. These specific probes will be used to identify new tumor- and tumor-associated antigens. Under Specific Aim #3, we will isolate, clone, and evaluate the expression pattern and function of these specific and tumor-specific markers in the context of bladder cancer progression. The identification of novel bladder and bladder cancer receptors may shed light in the complex cellular and molecular diversity of the bladder. Under Specific Aim #4, we will identify specific peptides that have the ability to internalize into urothelial cells. The combination of tight cell junctions, a specialized luminal cell surface bearing glycosaminoglycans (GAG), and a mucin layer protect the mammalian urothelium against concentrated urine chemicals and microbial adhesion. However, under pathological conditions, such features of the urothelium become obstacles to effective delivery of therapeutic agents to the bladder. Herein we propose to pursue candidate peptides with the ability to internalize into urothelial cells to develop therapeutic targeting strategies for the treatment of bladder cancer.