Identification of Genes Involved in Bladder Cancer

描述(申请人提供)：项目摘要：在发达国家，膀胱移行细胞癌(TCC)的发病率在所有癌症中排名第四，但其发生和发展的机制仍不清楚。这种疾病的诊断或预后生物标志物也很少。这项建议的长期目标是确定在TCC发展的早期和晚期所涉及的分子机制。此外，我们还希望为TCC的检测、诊断和预后寻找新的生物标志物。为了实现这一点，我们将使用膀胱癌小鼠模型，在该模型中，SV40大T抗原(SV40T)在尿路蛋白启动子的控制下表达，该启动子将表达限制在膀胱尿路上皮。这些小鼠(UPII-SV40T)发生移行细胞癌，之前的情况类似于人类独联体。提出的假设是侵袭性膀胱移行细胞癌和膀胱移行细胞癌以及膀胱移行细胞癌和远端正常尿路上皮在基因表达谱和基因调控网络上存在差异，这些变化预示着肿瘤的恶性状态。这一假说是基于多步骤致癌的概念。我们的假设的延伸是，CIS是正常尿路上皮和侵袭性TCC之间的中间步骤，并且应该有与这一中间状态相对应的基因表达的变化。具体目的是：1.利用Affymetrix基因芯片芯片(Affymetrix GeneChip(R))芯片，筛选非转基因小鼠和UPII-SV40T小鼠正常尿路上皮细胞、CIS和TCC之间差异表达的基因和基因调控网络。单个基因与人类膀胱移行细胞癌的相关性将通过评估人类同源基因在患者膀胱移行细胞癌和正常尿路上皮标本中的表达来验证。在微阵列数据的电子分析中，将执行包括生成基因表达谱(聚类分析)和基于差异表达基因的启动子序列的启动子模型的开发。2.通过在人膀胱源细胞系中稳定过表达或siRNA介导的抑制，评估这些基因在体内的功能和与膀胱癌发生的潜在相关性。相关：这些研究的完成将促进我们对膀胱移行细胞癌发生的分子事件的理解。此外，鉴定正常尿路上皮、膀胱移行细胞癌和膀胱移行细胞癌之间的差异表达基因将为该病提供急需的诊断和预后标记物。

DESCRIPTION (provided by applicant): Project Summary: Transitional cell carcinoma of the bladder (TCC) ranks 4th in incidence of all cancers in the developed world, yet the mechanisms of its origin and progression remain poorly understood. There are also few useful diagnostic or prognostic biomarkers for this disease. The long-term aim of this proposal is to determine molecular mechanisms involved in early and late steps in the development of TCC. In addition we hope to identify new biomarkers for detection, diagnosis and prognosis of TCC. To accomplish this we will use a mouse model for bladder cancer in which the SV40 large T antigen (SV40 T) is expressed under the control of the uroplakin promoter, which restricts expression to the bladder urothelium. These mice (UPII- SV40T) develop TCC, which is preceded by a condition resembling human CIS. The hypothesis underlying this proposal is that there are differences in gene expression profiles and gene regulatory networks between invasive TCC and CIS and between CIS and distant normal appearing urothelium, and that these changes are indicative of the malignant state. This hypothesis is based on the multistep carcinogenesis concept. An extension of our hypothesis is that CIS is an intermediate step between normal urothelium and invasive TCC and that there should be changes in gene expression corresponding to this intermediate state. The specific aims are: 1. Identify the genes and gene regulatory networks that are differentially expressed between the normal urothelium of nontransgenic and UPII-SV40T mice, CIS and TCC, using Affymetrix GeneChip(r) Arrays. The relevence of individual genes to human TCC will be validated by assessing expression of the human homologs in patient TCC and normal urothelium specimens. In silico analysis of the microarray data, which includes generating gene expression profiles (clustering analysis) and the development of promoter models based on the promoter sequences of the differentially expressed genes will be performed. 2. Assess the function and potential relevance to bladder carcinogenesis of these genes in vivo by stable overexpression, or siRNA-mediated suppression, of the validated genes in human bladder-derived cell lines. Relevence: Completion of these studies should advance our understanding of the molecular events underlying TCC development. In addition, the identification of genes differentially expressed between normal urothelium, CIS and TCC will provide much needed diagnostic and prognostic markers for this disease.