RAl GTPases and partners in human bladder cancer metastasis

RAl GTP酶及其在人膀胱癌转移中的伙伴

• 批准号: 7807115
• 负责人: DAN THEODORESCU
• 金额: $ 35.13万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-01 至 2013-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7807115
• 关键词: Abbreviations; Affect; American; Antibodies; Automobile Driving; Behavior; Binding; Binding Proteins; Binding Sites; Bioinformatics; Biological Markers; Bladder Neoplasm; Cancer Prognosis; Cancer cell line; Carcinogen exposure; Cause of Death; Chemical Exposure; Chemicals; Chimera organism; Confocal Microscopy; Consensus; Data; Development; Disease; Dyes; EGFR Protein Overexpression; Elements; Epidermal Growth Factor Receptor; Family; Figs - dietary; Foundations; Friends; Future; Gene Expression; Gene Expression Profile; Gene Expression Profiling; Genes; Genetic Transcription; Glycoproteins; Goals; Growth; Guanosine Triphosphate Phosphohydrolases; Human; Human Development; Image; Immigration; Immunotherapy; In Vitro; Kinetics; Knock-out; Knockout Mice; Knowledge; Link; Lung; Malignant Neoplasms; Malignant neoplasm of urinary bladder; Mediating; Membrane Proteins; Metastatic to; Modeling; Molecular; Molecular Profiling; Monoclonal Antibodies; Monomeric GTP-Binding Proteins; Mus; Mutation; Neoplasm Metastasis; Nuclear; PTEN gene; Pancreas; Pathway interactions; Patients; Phenotype; Phosphatidylinositols; Phosphoric Monoester Hydrolases; Phosphorylation; Play; Process; Prognostic Factor; Protein Overexpression; Proteins; Proto-Oncogene Proteins c-akt; Recurrence; Regulation; Research Project Grants; Risk; Role; Signal Pathway; Signal Transduction; Site; Site-Directed Mutagenesis; Small Interfering RNA; Smoking; Stratification; Tertiary Protein Structure; Testing; Text; Therapeutic; Tissues; Wild Type Mouse; Xenograft procedure; Zinc Fingers; abstracting; base; cancer cell; cancer stem cell; cell motility; chemical carcinogen; chemical carcinogenesis; computerized tools; drug discovery; epidemiologic data; expectation; genome wide association study; genome-wide; genome-wide analysis; in vivo; insight; killings; loss of function; lung xenograft; malignant breast neoplasm; member; migration; mutant; novel; novel therapeutic intervention; novel therapeutics; outcome forecast; overexpression; paralogous gene; preclinical study; prognostic; promoter; real time model; repository; research study; therapeutic target; tool; transcription factor; translational study; tumor; tumor growth; tumor progression

DESCRIPTION (provided by applicant): Bladder cancer kills 13,000 Americans each year, but very few research projects target this disease. Most of these deaths are due to metastatic spread, commonly to the lungs. A fuller understanding of the molecular mechanisms driving growth and dissemination of bladder cancer is likely to provide new therapeutic opportunities. RalA and RalB, two homologous GTPases play an important role in growth and lung metastasis in xenograft models of human bladder cancer. Furthermore, these paralogs are activated by phosphorylation at sites regulated by Aurora-A and PKC, two kinases associated with human bladder cancer growth and progression. To define signaling pathways downstream of Ral, genome-wide analysis of Ral dependent gene expression was carried out and revealed that RalA and RalB regulate the expression of CD24, a GPI-linked glycoprotein and biomarker of metastasis development in bladder cancer. Moreover, this data identified the zinc finger transcription factor RREB1 as a putative regulator of CD24 expression and RalBP1, an effector of both Ral paralogs, as a regulator of RREB1 activity. Based on this data, we formulate the Guiding Hypothesis that RalA and RalB regulate a new downstream signaling pathway consisting of RalBP1, RREB1 and CD24 via which they contribute to bladder cancer growth and lung metastasis and furthermore, that biomarkers of RalA and RalB activation such as phosphorylation or transcriptional signatures are prognostic for development of bladder cancer metastasis in patients. Three Specific Aims test this hypothesis: In Aim 1, the role of RalA and RalB phosphorylation in bladder cancer growth, migration and lung metastasis will be determined using phospho inactive mutants. The prognostic relevance of Ral paralog phosphorylation to metastasis development will be evaluated in tissues from patients with locally advanced bladder cancer. Aim 2 will determine how RalBP1 regulates RREB1 activity and how RREB1 in turn, regulates CD24 expression. Since genome-wide profiling of Ral dependent gene expression led to the discovery of CD24, we will use tissues from Aim 1 and advanced computational tools to generate paralog specific signatures of Ral expression. The ability of these signatures to predict the development of metastatic disease in patients will be evaluated. In Aim 3 we evaluate the requirement of CD24 for bladder carcinogenesis and progression. A CD24 knockout mouse will be used to study the necessity of CD24 in chemically induced bladder carcinogenesis and/or subsequent invasion and metastasis of resultant tumors. A separate study will test whether anti-CD24 antibodies can inhibit growth of established bladder cancer lung metastases. Establishing the biological relevance of Ral phosphorylation to bladder cancer lung metastasis and the regulatory connections between RalBP1, RREB1 and CD24 provide opportunities for therapy. Translational studies associated with this mechanistic work provide biomarker predictors for metastasis development in patients while a preclinical study provides a foundation for the near term development of novel therapies directed at established metastatic disease. PUBLIC HEALTH RELEVANCE: Bladder cancer kills 13,000 Americans each year, but few research projects are targeted to this disease. For most of these patients, the cause of death is attributable to metastatic spread, commonly to the lungs. The goal of this project is to understand the mechanisms that underlie lung metastasis in human bladder cancer and use this knowledge to predict and treat this condition in patients.

描述(由申请者提供)：膀胱癌每年导致13,000名美国人死亡，但针对这种疾病的研究项目很少。这些死亡中的大多数是由于转移的扩散，通常是肺部。更全面地了解推动膀胱癌生长和扩散的分子机制可能会提供新的治疗机会。Rala和RalB是两个同源的GTP酶，在人膀胱癌异种移植模型的生长和肺转移中起重要作用。此外，这些Paralog被Aurora-A和PKC调节的位点的磷酸化激活，这两个激酶与人类膀胱癌的生长和进展有关。为了确定Ral下游的信号通路，对Ral依赖的基因表达进行了全基因组分析，发现Rala和RalB调节CD24的表达，CD24是一种GPI连接的糖蛋白，也是膀胱癌转移发展的生物标志物。此外，这些数据表明，锌指转录因子RREB1是CD24表达的假定调节因子，而RalBP1是RREB1活性的调节因子。基于这一数据，我们提出了一个指导性假设，即Rala和RalB调控由RalBP1、RREB1和CD24组成的新的下游信号通路，它们通过这一途径促进膀胱癌的生长和肺转移，此外，Rala和RalB激活的生物标记物，如磷酸化或转录标志，可预测患者膀胱癌转移的发生。三个特定的目标验证了这一假设：在目标1中，Rala和RalB的磷酸化在膀胱癌生长、转移和肺转移中的作用将通过磷酸化失活突变体来确定。在局部晚期膀胱癌患者的组织中，Ral-paralog磷酸化与转移发展的预后相关性将被评估。目的2将确定RalBP1如何调节RREB1的活性，以及RREB1如何反过来调节CD24的表达。由于对ral依赖基因表达的全基因组分析导致了CD24的发现，我们将使用Aim 1的组织和先进的计算工具来生成ral表达的Paralog特异性签名。将评估这些信号预测患者转移性疾病发展的能力。在目的3中，我们评估CD24在膀胱癌发生和发展中的需求。CD24基因敲除小鼠将被用来研究CD24在化学诱导的膀胱癌发生和/或随后的肿瘤侵袭和转移中的必要性。另一项单独的研究将测试抗CD24抗体是否可以抑制已确定的膀胱癌肺转移的生长。Ral磷酸化与膀胱癌肺转移的生物学相关性以及RalBP1、RREB1和CD24之间的调控联系为治疗提供了机会。与这一机制相关的翻译研究为患者的转移发展提供了生物标志物预测指标，而临床前研究则为近期针对已建立的转移疾病的新疗法的开发提供了基础。公共卫生相关性：膀胱癌每年导致1.3万美国人死亡，但很少有研究项目针对这种疾病。对于这些患者中的大多数，死亡原因可归因于转移性扩散，通常是肺转移。该项目的目标是了解人类膀胱癌肺转移的潜在机制，并利用这一知识来预测和治疗患者的这种情况。