Alternative splicing and epithelial-mesenchymal plasticity in prostate tumors

前列腺肿瘤中的选择性剪接和上皮间质可塑性

• 批准号: 7991827
• 负责人: Mariano A. Garcia-Blanco
• 金额: $ 31.4万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-12-01 至 2013-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7991827
• 关键词: Alternative Splicing; American Cancer Society; Behavior; Cells; Data; Disease; Distant; Epithelial; Epithelial Cells; Exons; Fibroblast Growth Factor Receptor 2; Gene Expression; Goals; Health; Human; Image; Malignant neoplasm of prostate; Mammals; Mesenchymal; Metastatic to; Molecular Profiling; Neoplasm Metastasis; New York; Outcome; Patients; Primary Neoplasm; Process; Property; Prostate; Prostate carcinoma; Prostatic Neoplasms; Protein Isoforms; RNA Splicing; Rattus; Regulation; Reporter; Reporting; Signal Transduction; System; Technology; Testing; Therapeutic; Time; Transcript; Tumor Markers; Vertebrates; Work; fitness; in vivo; killings; men; mouse model; neoplastic cell; novel; programs; therapeutic target; tumor; tumor progression; tumorigenesis

DESCRIPTION (provided by applicant): In epithelial cells alternative splicing of fibroblast growth factor receptor-2 (FGFR2) transcripts leads to the expression of the FGFR2(IIIb) isoform, whereas in mesenchymal cells the same process results in the synthesis of FGFR2(IIIc), which include exon IIIc. This regulated splicing is disrupted during progression of prostate carcinomas leading to the inappropriate expression of FGFR2 isoforms. To visualize the use of FGFR2 exon IIIc in Dunning AT3 tumors in syngeneic rats we constructed minigene constructs that report on alternative splicing. Imaging these alternative splicing decisions revealed unexpected mesenchymal-epithelial transitions (MET) in these primary tumors. The understanding of this epithelial-mesenchymal plasticity, revealed by differences in splicing, is the overarching goal of this application. To this end we propose to accomplish the following specific aims: Specific Aim 1. To characterize the connections between FGFR2 splicing and epithelial-mesenchymal plasticity in prostate tumors. We have developed a new bichromatic reporter that can be used to detect both MET and epithelial-mesenchymal transitions (EMT). We have also extended our observations to well characterized human prostate tumor cells in culture. Work accomplished in this aim will test the hypothesis that epithelial plasticity is a general property of aggressive prostate carcinomas in humans. Specific Aim 2. To characterize the epithelial-mesenchymal plasticity in primary prostate tumors revealed by alterations in splicing. In this aim we will characterize the molecular signatures and behavior of the MET clusters in primary tumors. Specific aim 3. To characterize the connections between epithelial-mesenchymal plasticity and metastatic behavior. We will investigate the connections between epithelial-mesenchymal plasticity and metastatic behavior. Finally, we will isolate circulating prostate tumor cells from both the AT3 rat tumors and patients, and we will determine their FGFR2 splicing status and their epithelial state. Work accomplished in aim two and in this aim will test the hypothesis that epithelial-mesenchymal plasticity leads to increased tumor fitness. The significance of this work is twofold: First we will unravel basic information about gene expression programs controlled by alternative splicing during prostate tumor progression. Second, the potential significance to human health is underscored by the magnitude of prostate cancer as a health problem. Identifying the tumors/cells that will progress to metastatic disease is a challenge and a priority. The work proposed here should identify useful markers and perhaps even therapeutic targets. PUBLIC HEALTH RELEVANCE: The potential significance of our application to human health is underscored by the magnitude of prostate cancer as a health problem, which The American Cancer Society (ACS) predicts will afflict ~200,000 men and will kill >25,000 in the US alone. In addition, prostate cancer presents the clinician and the patient with unique problems in terms of choosing among therapeutic options and predicting eventual outcomes (see New York Times 26 February article "A Review of Prostate Cancer Leaves Men in a Muddle"). The work proposed here should identify useful markers of tumor behavior and perhaps even targets for novel therapies.

描述（由申请人提供）：在上皮细胞中，成纤维细胞生长因子受体 2 (FGFR2) 转录物的选择性剪接导致 FGFR2(IIIb) 同工型的表达，而在间充质细胞中，相同的过程导致 FGFR2(IIIc) 的合成，其中包括外显子 IIIc。 这种受调节的剪接在前列腺癌的进展过程中被破坏，导致 FGFR2 亚型的不适当表达。 为了可视化 FGFR2 外显子 IIIc 在同基因大鼠 Dunning AT3 肿瘤中的使用，我们构建了报告选择性剪接的小基因构建体。 对这些选择性剪接决策进行成像揭示了这些原发性肿瘤中意想不到的间充质-上皮转变（MET）。 通过剪接差异揭示的这种上皮间质可塑性的理解是本应用的首要目标。 为此，我们建议实现以下具体目标： 具体目标 1. 表征前列腺肿瘤中 FGFR2 剪接与上皮间质可塑性之间的联系。 我们开发了一种新的双色报告基因，可用于检测 MET 和上皮间质转化 (EMT)。 我们还将我们的观察扩展到培养中已明确表征的人类前列腺肿瘤细胞。 在这一目标中完成的工作将检验上皮可塑性是人类侵袭性前列腺癌的一般特性的假设。 具体目标 2. 表征通过剪接改变揭示的原发性前列腺肿瘤中的上皮-间质可塑性。 为此，我们将表征原发性肿瘤中 MET 簇的分子特征和行为。 具体目标 3. 表征上皮间质可塑性与转移行为之间的联系。 我们将研究上皮间质可塑性与转移行为之间的联系。 最后，我们将从 AT3 大鼠肿瘤和患者中分离循环前列腺肿瘤细胞，并确定它们的 FGFR2 剪接状态和上皮状态。 目标二和本目标中完成的工作将检验上皮间质可塑性导致肿瘤适应性增加的假设。 这项工作的意义是双重的：首先，我们将揭示前列腺肿瘤进展过程中由选择性剪接控制的基因表达程序的基本信息。 其次，前列腺癌作为一个健康问题的严重性凸显了其对人类健康的潜在重要性。 识别将进展为转移性疾病的肿瘤/细胞是一项挑战，也是当务之急。 这里提出的工作应该确定有用的标记物，甚至可能是治疗靶点。 公共健康相关性：前列腺癌作为一个健康问题的严重程度凸显了我们的应用对人类健康的潜在意义，美国癌症协会 (ACS) 预测，仅在美国，前列腺癌将困扰约 200,000 名男性，并导致超过 25,000 人死亡。 此外，前列腺癌在选择治疗方案和预测最终结果方面给临床医生和患者带来了独特的问题（参见《纽约时报》2 月 26 日文章“前列腺癌综述让男性陷入混乱”）。 这里提出的工作应该确定肿瘤行为的有用标记，甚至可能是新疗法的目标。