Caffeine regulates splicing of cancer-related genes: dissecting the mechanism

咖啡因调节癌症相关基因的剪接：剖析其机制

• 批准号: 8034755
• 负责人: KATHLEEN W. SCOTTO
• 金额: $ 8.81万
• 依托单位: UNIV OF MED/DENT NJ-R W JOHNSON MED SCH
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-05-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8034755
• 关键词: Alternative Splicing; Animal Model; Biological Markers; Caffeine; Cells; Consumption; Data; Defect; Development; Diagnostic; Diet; Disease; Elements; FGFR2 gene; Fibronectins; Gene Expression Regulation; Genes; Human; In Vitro; Knowledge; Maintenance; Malignant Neoplasms; Mediating; Modeling; Molecular; Normal Cell; Normal tissue morphology; Oncogenes; Onset of illness; Pathway interactions; Phenotype; Phosphotransferases; Physiological; Play; Protein Isoforms; Proteins; Proteomics; Purinergic P1 Receptors; RNA Splicing; Regulation; Role; Ryanodine Receptors; Signal Pathway; Signal Transduction; Site; Spliceosomes; Transcript; Tumor Suppressor Proteins; Variant; cancer cell; carcinogenesis; human CHEK1 protein; human disease; in vivo; infancy; interest; mRNA Precursor; malignant state; novel; overexpression; phosphoric diester hydrolase; prototype; response; therapeutic target; tumor

DESCRIPTION (provided by applicant): Alternative splicing of pre-mRNA contributes significantly to human proteomic complexity and functional diversity, playing a key role in developmental decisions, gene expression regulation and, when aberrant, in human disease onset. Importantly, over 1000 splicing variants have been associated with the cancer phenotype. Although the functional analysis of these variants and their possible role in cancer is still in its infancy, their potential importance as cancer biomarkers/therapeutic targets has garnered much interest. We now present a substantial body of preliminary data showing that caffeine, a highly consumed stimulant in the human diet, induces alternative splicing of a large subset of cancer-related genes including the tumor suppressor KLF6. Using KLF6 as a prototype, we have shown that this induction is rapid and reversible and occurs at the level of splicing rather than differential stability. We also demonstrate that the four classic caffeine signaling pathways have little if any role in caffeine-induced alternative splicing, indicating that a novel molecular mechanism is operative. Importantly, since the previous submission we have found that alternative splicing of KLF6 is regulated by the SR protein SC35, and that this protein is induced by caffeine. We now hypothesize that caffeine regulates alternative splicing, at least in part, by the induction of SC35, and may mimic an endogenous pathway aberrantly activated in cancer cells. To further dissect the impact of caffeine on the splicing of cancer-related genes, we now propose to: 1) Investigate the role of SC35 in caffeine-mediated alternative splicing, using KLF6 as a prototype; 2) Investigate the interaction of splicing factors with KLF6 ESS-1 and ISE-1 in vitro and in vivo, and interrogate a model for regulation of KLF6 splicing by SC35: 3) Determine the mechanism by which caffeine elevates SC35 and 4) Determine whether caffeine induces "cancer-specific" splice variants in normal tissues in vivo. Our observation that caffeine can regulate alternative splicing of a variety of genes involved in the cancer phenotype is both highly significant and timely. We expect that these studies will result in the identification of elements/factors/pathways that are common to the splicing regulation of this cancer gene subset. We also expect to determine whether high caffeine consumption can induce cancer-related splice variants in normal cells in vivo, resulting in transient expression that may confound both biomarker analysis and targeted therapy.

描述（由申请人提供）：前体 mRNA 的选择性剪接对人类蛋白质组复杂性和功能多样性有显着贡献，在发育决策、基因表达调控以及异常时在人类疾病发作中发挥关键作用。重要的是，超过 1000 种剪接变异与癌症表型相关。尽管这些变异的功能分析及其在癌症中可能的作用仍处于起步阶段，但它们作为癌症生物标志物/治疗靶点的潜在重要性引起了人们的极大兴趣。我们现在提供了大量的初步数据，表明咖啡因（人类饮食中一种高度消耗的兴奋剂）会诱导包括肿瘤抑制因子 KLF6 在内的大量癌症相关基因的选择性剪接。使用 KLF6 作为原型，我们表明这种诱导是快速且可逆的，并且发生在剪接水平而不是差异稳定性水平。我们还证明，四种经典的咖啡因信号通路在咖啡因诱导的选择性剪接中几乎没有任何作用，这表明一种新的分子机制正在发挥作用。重要的是，自上次提交以来，我们发现 KLF6 的选择性剪接受到 SR 蛋白 SC35 的调节，并且该蛋白是由咖啡因诱导的。我们现在假设咖啡因至少部分通过诱导 SC35 来调节选择性剪接，并且可能模拟癌细胞中异常激活的内源途径。为了进一步剖析咖啡因对癌症相关基因剪接的影响，我们现在建议：1）以KLF6为原型，研究SC35在咖啡因介导的选择性剪接中的作用； 2) 在体外和体内研究剪接因子与 KLF6 ESS-1 和 ISE-1 的相互作用，并询问 SC35 调节 KLF6 剪接的模型：3) 确定咖啡因升高 SC35 的机制，4) 确定咖啡因是否在体内诱导正常组织中的“癌症特异性”剪接变异体。我们观察到咖啡因可以调节与癌症表型相关的多种基因的选择性剪接，这一观察结果非常重要且及时。我们期望这些研究将鉴定出该癌症基因子集的剪接调节所共有的元件/因素/途径。我们还希望确定高咖啡因摄入是否会在体内诱导正常细胞中与癌症相关的剪接变异，从而导致短暂表达，这可能会混淆生物标志物分析和靶向治疗。