Post-translational Regulation of Inducible cAMP Early Repressor and its Implications in Cancer

诱导型 cAMP 早期阻遏蛋白的翻译后调节及其在癌症中的意义

• 批准号: 9922968
• 负责人: CARLOS A MOLINA
• 金额: $ 32.12万
• 依托单位: MONTCLAIR STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-01 至 2022-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9922968
• 关键词: Affect; Animal Cancer Model; BRAF gene; Binding; Biochemistry; Biological Assay; Biomedical Research; CDC2 gene; Cell Line; Cell Proliferation; Characteristics; Chromatin; Complex; Cyclic AMP; Cytoplasm; DNA Binding; Development; Event; Gene Expression; Genes; Genetic; Goals; Growth; Half-Life; Human; Immunocompromised Host; In Vitro; Institution; Laboratories; Lead; Ligase; Link; Lysine; Malignant Neoplasms; Mass Spectrum Analysis; Mediating; Melanoma Cell; Mitogen-Activated Protein Kinases; Mitotic; Modality; Modeling; Molecular; Mus; Mutagenesis; Normal Cell; Nuclear; Nude Mice; Nude Mouse Assay; Oncogenic; Outcome; Peptides; Pharmacology; Phosphorylation; Physiological; Post-Translational Protein Processing; Post-Translational Regulation; Productivity; Proteins; Regulation; Repressor Proteins; Research; Site; Small Interfering RNA; TP53 gene; Techniques; Testing; Transcription Repressor; Transgenic Organisms; Tumor Suppression; Tumor Suppressor Genes; Tumor Suppressor Proteins; Ubiquitin; Ubiquitination; Universities; Xenograft Model; Zebrafish; cancer cell; cancer therapy; cell growth; experimental study; gene product; inducible gene expression; inhibitor/antagonist; melanoma; molecular modeling; mouse model; novel; protein expression; public health relevance; reconstitution; small molecule; student training; tumor; ubiquitin-protein ligase

Project Summary/Abstract Even though Inducible cAMP Early Repressor (ICER) has the functional characteristics of a tumor suppressor, there is no genetic evidence to demonstrate that ICER is a bona fide tumor suppressor gene product. Thus, altered post-translational events might be the cause of the observed abnormalities of ICER protein expression in cancer cells. On this basis it is hypothesized that in cancer cells, ICER is deregulated by ubiquitination resulting in constitutive proteasomal degradation and/or abnormal subcellular localization. Finding alternatives to rescue endogenous ICER nuclear expression in malignant cells could lead to the development of novel cancer treatment modalities. Through this project, we will study the mechanisms and physiological consequences of ICER ubiquitination and subcellular localization. We will use melanoma as a paradigm for the study. This study will focus on two specific aims. Aim 1. Determine the functional and physiological consequences of ICER ubiquitination by characterizing the specific ubiquitination sites on ICER and ubiquitin E3 ligases using biochemistry, chromatin binding, and siRNA techniques. Aim 2. Examine the effect on tumorgenesis upon expression of “ubiquitinatable”-deficient ICER using mouse xenograft models and an established zebrafish model for melanoma. The overarching goal of this project is to determine the functional consequences of ICER post- translational modifications in cancer. The experiments described in this proposal will provide the basis for more extensive analyses of multi-component complexes associated with the regulation of ICER in cancer cells. Subsequent research will: 1) Use the zebrafish melanoma model to further characterize the molecular mechanisms of ICER ubiquitination during melanoma genesis; 2) Establish collaborative efforts to develop small-molecule compounds and small ICER-related peptides as specifics Ub-ligases inhibitors to test specific approaches to restore endogenous ICER nuclear expression in cancer cells; and 3) Study the effect of these Ub-ligase inhibitors in animal models for cancer.

项目摘要/摘要 尽管诱导型cAMP早期抑制因子(ICER)具有肿瘤的功能特征 没有遗传学证据证明ICER是一个真正的肿瘤抑制基因 产品。因此，翻译后事件的改变可能是观察到的ICER异常的原因 癌细胞中的蛋白质表达。在此基础上，假设在癌细胞中，ICER是 泛素化导致蛋白酶体的结构性降解和/或异常 亚细胞定位。寻找拯救恶性肿瘤内源性ICER核表达的替代方案 细胞可能导致新的癌症治疗方式的发展。通过这个项目，我们将研究 ICER泛素化和亚细胞定位的机制和生理后果。我们会 使用黑色素瘤作为研究的范例。这项研究将集中于两个具体目标。 目的1.通过以下方式确定ICER泛素化的功能和生理后果 用生化方法表征ICER和泛素E3连接酶上的特定泛素化位点， 染色质结合和siRNA技术。 目的2.检测肿瘤发生对“泛素化”缺陷ICER表达的影响 小鼠异种移植模型和已建立的黑色素瘤斑马鱼模型。 该项目的首要目标是确定ICER后的功能后果。 癌症中的翻译修饰。本提案中描述的实验将为更多 与癌细胞ICER调控相关的多组分复合体的广泛分析。 后续研究将：1)使用斑马鱼黑色素瘤模型进一步表征分子 ICER泛素化在黑色素瘤发生中的机制；2)建立合作努力以开发 小分子化合物和ICER相关小肽作为特异性Ub连接酶抑制剂检测特异性 恢复癌细胞内源性ICER核表达的方法；以及3)研究这些方法的影响 癌症动物模型中的UB-连接酶抑制剂。