Cytokine modulated novel growth inhibitory mechanisms

细胞因子调节的新型生长抑制机制

基本信息

批准号：
7406846
负责人：
DHAN V. KALVAKOLANU
金额：
$ 25.98万
依托单位：
UNIVERSITY OF MARYLAND BALTIMORE
依托单位国家：
美国
项目类别：
财政年份：
2004
资助国家：
美国
起止时间：
2004-05-07 至 2009-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7406846
关键词：
Acids Address Amino Acids Antineoplastic Agents Antisense Oligonucleotides Antiviral Agents Apoptosis Apoptotic Binding Binding Proteins Biological Biological Assay Biological Response Modifiers Caspase Cell Death Cell Line Cell Survival Cells Cessation of life Characteristics Chimera organism Clinical Research Code Complex Cyclin Gene Data Differentiation and Growth Down-Regulation Elements Embryo Experimental Models Family Functional disorder Gene Expression Gene Targeting Genes Genetic Genetic Techniques Genetic Transcription Growth Growth Inhibitors Growth Suppressor Genes Host Defense Human Hybrids Immune response Interferons Investigation Laboratories Light Measures Mediating Mitochondria Modeling Molecular Molecular Mechanisms of Action Mutate Mutation Nuclear Protein Nuclear Proteins Numbers Oncogene Proteins Oncogenes Oncogenic Pathway interactions Permeability Physiological Play Property Protein Overexpression Proteins Regulation Regulatory Pathway Reporter Genes Research Personnel Resistance Retinoids Role STAT1 gene Signal Transduction Signaling Molecule Specificity System Therapeutic Therapeutic Agents Transcription Coactivator Tretinoin Tumor Cell Line Tumor Markers Tumor Suppressor Proteins Up-Regulation Variant Viral Vitamin A Vitamins Yeasts base cancer cell cell growth cell growth regulation cell transformation cellular targeting chimeric gene chromatin immunoprecipitation cytokine drug development gene function gene therapy immune function inhibitor/antagonist insight member mortality mouse model mutant neoplastic cell new growth novel pathogen programs promoter resistance mechanism response transcription factor tumor tumor growth viral DNA yeast two hybrid system

项目摘要

DESCRIPTION (provided by applicant): Cytokines play a central role in regulating neoplastic cell growth/n v/vo. They exert such effects either by a direct induction of growth suppressor genes in the tumor or by mounting an immune response against it. In particular, the interferon family of cytokines regulates several physiologic responses such as antiviral, antitumor, and immune functions. By interacting with other cytokines, IFNs form a large network of intercellular signaling molecules that control neoplastic cell growth and host defenses against pathogens. Among their various actions, the regulation of growth suppression by IFNs is not fully understood. In an earlier study, we demonstrated that the IFN-induced anti-tumor actions, especially apoptosis, could be synergistically augmented upon combination with retinoic acid. This vitamin-A metabolite by itself acts as a growth inhibitor in many experimental models. Some clinical studies also demonstrated the potent tumor inhibitory effects of IFN/RA. In the light of these data, it is important to understand the mechanisms of action of the molecular regulators that cause tumor growth suppression. We hypothesized that IFN/RA employs either novel gene products for inducing cell death. To identify the critical molecules involved in IFN/RA-induced apoptosis, we have taken a genetic approach that identifies genes on the basis of their functions. Here, we have characterized a novel gene product, (gene associated with Retinoid-lnterferon induced Mortality-19 (GRIM-19), which induces apoptosis. The anti-oncogenic effects of GRIM-19 were further highlighted in our recent studies, where its apoptotic functions were suppressed by DNA viral oncoproteins. GRIM-19-expression appears to be inhibited in some human tumors. These characteristics indicate its potent anti-oncogenic characteristics. To gain a better insight into the mechanisms of action, we have used a yeast-2-hybrid screen and identified Signal Transducing Activator of Transcription-3 (STAT3) as a GRIM-19 binding protein. Several recent studies have shown that STAT3, an otherwise dormant signal-regulated transcription factor, is constitutively activated in human tumors. A number of viral and cellular oncoproteins constitutively stimulate its activity to promote cell survival. Based on our preliminary observations, we have hypothesized that GRIM-19 inhibits STAT3-regulated transcription. In this proposal we will investigate the mechanisms of GRIM-19 induced inhibitory effects on tumor cell growth. In particular, we will study the anti-oncogenic effects of GRIM-19 on a constitutively active STAT3 variant, and an oncogenic Src, which uses STAT3 for promoting cell growth. We will also define the critical domains that mediate GRIM-19:STAT3 interactions. Using chromatin immunoprecipitation (CHIP) assays, STAT3-regulated reporter genes and mutant cell lines lacking STAT3, we will investigate the mechanisms of the anti-STAT3 effects of GRIM-19. GRIM-19 may be: 1) a novel tumor suppressor; 2) serve as a marker for the tumor response to therapeutic agents 3) inhibit several other cancer cells by participating in other growth suppressive pathways; 4) be useful in gene therapy once its mode of action has been defined. Thus, an understanding of GRIM-19 action will further help in defining the tumor cell-specific dysfunctions that ablate this new growth regulatory pathway. In summary, the studies proposed in this application will uncover a novel mechanism of cell growth regulation employed by a newly discovered anti-oncogenic protein.

描述（由申请人提供）：细胞因子在调节肿瘤细胞生长/N V/VO中起着核心作用。它们通过直接诱导肿瘤中生长抑制基因或对其进行免疫反应来发挥这种作用。特别是，细胞因子的干扰素家族调节了几种生理反应，例如抗病毒，抗肿瘤和免疫功能。通过与其他细胞因子相互作用，IFNS形成了控制肿瘤细胞生长和针对病原体的宿主防御的大型细胞间信号分子网络。在他们的各种行动中，IFN对生长抑制的调节尚未完全理解。在较早的研究中，我们证明了IFN诱导的抗肿瘤作用，尤其是凋亡，可以在与视黄酸结合使用后协同增强。在许多实验模型中，这种维生素-A代谢产物本身就是一种生长抑制剂。一些临床研究还证明了IFN/RA的有效肿瘤抑制作用。鉴于这些数据，重要的是要了解引起肿瘤生长抑制的分子调节剂的作用机理。我们假设IFN/RA使用任何一种新型基因产物来诱导细胞死亡。为了鉴定IFN/RA诱导的凋亡中涉及的关键分子，我们采用了一种遗传方法，该方法根据其功能鉴定基因。在这里，我们表征了一种新型的基因产物（与类视感螺旋菌相关的基因诱导死亡率19（Grim-19），诱导凋亡。在我们最近的研究中，GRIM-19的抗癌作用进一步强调了，在我们最近的研究中，它的凋亡功能被DNA病毒抗蛋白的表达方式抑制。有效的抗疾病特征。根据我们的初步观察，刺激其活性以促进细胞的生存。在此提案中，我们将研究GRIM-19的机制对肿瘤细胞生长的抑制作用。特别是，我们将研究GRIM-19对组成型活性STAT3变体的抗疾病作用，以及使用STAT3促进细胞生长的致癌SRC。我们还将定义介导Grim-19：STAT3相互作用的关键领域。使用染色质免疫沉淀（CHIP）测定，STAT3调节的报告基因和缺乏STAT3的突变细胞系，我们将研究Grim-19的抗STAT3效应的机制。 Grim-19可能是：1）一种新型的肿瘤抑制剂； 2）作为对治疗剂的肿瘤反应的标志物3）通过参与其他生长抑制途径来抑制其他几个癌细胞； 4）一旦定义了其作用方式，就可以在基因治疗中有用。因此，对Grim-19的作用的理解将进一步有助于定义肿瘤细胞特异性功能障碍，从而消除这种新的生长调节途径。总而言之，在本应用中提出的研究将发现新发现的抗结合蛋白采用的新型细胞生长调节机制。