1994 — 1997 |
Seto, Edward |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Molecular Analysis of a Metallothionein Gene Initiator @ University of Texas Hlth Sci Ctr San Ant
Extensive mutational analysis has revealed that a basal level of transcription is usually observed when all but a small region of DNA has been deleted from a eukaryotic gene promoter. These promoter elements that are necessary and sufficient for specific transcription initiation are referred to as minimal or core promoter elements. One common core element is the TATA box, located at about 30 nucleotides upstream from the initiation site of transcription. A less well-characterized, but perhaps equally important, initiator (Inr) constitutes a second such element that appears to be present in many RNA polymerase II transcribed genes. Although it has been demonstrated that, for many promoters, the integrity of the TATA element is essential for accurate and efficient transcription initiation, little is known about the role of Inr elements. The current proposed study focuses on the Inr element responsible for basal transcription of the human metallothionein IIA (hMTIIA) gene. Metallothionein are small, cysteine-rich proteins that are important in heavy metal detoxification and homeostasis. As appropriate for proteins that occupy such an essential physiological role, their expression is highly regulated. This is achieved by the presence of multiple, distinct metallothionein genes, each of which is regulated primarily at the transcriptional level. The sequence surrounding the initiation site of the hMTIIA gene exhibits strong homology to some of the previously identified Inr elements. Although expression of the hMTIIA gene is inducible by various agents, hMTIIA messenger RNAs are synthesized constitutively at high levels in most cells; therefore, its promoter provides an attractive model to study basal transcription regulation. The overall hypothesis to be evaluated is that the hMTIIA initiation sequence may be an important transcription regulatory element. The long- term goal of this project is to understand the hMTIIA Inr element, with particular emphasis on identifying cellular DNA-binding proteins that interact selectively with this Inr to regulate transcription. These studies will be of value not only in understanding the fundamentals of eukaryotic transcription regulation, but also will provide additional insights regarding the regulation of a physiologically important gene. With recombinant DNA techniques and standard promoter strength assay systems, the hMTIIA In element will be analyzed, both in its native promoter environment and after systematically modifying or linking it to heterologous promoters. The hypothesis that trans-acting factors may interact with the cis-acting hMTIIA Inr element to regulate transcription will be tested with protein-DNA binding assays. Knowledge gained from these experiments will be used to purify regulatory proteins that interact with the hMTIIA Inr and to clone the corresponding genes. Finally, the purified and clone proteins will be tested for their abilities to affect transcription initiation.
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1 |
1998 — 2002 |
Seto, Edward |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Regulation of Metallothionein Gene Expression @ University of South Florida
DESCRIPTION: Metallothioneins are small, highly conserved, cysteine-rich proteins that bind a variety of metal ions. They are found in virtually all eukaryotic organisms and are believed to have an important role in heavy metal detoxifications and homeostasis. As expected with proteins that occupy such an essential physiological role, their expression is highly regulated. This regulation is achieved by the presence of multiple, distinct metallothionein genes, the predominant metallothionein gene is hMTIIA, which accounts for 50% of all metallothioneins expressed in cultured human cells. Because of its high constitutive expression level, coupled with its ability to be further induced by a large number of exogenous stimuli, the hMTIIA gene provides an ideal system for studies of regulation of gene expression in higher eukaryotic cells. The hMTIIA promoter is quite complex. In addition to cis-acting DNA sequences that serve as binding sites for trans-acting factors such as SP1, AP1, AP2, AP4, and the glucocorticoid receptor, the hMTIIA promoter contains eight consensus metal response element sequences. A zinc finger protein with a molecular weight of 120K (ZFP120) was cloned based on its ability to interact with the metal response element overlapping the hMTIIA transcription initiation site. In this proposal, the overall hypothesis is that the hMTIIA initiation sequence is a important regulatory element, and that ZFP120 is a key hMTIIA regulatory protein for basal and Metal-induced transcription. The long-term goal of this project is to understand the underlying mechanisms that regulated hMTIIA mRNA synthesis with particular emphasis on dissecting a novel cellular DNA-binding protein, ZFP120, that interacts selectively with an hMTIIA metal response element to regulate transcription. These studies will be of value not only in understanding the fundamentals of eukaryotic transcriptional regulation, but will also provide additional insights regarding the regulation of a physiologically important gene.
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1 |
1999 — 2002 |
Seto, Edward |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Functional Analysis of Mammalian Histone Deacetylases @ University of South Florida
A key event in the regulation of eukaryotic gene expression is the post- translational modification of nucleosomal histones, which converts regions of chromosomes into transcriptionally active or inactive chromatin. The most common post-translational modifications of histones is the acetylation of epsilon-amino groups on conserved lysine residues in the histones' amino-terminal tail domains. Hyperacetylation of histones generally correlates with transcriptionally active chromatin, perhaps by increasing the accessibility of transcription factors to nucleosomal DNA, while hypoacetylation of histones correlates with transcriptional silencing. Although significant advances have been made toward understanding histone acetylation, much less is known concerning histone deacetylation. For example, during the last few years, several genes that encode histone acetyltransferase enzymes have been identified and extensively characterized. In contrast, the few mammalian proteins that have been found to possess histone deacetylase activities have not yet been characterized at all. In addition, while much effort has been devoted to understanding mechanisms that mediate histone acetylation, there are gaps in our knowledge concerning mechanisms that govern histone deacetylation. Three mammalian histone deacetylases (HDAC1, HDAC2, and HDAC3) with homology to the yeast protein RPD3 have recently been cloned. In this proposal, the overall hypothesis is that histone deacetylases play a pivotal role in the regulation of gene expression. The goal of this project is to understand the underlying mechanisms of histone deacetylation, with particular emphasis on a detailed dissection of the mammalian RPD3-related HDACs. These studies will ultimately provide important insights critical for a thorough understanding of the intricate mechanisms operation to orchestrate gene expression in mammalian cells.
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1 |
2002 — 2005 |
Seto, Edward |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Mechanisms of Transcription Factor Yin Yang 1 @ University of South Florida
DESCRIPTION (provided by applicant): Sequence-specific DNA-binding transcription factors play pivotal roles in many developmental processes and in the control of cell behavior. Yin Yang 1 (YY1) is a 41 4-amino-acid Kruppel-related zinc finger transcription factor that binds to the CGCCATNTT consensus DNA element located in promoters and enhancers of many cellular and viral genes. Like many transcription factors, YY1 requires coactivators and corepressors to function properly. Interestingly, YY1 appears to be equally effective as an activator and as a repressor depending on its relative concentration, its binding partners, and on promoter context. Although reports of the number of genes that might be regulated by YY1 are ever increasing, the exact mechanisms by which this factor regulates transcription are still unclear. The long-term goal of this proposal is aimed at obtaining a greater mechanistic understanding of how YY1 regulates transcription. Previous studies indicate that YY1 interacts with histone acetyltransferases (HATs) and with histone deacetylases (HDACs). The current proposed study focuses on a detailed analysis of the functional significance of the YY1-HATs and YY1-HDACs interactions. The hypothesis to be explored is that at least some of the effects of YY1 are a result of its contact with HATs and with HDACs, which allows the recruitment of HATs or HDACs to enzymatically modify histones and consequently affect transcription. An alternative, non-mutually exclusive hypothesis will be examined in which the interaction between HATs or HDACs and YY1 modifies the acetylation status of YY1 and consequently alters YY1s activity. Finally, genes that are regulated by YY1 in combination with HATs or HDACs in vivo will be rigorously identified and characterized. Given the long list of genes that could potentially be controlled by YY1, there is no dispute that this factor provides an attractive model for the study of transcriptional regulation and that enormous benefits can be gained by thoroughly understanding how the activity of YY1 is regulated. These studies will not only contribute fundamentally to a better understanding of the molecular biology of gene regulation but will also provide critical insights regarding the precise control of many physiologically important genes.
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1 |
2014 — 2018 |
Seto, Edward |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Targeting Sirt1 in Mantle Cell Lymphoma @ George Washington University
Mantle Cell Lymphoma; SIRT1 gene;
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0.937 |
2020 — 2021 |
Lee, Norman H Seto, Edward |
T32Activity Code Description: To enable institutions to make National Research Service Awards to individuals selected by them for predoctoral and postdoctoral research training in specified shortage areas. |
Cancer Biology Training Program (Cbtp) @ George Washington University
PROJECT SUMMARY/ ABSTRACT The overall goal of the proposed George Washington-Cancer Biology Training Program (GW- CBTP) is to educate and train scientists who will advance research on the molecular and genomic causes, progression, treatment and relapse of human malignancies. This application builds upon the formation of the George Washington Cancer Center (GWCC), which supports a vibrant cancer research community of over 150 members with a vision to create a cancer-free world through groundbreaking and rigorous research, innovative education and equitable care for all. As the only cancer training program at GW, the CBTP will reflect the major cancer research strengths of the GWCC that include Cancer Immunology and Immunotherapy, Cancer Signaling & Genomics and Cancer Epigenetics & Technology. This application seeks to appoint 3 postdoctoral and 1 predoctoral trainee annually and provide each with an individualized two year program of three elements: a discovery research project guided by expert cancer researchers and clinician investigators; a curriculum of courses and workshops on state-of-the- art approaches and emerging therapies; and career and professional development, including experience in grant writing and presentations. Key to this program is an institutional commitment to address the prominent cancer health disparities in breast, cervical, colorectal, pancreatic, liver and prostate cancers in the District of Columbia. Outstanding faculty preceptors who are all leaders in their fields and maintain outstanding track records of research productivity and mentoring of young scientists will serve as research mentors in a dual-mentor model with clinician scientists. Postdoctoral fellow appointees will have completed an M.D. or Ph.D. degree and have a clear commitment to pursuing independent careers in cancer research. Predoctoral students in their second year of graduate study in the doctoral program in Cancer Biology will be eligible for appointment. All trainees will have demonstrated a significant interest in pursuing a career in cancer-related research. The program will provide highly sought-after training experiences to transform promising young researchers into future independent cancer research scientists.
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0.937 |
2020 — 2021 |
Li, Rong Lin, Hening (co-PI) [⬀] Seto, Edward |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Regulation of Anti-Tumor Immunity by Hdac11 @ George Washington University
Project Summary/Abstract Recent developments in the field of immunotherapy clearly support the contribution of the immune system in eradicating cancer. Histone deacetylase (HDAC) inhibitors are currently employed in the treatment of many malignancies, and accumulating evidence suggests that many of the anticancer effects of HDAC inhibitors involve the immune system. Previously, there was limited information on the role of HDAC11 in immunity and cancer. We discovered that HDAC11 negatively regulates IL-10 production in antigen-presenting cells. We also found that HDAC11 is highly expressed in T lymphocytes and neutrophils and, subsequently, revealed that HDAC11 disruption in T cells is associated with an enhanced pro-inflammatory cytokine profile and effector molecule production. T cells lacking HDAC11 are less susceptible to regulatory T cell suppression in vitro, are refractory to tolerance induction in vivo, and display enhanced anti-tumor responses in transplanted mantle cell lymphoma murine models. Furthermore, HDAC11 is a multifaceted regulator of neutrophils. The absence of Hdac11 in neutrophils significantly increases cellular production of proinflammatory cytokines and promotes cell migration and phagocytic capacity. More recently, our group discovered an efficient novel activity for HDAC11, the removal of long-chain fatty acyl groups from protein lysine residues. This novel activity is >10,000-fold more efficient than its deacetylase activity. Using a syngeneic mouse-to-mouse model, we established ectopic tumors in Hdac11 wildtype and knockout (KO) mice. The growth of the syngeneic lymphoma cells in the Hdac11 KO mice was markedly inhibited, pointing toward a crucial role of HDAC11 in the tumor microenvironment. In this resubmission application, the central hypothesis is that HDAC11 reprograms anti-cancer immunity via its defatty-acylation activity and presents a potential novel drug target for cancer treatment. Our long-term goal is to develop a detailed molecular understanding of HDAC11's role in anti-tumor immunity. Results from this work will: (1) provide a better understanding of the anti-tumor behavior of HDAC11; (2) expand a functional understanding of protein lysine defatty-acylation in cancer; (3) develop better treatment strategies for cancer through targeting the lysine defatty-acylation mechanism; and (4) produce selective HDAC11 inhibitors, which will accelerate the development of new cancer treatment strategies.
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0.937 |
2021 |
Lin, Hening (co-PI) [⬀] Miller, Robert H. (co-PI) [⬀] Miller, Robert H. (co-PI) [⬀] Seto, Edward |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Design and Development of Hdac11-Specific Chemical Inhibitors For Disease Treatments @ George Washington University
Project Summary This resubmission proposal aims to elucidate the role of a histone deacetylase, HDAC11, in diseases such as multiple sclerosis (MS), and to establish HDAC11 inhibition as a potentially effective new treatment strategy for diseases including MS. MS is a chronic, immune-mediated demyelinating disease of the central nervous system. Like many autoimmune disorders, it presently has no known cure, and current drugs available for managing this disease are only effective early on and are accompanied by many adverse effects. The disease mechanism of MS remains unclear, and no effective targeted therapy is available for chronic progressive MS. Our preliminary studies show that deletion of HDAC11 ameliorates clinical symptoms in a mouse model of MS. In parallel, we discovered a novel HDAC11 enzymatic activity that is >10,000-fold more efficient than its deacetylase activity. This novel activity allows us to begin to uncover physiologic substrates of HDAC11, which in turn will help to uncover the biological mechanisms of HDAC11?s actions. One of the goals of this research is to investigate how this newly discovered enzymatic activity underlies the immune-regulatory function of HDAC11 in MS. Knowledge gained from these studies will help to further understand the disease mechanism of MS and to develop better therapeutics. Because the discovery of a novel HDAC11 activity has enabled us to develop, for the first time, HDAC11-specific inhibitors, the chief objective is to further improve these inhibitors and test whether they can be used to treat diseases such as MS in our established mouse models. Our multidisciplinary team has expertise in all aspects needed to make this project successful. Overall, the proposed studies in this application will not only yield a better understanding of HDAC11?s function in health and diseases, but may also result in a first prototype targeted therapy for the treatment of chronic progressive MS, and possibly other diseases as well.
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0.937 |