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Role of Notch Receptors in Hematologic Malignancies. Cells 2020; 10:cells10010016. [PMID: 33374160 PMCID: PMC7823720 DOI: 10.3390/cells10010016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 12/18/2020] [Accepted: 12/22/2020] [Indexed: 02/06/2023] Open
Abstract
Notch receptors are single-pass transmembrane proteins that play a critical role in cell fate decisions and have been implicated in the regulation of many developmental processes. The human Notch family comprises of four receptors (Notch 1 to 4) and five ligands. Their signaling can regulate extremely basic cellular processes such as differentiation, proliferation and death. Notch is also involved in hematopoiesis and angiogenesis, and increasing evidence suggests that these genes are involved and frequently deregulated in several human malignancies, contributing to cell autonomous activities that may be either oncogenic or tumor suppressive. It was recently proposed that Notch signaling could play an active role in promoting and sustaining a broad spectrum of lymphoid malignancies as well as mutations in Notch family members that are present in several disorders of T- and B-cells, which could be responsible for altering the related signaling. Therefore, different Notch pathway molecules could be considered as potential therapeutic targets for hematological cancers. In this review, we will summarize and discuss compelling evidence pointing to Notch receptors as pleiotropic regulators of hematologic malignancies biology, first describing the physiological role of their signaling in T- and B-cell development and homeostasis, in order to fully understand the pathological alterations reported.
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Study of expression analysis of SIRT4 and the coordinate regulation of bovine adipocyte differentiation by SIRT4 and its transcription factors. Biosci Rep 2018; 38:BSR20181705. [PMID: 30442871 PMCID: PMC6294651 DOI: 10.1042/bsr20181705] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 11/04/2018] [Accepted: 11/15/2018] [Indexed: 11/17/2022] Open
Abstract
Sirtuins, NAD+-dependent deacylases and ADP-ribosyltransferases, are critical regulators of metabolism involved in many biological processes, and are involved in mediating adaptive responses to the cellular environment. SIRT4 is a mitochondrial sirtuin and has been shown to play a critical role in maintaining insulin secretion and glucose homeostasis. As a regulator of lipid homeostasis, SIRT4 can repress fatty acid oxidation and promote lipid anabolism in nutrient-replete conditions. Using real-time quantitative PCR (qPCR) to explore the molecular mechanisms of transcriptional regulation of bovine SIRT4 during adipocyte differentiation, we found that bovine SIRT4 is expressed at high levels in bovine subcutaneous adipose tissue. SIRT4 knockdown led to decreased expression of adipogenic differentiation marker genes during adipocyte differentiation. The core promoter of bovine SIRT4 was identified in the −402/−60 bp region of the cloned 2-kb fragment containing the 5′-regulatory region. Binding sites were identified in this region for E2F transcription factor-1 (E2F1), CCAAT/enhancer-binding protein β (CEBPβ), homeobox A5 (HOXA5), interferon regulatory factor 4 (IRF4), paired box 4 (PAX4), and cAMP responsive element-binding protein 1 (CREB1) by using Electrophoretic mobility shift assay (EMSA) and luciferase reporter gene assay. We also found that E2F1, CEBPβ, and HOXA5 transcriptionally activate SIRT4 expression, whereas, IRF4, PAX4, and CREB1 transcriptionally repress SIRT4 expression. We further verified that SIRT4 knockdown could affect the ability of these transcription factors (TFs) to regulate the differentiation of bovine adipocytes. In conclusion, our results shed light on the mechanisms underlying the transcriptional regulation of SIRT4 expression in bovine adipocytes.
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Avgan N, Sutherland HG, Lea RA, Spriggens LK, Haupt LM, Shum DHK, Griffiths LR. A CREB1 Gene Polymorphism (rs2253206) Is Associated with Prospective Memory in a Healthy Cohort. Front Behav Neurosci 2017; 11:86. [PMID: 28559802 PMCID: PMC5432533 DOI: 10.3389/fnbeh.2017.00086] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 04/25/2017] [Indexed: 11/18/2022] Open
Abstract
Prospective memory (PM) is generally defined as remembering to perform intended actions in the future and is important for functioning in daily life. Cyclic adenosine monophosphate (cAMP) responsive element binding protein 1 (CREB1) plays an important role in cognitive functions. In this study, we hypothesized that genetic variation in the CREB1 gene is associated with PM. We genotyped a CREB1 promoter polymorphism rs2253206 and tested it for association with PM in 619 healthy subjects. PM performance was measured using the Prospective and Retrospective Memory Questionnaire (PRMQ), the Comprehensive Assessment of Prospective Memory (CAPM), and the Memory for Intentions Screening Test (MIST). Generalized linear model analysis was conducted for each PM test independently using different inheritance models to identify any associations (p < 0.05). After multiple testing adjustments, a significant association was found between the rs2253206 genotype and PM performance for CAPM instrumental activities of daily living measure (p = 0.016). These results suggest that the rs2253206 polymorphism in the CREB1 gene locus is associated with PM in healthy individuals and contributes to knowledge on the genetics of this particular type of memory.
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Affiliation(s)
- Nesli Avgan
- Genomics Research Centre, Chronic Disease and Ageing, Institute of Health and Biomedical Innovation, School of Biomedical Sciences, Queensland University of Technology, BrisbaneQLD, Australia
| | - Heidi G Sutherland
- Genomics Research Centre, Chronic Disease and Ageing, Institute of Health and Biomedical Innovation, School of Biomedical Sciences, Queensland University of Technology, BrisbaneQLD, Australia
| | - Rodney A Lea
- Genomics Research Centre, Chronic Disease and Ageing, Institute of Health and Biomedical Innovation, School of Biomedical Sciences, Queensland University of Technology, BrisbaneQLD, Australia
| | - Lauren K Spriggens
- Menzies Health Institute Queensland and School of Applied Psychology, Griffith University, Gold CoastQLD, Australia
| | - Larisa M Haupt
- Genomics Research Centre, Chronic Disease and Ageing, Institute of Health and Biomedical Innovation, School of Biomedical Sciences, Queensland University of Technology, BrisbaneQLD, Australia
| | - David H K Shum
- Menzies Health Institute Queensland and School of Applied Psychology, Griffith University, Gold CoastQLD, Australia
| | - Lyn R Griffiths
- Genomics Research Centre, Chronic Disease and Ageing, Institute of Health and Biomedical Innovation, School of Biomedical Sciences, Queensland University of Technology, BrisbaneQLD, Australia
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Ma J, Wang L, Yang Y, Qiao Z, Fang D, Qiu X, Yang X, Zhu X, He J, Pan H, Ban B, Zhao Y, Sui H. GNB3 and CREB1 gene polymorphisms combined with negative life events increase susceptibility to major depression in a Chinese Han population. PLoS One 2017; 12:e0170994. [PMID: 28225778 PMCID: PMC5321408 DOI: 10.1371/journal.pone.0170994] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2016] [Accepted: 01/13/2017] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Major depression (MD) is caused by a combination of genetic and environmental factors. In this study we investigated the interaction of variations in the G-protein beta 3 subunit (GNB3) and cAMP response element binding protein 1 (CREB1) genes with negative life events in the pathogenesis of MD. One GNB3 polymorphism (rs5443) and four CREB1 polymorphisms (rs2253206, rs2551941, rs6740584, rs11904814) were investigated based on known associations with MD. METHODS 512 patients with MD and 513 control subjects were genotyped. The frequency and severity of negative life events were measured by the Life Events Scale (LES). Gene-environment interactions (G×E) were assessed using the generalized multifactor dimensionality reduction (GMDR) method. RESULTS Differences in GNB3 rs5443 allele frequencies and genotype distributions were observed between MD patients and controls. Significant G×E interactions were detected between negative life events and genotypic variation of all five single nucleotide polymorphisms (SNPs). Individuals carrying the T- allele of rs5443 (CC), A- allele of rs2253206 (GG), T- allele of rs2551941 (AA), C- allele of rs6740584 (TT) or G- allele of rs11904814 (TT) conferred susceptibility to MD in subjects only exposed to high-negative life events. However, individuals with the T+ allele of rs5443 (CT, TT) were susceptible to MD when exposed to low negative life events. CONCLUSIONS Interactions between GNB3, CREB1 and negative life events were revealed. Further evidence is provided about the role of the environment in genetic vulnerability to MD.
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Affiliation(s)
- Jingsong Ma
- Psychology Department of the Public Health Institute of Harbin Medical University, Harbin, China
| | - Lin Wang
- Psychology Department of the Public Health Institute of Harbin Medical University, Harbin, China
| | - Yanjie Yang
- Psychology Department of the Public Health Institute of Harbin Medical University, Harbin, China
- * E-mail: (YJY); (ZXQ)
| | - Zhengxue Qiao
- Psychology Department of the Public Health Institute of Harbin Medical University, Harbin, China
- * E-mail: (YJY); (ZXQ)
| | - Deyu Fang
- Northwestern University Feinberg School of Medicine, Evanston, Illinois, United States of America
| | - Xiaohui Qiu
- Psychology Department of the Public Health Institute of Harbin Medical University, Harbin, China
| | - Xiuxian Yang
- Psychology Department of the Public Health Institute of Harbin Medical University, Harbin, China
| | - Xiongzhao Zhu
- Medical Psychological Institute of the Second Xiangya Hospital of Central South University, Changsha, China
| | - Jincai He
- The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Hui Pan
- Peking union Medical College Hospital, Beijing, China
| | - Bo Ban
- Affiliated Hosptial of Jining Medical University, Jining, China
| | - Yan Zhao
- The Second Affiliated Hosptial of Harbin Medical University, Harbin, China
| | - Hong Sui
- Psychology Department of the Public Health Institute of Harbin Medical University, Harbin, China
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Li Y, Chen D, Li Y, Jin L, Liu J, Su Z, Qi Z, Shi M, Jiang Z, Ni L, Yang S, Gui Y, Mao X, Chen Y, Lai Y. Oncogenic cAMP responsive element binding protein 1 is overexpressed upon loss of tumor suppressive miR-10b-5p and miR-363-3p in renal cancer. Oncol Rep 2016; 35:1967-78. [PMID: 26796749 DOI: 10.3892/or.2016.4579] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Accepted: 09/09/2015] [Indexed: 11/05/2022] Open
Abstract
Renal cell carcinoma (RCC) is the most common kidney cancer in adults and has a poor prognosis. cAMP responsive element binding protein 1 (CREB1) is a proto‑oncogenic transcription factor involved in malignancies of various organs. However, its functional role(s) have not yet been elucidated in RCC. We investigated the expression pattern, function and regulation of CREB1 in RCC. CREB1 was overexpressed in the RCC tissues and cell lines. Downregulation of CREB1 inhibited RCC tumorigenesis by affecting cell proliferation, migration and apoptosis. Multiple computational algorithms predicted that the 3'‑untranslated region (3'‑UTR) of human CREB1 mRNA is a target for miR‑10b‑5p and miR‑363‑3p. Luciferase reporter assay, qPCR and western blot analysis confirmed that miR‑10b‑5p and miR‑363‑3p bind directly to the 3'‑UTR of CREB1 mRNA and inhibit mRNA and protein expression of CREB1. qPCR data also revealed a significantly lower expression of miR‑10b‑5p and miR‑363‑3p in RCC tissues. Introduction of miR‑10b‑5p and miR‑363‑3p mimics led to suppressed expression of CREB1 and inhibited cell proliferation, migration and apoptosis reduction. Taken together, we propose that CREB1 is an oncogene in RCC and that upregulation of CREB1 by loss of tumor suppressive miR‑10b‑5p and miR‑363‑3p plays an important role in the tumorigenesis of RCC.
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Affiliation(s)
- Yifan Li
- Department of Urology, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Duqun Chen
- Department of Urology, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Yuchi Li
- The Guangdong and Shenzhen Key Laboratory of Male Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Lu Jin
- Department of Urology, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Jiaju Liu
- Department of Urology, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Zhengming Su
- Department of Urology, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Zhengyu Qi
- The Guangdong and Shenzhen Key Laboratory of Male Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Min Shi
- The Guangdong and Shenzhen Key Laboratory of Male Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Zhimao Jiang
- The Guangdong and Shenzhen Key Laboratory of Male Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Liangchao Ni
- The Guangdong and Shenzhen Key Laboratory of Male Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Shangqi Yang
- Department of Urology, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Yaoting Gui
- The Guangdong and Shenzhen Key Laboratory of Male Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Xiangming Mao
- Department of Urology, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
| | - Yun Chen
- Department of Ultrasound Division, Peking University Shenzhen Hospital, Shenzhen, Guangdong 518036, P.R. China
| | - Yongqing Lai
- Department of Urology, Peking University Shenzhen Hospital, Institute of Urology of Shenzhen PKU‑HKUST Medical Center, Shenzhen, Guangdong 518036, P.R. China
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Cai C, Chen L, Jiang X, Lu X. Modeling signal transduction from protein phosphorylation to gene expression. Cancer Inform 2014; 13:59-67. [PMID: 25392684 PMCID: PMC4216050 DOI: 10.4137/cin.s13883] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 05/04/2014] [Accepted: 05/04/2014] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Signaling networks are of great importance for us to understand the cell’s regulatory mechanism. The rise of large-scale genomic and proteomic data, and prior biological knowledge has paved the way for the reconstruction and discovery of novel signaling pathways in a data-driven manner. In this study, we investigate computational methods that integrate proteomics and transcriptomic data to identify signaling pathways transmitting signals in response to specific stimuli. Such methods can be applied to cancer genomic data to infer perturbed signaling pathways. METHOD We proposed a novel Bayesian Network (BN) framework to integrate transcriptomic data with proteomic data reflecting protein phosphorylation states for the purpose of identifying the pathways transmitting the signal of diverse stimuli in rat and human cells. We represented the proteins and genes as nodes in a BN in which edges reflect the regulatory relationship between signaling proteins. We designed an efficient inference algorithm that incorporated the prior knowledge of pathways and searched for a network structure in a data-driven manner. RESULTS We applied our method to infer rat and human specific networks given gene expression and proteomic datasets. We were able to effectively identify sparse signaling networks that modeled the observed transcriptomic and proteomic data. Our methods were able to identify distinct signaling pathways for rat and human cells in a data-driven manner, based on the facts that rat and human cells exhibited distinct transcriptomic and proteomics responses to a common set of stimuli. Our model performed well in the SBV IMPROVER challenge in comparison to other models addressing the same task. The capability of inferring signaling pathways in a data-driven fashion may contribute to cancer research by identifying distinct aberrations in signaling pathways underlying heterogeneous cancers subtypes.
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Affiliation(s)
- Chunhui Cai
- Department of Biomedical Informatics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Lujia Chen
- Department of Biomedical Informatics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Xia Jiang
- Department of Biomedical Informatics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Xinghua Lu
- Department of Biomedical Informatics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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Failmezger H, Fröhlich H, Tresch A. Unsupervised automated high throughput phenotyping of RNAi time-lapse movies. BMC Bioinformatics 2013; 14:292. [PMID: 24090185 PMCID: PMC3851277 DOI: 10.1186/1471-2105-14-292] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 07/29/2013] [Indexed: 02/01/2023] Open
Abstract
Background Gene perturbation experiments in combination with fluorescence time-lapse cell imaging are a powerful tool in reverse genetics. High content applications require tools for the automated processing of the large amounts of data. These tools include in general several image processing steps, the extraction of morphological descriptors, and the grouping of cells into phenotype classes according to their descriptors. This phenotyping can be applied in a supervised or an unsupervised manner. Unsupervised methods are suitable for the discovery of formerly unknown phenotypes, which are expected to occur in high-throughput RNAi time-lapse screens. Results We developed an unsupervised phenotyping approach based on Hidden Markov Models (HMMs) with multivariate Gaussian emissions for the detection of knockdown-specific phenotypes in RNAi time-lapse movies. The automated detection of abnormal cell morphologies allows us to assign a phenotypic fingerprint to each gene knockdown. By applying our method to the Mitocheck database, we show that a phenotypic fingerprint is indicative of a gene’s function. Conclusion Our fully unsupervised HMM-based phenotyping is able to automatically identify cell morphologies that are specific for a certain knockdown. Beyond the identification of genes whose knockdown affects cell morphology, phenotypic fingerprints can be used to find modules of functionally related genes.
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Affiliation(s)
- Henrik Failmezger
- Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, 50829, Cologne, Germany.
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Cheng JC, Esparza S, Sandoval S, Shankar D, Fu C, Sakamoto KM. Potential role of CREB as a prognostic marker in acute myeloid leukemia. Future Oncol 2008; 3:475-80. [PMID: 17661722 DOI: 10.2217/14796694.3.4.475] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The cAMP response element binding protein (CREB) is a leucine zipper transcription factor that regulates genes responsible for cell proliferation, differentiation and survival. CREB is overexpressed in the bone marrow from most patients with acute leukemia. Overexpression of CREB occurs both at the protein and at the transcript levels and is associated with gene amplification in leukemic blast cells. Higher levels of CREB correlate with a less favorable prognosis in a small cohort of adult patients with acute myeloid leukemia. In one study, patients whose bone marrow over-expresses CREB had an increased risk of relapse and decreased event-free survival. Mice that overexpress CREB in myeloid cells develop a myeloproliferative/myelodysplastic syndrome. These findings suggest that CREB plays an important role in the pathogenesis of acute leukemia and is a potential biomarker of disease.
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Affiliation(s)
- Jerry C Cheng
- Jonsson Comprehensive Cancer Center, Division of Hematology/Oncology, Department of Pediatrics, Gwynne Hazen Cherry Memorial Laboratories, Los Angeles, CA 90095-1781, USA.
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Shankar DB, Cheng JC, Sakamoto KM. Role of cyclic AMP response element binding protein in human leukemias. Cancer 2005; 104:1819-24. [PMID: 16196046 DOI: 10.1002/cncr.21401] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Acute myeloid leukemia (AML) in adults has a 20% 5-year disease-free survival despite treatment with aggressive cytotoxic chemotherapy. Previous work from our laboratory demonstrated that the majority of patients with acute lymphoid and myeloid leukemia overexpress CREB in the bone marrow. CREB overexpression is associated with poor initial outcome of clinical disease in AML patients. CREB is a transcription factor that functions in glucose homeostasis, growth-factor-dependent cell survival, and memory. Signaling by hematopoietic growth factors, such as GM-CSF, results in activation of CREB and up-regulation of CREB target genes. To study its role in hematopoiesis, we overexpressed CREB in leukemia cell lines and in mice. CREB overexpression resulted in increased survival and proliferation of myeloid cells and blast-transformation of bone marrow progenitor cells from transgenic mice expressing CREB in the myeloid lineage. CREB transgenic mice also develop myeloproliferative disease after 1 year. Thus, CREB acts as a protooncogene to regulate hematopoiesis and contributes to the leukemia phenotype. Our results suggest that CREB-dependent pathways may serve as targets for directed therapies in leukemia in the future.
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Affiliation(s)
- Deepa B Shankar
- Department of Pediatrics, Division of Hematology/Oncology, Gwynne Hazen Cherry Memorial Laboratories, and Mattel Children's Hospital, Jonsson Comprehensive Cancer Center, Los Angeles, California, USA
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Shankar DB, Cheng JC, Kinjo K, Federman N, Moore TB, Gill A, Rao NP, Landaw EM, Sakamoto KM. The role of CREB as a proto-oncogene in hematopoiesis and in acute myeloid leukemia. Cancer Cell 2005; 7:351-62. [PMID: 15837624 DOI: 10.1016/j.ccr.2005.02.018] [Citation(s) in RCA: 193] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2004] [Revised: 11/24/2004] [Accepted: 02/24/2005] [Indexed: 11/21/2022]
Abstract
CREB is a transcription factor that functions in glucose homeostasis, growth factor-dependent cell survival, and memory. In this study, we describe a role of CREB in human cancer. CREB overexpression is associated with increased risk of relapse and decreased event-free survival. CREB levels are elevated in blast cells from patients with acute myeloid leukemia. To understand the role of CREB in leukemogenesis, we studied the biological consequences of CREB overexpression in primary human leukemia cells, leukemia cell lines, and transgenic mice. Our results demonstrate that CREB promotes abnormal proliferation and survival of myeloid cells in vitro and in vivo through upregulation of specific target genes. Thus, we report that CREB is implicated in myeloid cell transformation.
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Affiliation(s)
- Deepa B Shankar
- Division of Hematology/Oncology, Department of Pediatrics, Gwynne Hazen Cherry Memorial Laboratories and Mattel Children's Hospital, Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA
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Crans-Vargas HN, Landaw EM, Bhatia S, Sandusky G, Moore TB, Sakamoto KM. Expression of cyclic adenosine monophosphate response-element binding protein in acute leukemia. Blood 2002; 99:2617-9. [PMID: 11895805 DOI: 10.1182/blood.v99.7.2617] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cyclic adenosine monophosphate response-element binding protein (CREB) is a nuclear protein that regulates expression of genes that control cell proliferation, differentiation, and survival. To analyze CREB expression in leukemia cells, we conducted Western blot analysis of bone marrow cells obtained from patients with acute lymphoblastic leukemia, patients with acute myeloid leukemia, and patients without active leukemia. CREB was expressed at a higher frequency in bone marrow cells from patients with acute lymphoid or myeloid leukemia than in patients with leukemia remission or without leukemia. Our results indicate that CREB expression could be a useful marker for leukemia in patients with acute disease and suggest a role for CREB in leukemogenesis.
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Affiliation(s)
- Heather N Crans-Vargas
- Department of Pediatrics, Division of Hematology-Oncology, Gwynne-Hazen Cherry Memorial Laboratories, University of California Los Angeles (UCLA), Los Angeles, CA 90095-2752, USA
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12
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Fentzke RC, Korcarz CE, Lang RM, Lin H, Leiden JM. Dilated cardiomyopathy in transgenic mice expressing a dominant-negative CREB transcription factor in the heart. J Clin Invest 1998; 101:2415-26. [PMID: 9616213 PMCID: PMC508831 DOI: 10.1172/jci2950] [Citation(s) in RCA: 197] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Idiopathic-dilated cardiomyopathy (IDC) is a common primary myocardial disease of unknown etiology characterized by progressive biventricular failure, cardiac dilatation, and premature mortality. Here we show that transgenic mice expressing a dominant-negative form of the CREB transcription factor (CREBA133) under the control of the cardiac myocyte-specific alpha-MHC promoter develop dilated cardiomyopathy that closely resembles many of the anatomical, physiological, and clinical features of human IDC. Between 2 and 20 wk of age, these mice develop four chamber cardiac dilatation, decreased systolic and diastolic left ventricular function, and attenuated contractile responses to the beta-adrenergic agonist, isoproterenol. Histologically, the CREBA133 hearts demonstrated both atrophic and hypertrophied fibers as well as significant interstitial fibrosis. These anatomical and hemodynamic changes were associated with hepatic congestion and peripheral edema, intracardiac thrombi, and premature mortality. Taken together, these results implicate CREB as an important regulator of cardiac myocyte function and provide a genetic model of dilated cardiomyopathy which should facilitate studies of both the pathogenesis and therapy of this clinically important disorder.
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Affiliation(s)
- R C Fentzke
- Department of Medicine, University of Chicago, Chicago, Illinois 60637, USA
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Yin MJ, Paulssen EJ, Seeler JS, Gaynor RB. Protein domains involved in both in vivo and in vitro interactions between human T-cell leukemia virus type I tax and CREB. J Virol 1995; 69:3420-32. [PMID: 7745688 PMCID: PMC189054 DOI: 10.1128/jvi.69.6.3420-3432.1995] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Gene expression from the human T-cell leukemia virus type I (HTLV-I) long terminal repeat (LTR) is mediated by three cis-acting regulatory elements known as 21-bp repeats and the transactivator protein Tax. The 21-bp repeats can be subdivided into three motifs known as A, B, and C, each of which is important for maximal gene expression in response to Tax. The B motif contains nucleotide sequences known as a cyclic AMP response element (CRE) or tax-response element which binds members of the ATF/CREB family of transcription factors. Though mutations of this element in the HTLV-I LTR eliminate tax activation, Tax will not activate most other promoters containing these CRE sites. In this study, we investigated the mechanism by which Tax activates gene expression in conjunction with members of the ATF/CREB family. We found that Tax enhanced the binding of one member of the ATF/CREB family, CREB 1, to each of the three HTLV-I LTR 21-bp repeats but not another member designated CRE-BP1 or CREB2. Tax enhanced the binding of CREB1 to nonpalindromic CRE binding sites such as those found in the HTLV-I LTR, but Tax did not enhance the binding of CREB1 to palindromic CRE binding sites such as found in the somatostatin promoter. This finding may help explain the failure of Tax to activate promoters containing consensus CRE sites. These studies were extended by use of the mammalian two-hybrid system. Tax was demonstrated to interact directly with CREB1 but not with other bZIP proteins, including CREB2 and Jun. Site-directed mutagenesis of both Tax and CREB1 demonstrated that the amino terminus of Tax and both the basic and the leucine zipper regions of CREB1 were required for direct interactions between these proteins both in vivo and in vitro. This interaction occurred in vivo and thus did not require the presence of the HTLV-I 21-bp repeats, as previously suggested. These results define the domains required for interaction between Tax and CREB that are likely critical for the activation of HTLV-I gene expression.
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Affiliation(s)
- M J Yin
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas 75235-8594, USA
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Habener JF, Miller CP, Vallejo M. cAMP-dependent regulation of gene transcription by cAMP response element-binding protein and cAMP response element modulator. VITAMINS AND HORMONES 1995; 51:1-57. [PMID: 7483321 DOI: 10.1016/s0083-6729(08)61037-7] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- J F Habener
- Laboratory of Molecular Endocrinology, Massachusetts General Hospital, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts 02114, USA
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15
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Shaw MA, Atkinson S, Dockrell H, Hussain R, Lins-Lainson Z, Shaw J, Ramos F, Silveira F, Mehdi SQ, Kaukab F. An RFLP map for 2q33-q37 from multicase mycobacterial and leishmanial disease families: no evidence for an Lsh/Ity/Bcg gene homologue influencing susceptibility to leprosy. Ann Hum Genet 1993; 57:251-71. [PMID: 7910002 DOI: 10.1111/j.1469-1809.1993.tb00899.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The mycobacterial diseases leprosy and tuberculosis (TB) and the leishmaniases are characterized by a wide spectrum of disease phenotypes, and by the fact that the majority of individuals exposed to the causative organisms Mycobacterium leprae, M. tuberculosis and Leishmania sp. become infected but do not present with clinical disease. In order to determine whether a human homologue to the murine macrophage resistance gene Lsh/Ity/Bcg influences susceptibility to human disease, multicase families for all three diseases have been collected, and linkage analysis performed using a panel of markers in the region of human chromosome 2q33-q37 known to be conserved with the Lsh/Ity/Bcg-containing region of murine chromosome 1. Because of the paucity of available polymorphic markers/linkage information for 2q33-q37, data from 35 multicase leprosy, TB and visceral leishmaniasis families (310 individuals) were first pooled to produce a detailed RFLP map of the region. Peak LOD scores well in excess of 3 were observed for linkage between adjacent pairs of a more proximal (2q33-q35) set of markers CRYGP1, MAP2, FN1, TNP1, VIL1 and DES, and between adjacent pairs of a more distal (2q35-q37) set COL6A3, D2S55 and D2S3. These peak LOD scores and the corresponding values for theta were used in the MAP92 program to generate a multiple two-point map with gene order/map intervals (cM) of: CRYGP1-4.65-MAP2-3.45-FN1-5.95-TNP1-3.41-VIL1-3. 01- DES-20.14-COL6A-10.91-D2S55-3.67-D2S3. Although local support for the placement of loci in this order was weak (LOD < 2, except for DES-COL6A3 where LOD = 6.02), the map is consistent with the gene order for those loci (Cryg, Fn-1, Tp-1, Vil, Des, Col6a3) previously mapped in the mouse. Data from 17 multicase leprosy families (149 individuals) were further analysed for linkage between a putative disease susceptibility locus (DSL) controlling susceptibility to leprosy per se and each of the marker loci. Assuming 100% penetrance for the susceptibility allele, no positive LOD score was obtained for linkage between the DSL and any of the marker genes. Instead, the data provide convincing evidence (LOD scores < -2) that a DSL does not fall within 10-20 cM of CRYGP1, MAP2, TNP1, VIL1, DES or D2S55, or within 5-10 cM of FN1, COL6A3 or D2S3. This effectively excludes a putative DSL controlling susceptibility to leprosy per se from the entire region 2q33-q37.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- M A Shaw
- Department of Medicine, University of Cambridge Clinical School, UK
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16
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Lee WS, Wells RG, Sabbag RV, Mohandas TK, Hediger MA. Cloning and chromosomal localization of a human kidney cDNA involved in cystine, dibasic, and neutral amino acid transport. J Clin Invest 1993; 91:1959-63. [PMID: 8486766 PMCID: PMC288191 DOI: 10.1172/jci116415] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We have recently cloned, sequenced, and characterized a rat kidney cDNA (D2) that stimulates cystine as well as dibasic and neutral amino acid transport. In order to evaluate the role of this protein in human inherited diseases such as cystinuria, we have isolated a human D2 clone (D2H) by low stringency screening of a human kidney cDNA library using the radiolabeled D2 insert as a probe. The D2H cDNA is 2284 nucleotides long and encodes a 663 amino acid protein that is 80% identical to the rat D2 amino acid sequence and 86% to that of the rabbit homologue rBAT. Microinjection of in vitro transcribed D2H cRNA into Xenopus oocytes induced uptake of cystine as well as dibasic and neutral amino acids in a pattern similar to that of rat D2 and rabbit rBAT. Both neutral and dibasic amino acids inhibited the D2H-induced uptake of cystine. Northern blot analysis demonstrated that D2H, like D2 and rBAT, is expressed strongly in the kidney and intestine. Southern blot analysis of genomic DNA from a panel of mouse-human somatic cell hybrids showed that the human gene for D2H resides on chromosome 2.
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Affiliation(s)
- W S Lee
- Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115
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17
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Abstract
The gene CREB1 encoding the cyclic AMP response element DNA binding protein was previously assigned to human 2q32.3-q34. In this study, a panel of 207 backcross mice made between C57BL/10ScSn (=B10) females and (B10 x B10.L-Lsh)F1 males were used to map Creb-1 with respect to Cryg and Lsh/Vil on mouse chromosome 1. A reverse-transcribed, polymerase chain reaction-amplified cDNA probe covering bp 39 to 554 of the human sequence identified restriction fragment length polymorphisms with 7/18 restriction endonucleases used to digest whole genomic mouse DNA from the parental strains. BglII and DraI RFLPs for Creb-1 were scored on a subpanel of 16/207 known recombinants between Cryg and Lsh/Vil, yielding 2/16 recombinants between Cryg and Creb-1 and 14/16 recombinants between Creb-1 and Lsh/Vil. The 16/207 recombinants observed between Lsh/Vil and Cryg provide an estimated recombination frequency of 0.077 +/- 0.019, equivalent to a map distance of 7.7 +/- 1.9 cM. This is in good agreement with previously published map distances. The number of recombinants observed between Creb-1 and the other markers place Creb-1 approximately 1 cM distal to Cryg and 7 cM proximal to Lsh/Vil.
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Affiliation(s)
- C H Barton
- University of Cambridge Clinical School, Department of Medicine, Addenbrooke's Hospital, Cambridge, United Kingdom
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18
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Cole TJ, Copeland NG, Gilbert DJ, Jenkins NA, Schütz G, Ruppert S. The mouse CREB (cAMP responsive element binding protein) gene: structure, promoter analysis, and chromosomal localization. Genomics 1992; 13:974-82. [PMID: 1387109 DOI: 10.1016/0888-7543(92)90010-p] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In this paper we report the isolation and characterization of the mouse CREB gene. It is composed of 11 exons and 10 introns and spans a region of 70 kb. BR-A and BR-B, the two alpha-helical regions of the proposed basic DNA binding domain of CREB, are encoded separately on exons 10 and 11. The mouse CREB gene is expressed from a promoter that is situated in a CpG island. The promoter contains no TATA or CCAAT box homologies but has a number of putative binding sites for the acidic transcriptional activator Sp1 and a 9/11 match with the initiator region. Transcriptional start site mapping identified five major start sites spread over at least 41 nucleotides. Northern blot analysis indicated that expression of the CREB gene is almost ubiquitous with expression at differing levels of multiple transcripts. Testis expressed a predominant RNA species of approximately 1.6 kb. The CREB gene was found to be single copy in the mouse and well conserved through evolution. Finally Creb-1, the CREB locus, was mapped to the proximal region of mouse chromosome 1.
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Affiliation(s)
- T J Cole
- Institute of Cell and Tumor Biology, German Cancer Research Center, Heidelberg
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19
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Buonavista N, Balzano C, Pontarotti P, Le Paslier D, Golstein P. Molecular linkage of the human CTLA4 and CD28 Ig-superfamily genes in yeast artificial chromosomes. Genomics 1992; 13:856-61. [PMID: 1322357 DOI: 10.1016/0888-7543(92)90169-s] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
CD28 and CTLA4 are structurally homologous single-V-domain molecules of the Ig superfamily, the genes of which comap on the same chromosomal bands in mouse and man. Using polymerase chain reactions, we isolated six yeast artificial chromosome (YAC) clones positive for CTLA4 and/or CD28 from a human-DNA-containing YAC library. Two double-positive clones, 365 and 550 kb long, respectively, were further studied. Detailed restriction enzyme maps showed that one of these YACs was nested in the other, that they both bore the same CD28- and CTLA4-hybridizing fragments, that similar fragments were seen in genomic DNA, and that the distance between the CD28 and CTLA4 genes was at most 150 kb and at least 25 kb. A CpG island was found between these genes. These results provide a high-resolution estimate of the physical distance between the CD28 and CTLA4 genes and constitute a basis for the isolation of neighboring structures.
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Affiliation(s)
- N Buonavista
- Centre d'immunologie INSERM-CNRS de Marseille-Luminy, France
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20
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Abstract
Application of quantitative methods to the study of leishmaniasis epidemiology has allowed Dye (1992) to pinpoint important biological parameters which, if they could be accurately measured in the field, would contribute most to our knowledge of the spread of disease and key targets for control. Three areas in which laboratory-based research could impact most on leishmaniasis epidemiology were highlighted by Dye (1992): (i) the development of accurate diagnostic tools which can distinguish between current and past infection; (ii) to determine the underlying molecular/genetic basis to virulence polymorphisms in the parasite and study these in the context of field epidemiological studies; and (iii) to provide the molecular tools to measure genetic variation in resistance to infection in humans and in reservoir hosts of disease. This paper describes current progress in attaining these goals, highlighting first the work on isolation and field application of genomic and kDNA probes for species-specific diagnosis, and the development of PCR-based assays which can be performed under field conditions. At a more preliminary stage, studies are described in which variability in the major molecular determinants of virulence (lipophosphoglycan, GP63, and members of the HSP70 family of stress proteins) identified through studies of laboratory models of infection, is being measured in primary field isolates of Leishmania peruviana. To complete the picture, current progress in identifying and cloning the genes which control host resistance to leishmanial infection is described, along with field studies of multicase families of human disease in which linkage analysis using marker genes from the chromosomal regions bearing these genes can be used to find evidence for their role in determining disease phenotypes in man. The projected view from these studies is that the future of leishmaniasis epidemiology will be all down to the DNA.
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Affiliation(s)
- J M Blackwell
- University of Cambridge Clinical School, Department of Medicine, Addenbrooke's Hospital
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21
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Diep A, Li C, Klisak I, Mohandas T, Sparkes RS, Gaynor R, Lusis AJ. Assignment of the gene for cyclic AMP-response element binding protein 2 (CREB2) to human chromosome 2q24.1-q32. Genomics 1991; 11:1161-3. [PMID: 1838349 DOI: 10.1016/0888-7543(91)90047-i] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The regulatory element TGACGTCA is found upstream of a number of viral and cellular genes. This element has been demonstrated to mediate cyclic AMP induction of cellular genes and activation of viral genes. A group of closely related cellular genes known as cyclic AMP-response element binding proteins (CREB) or activating transcription factor (ATF) have been found to bind to this motif and mediate activation by cyclic AMP and the adenovirus E1A protein. One of these genes, CREB1, was previously mapped to human chromosome 2q32.3-q34. Southern blot analysis of genomic DNA from a panel of mouse-human somatic cell hybrids indicated that the CREB2 gene, another member of this family, also resides on human chromosome 2. In situ hybridization further regionalized this gene to 2q24.1-q32. Thus, the genes for CREB1 and CREB2 that have only limited DNA sequence homology map to a similar region of the long arm of chromosome 2, though whether they are part of a gene cluster is unclear.
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Affiliation(s)
- A Diep
- Department of Medicine, University of California, Los Angeles 90024
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22
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Blackwell JM, Roach TI, Atkinson SE, Ajioka JW, Barton CH, Shaw MA. Genetic regulation of macrophage priming/activation: the Lsh gene story. Immunol Lett 1991; 30:241-8. [PMID: 1757110 DOI: 10.1016/0165-2478(91)90032-6] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This paper describes functional and genetic studies on the macrophage resistance gene Lsh/Ity/Bcg first described almost two decades ago. Working in vitro with resident peritoneal, liver (Kupffer cells) and bone marrow derived macrophages from congenic B10 (LshS) and B10.L-LshR mice it has been possible to demonstrate that the final effector mechanism for the gene in regulating antileishmanial activity involves production of reactive nitrogen rather than reactive oxygen intermediates. This in turn is dependent upon priming/activation of macrophages for enhanced TNF-alpha release which acts back on the macrophage in an autocrine manner to increase nitric oxide production. The precise point at which Lsh acts to control macrophage priming/activation has not been identified, but studies of early response gene expression show differences in KC mRNA levels at 2 h after LPS stimulation, and in c-fos mRNA as early as 20 min after stimulation with PMA plus ionophore, in peritoneal macrophages from congenic LshS and LshR mice. Data available suggest that both negative and positive signals may be involved in macrophage priming/activation, with LshS macrophages down-regulating their capacity for continued response to the autocrine loop. Work in progress will examine the role of TPA and cAMP response element-binding proteins in regulating gene expression in Lsh congenic mice. A major new initiative has also commenced to clone the Lsh gene by reverse genetics using yeast artificial chromosomes to walk towards Lsh from the closet proximal and distal markers on mouse chromosome 1.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J M Blackwell
- Department of Medical Parasitology, London School of Hygiene and Tropical Medicine, U.K
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23
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Ozawa K, Sudo T, Soeda E, Yoshida MC, Ishii S. Assignment of the human CREB2 (CRE-BP1) gene to 2q32. Genomics 1991; 10:1103-4. [PMID: 1833307 DOI: 10.1016/0888-7543(91)90210-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- K Ozawa
- Tsukuba Life Science Center, Institute of Physical and Chemical Research (RIKEN), Japan
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24
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Ehrenborg E, Vilhelmsdotter S, Bajalica S, Larsson C, Stern I, Koch J, Brøndum-Nielsen K, Luthman H. Structure and localization of the human insulin-like growth factor-binding protein 2 gene. Biochem Biophys Res Commun 1991; 176:1250-5. [PMID: 1710112 DOI: 10.1016/0006-291x(91)90420-c] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Insulin-like growth factor binding proteins (IGFBPs) are extracellular proteins that specifically bind IGF and modulate their effects. The human IGFBP2 gene was studied and shown to be localized to chromosome 2 region q33-q34, by somatic cell hybrid analysis and in situ hybridization. Structural characterization of the gene showed that it consists of four exons with three introns of lengths 27.0, 1.0, and 1.9 kilobase-pairs. Comparison of the encoded protein sequence of each exon in IGFBP1, 2, and 3 reveals the highest amino acid identity, 28%, in exon 1, while the lowest was found in exon 2. However, pairwise sequence comparisons demonstrate 50% identity between the protein sequences encoded by exon 4 in IGFBP1 and 2, while their respective identities with IGFBP3 are only 25 and 30%.
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Affiliation(s)
- E Ehrenborg
- Department of Clinical Genetics, Karolinska Institute, Stockholm, Sweden
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