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Li Z, Zhao B, Qin C, Wang Y, Li T, Wang W. Chromatin Dynamics in Digestive System Cancer: Commander and Regulator. Front Oncol 2022; 12:935877. [PMID: 35965507 PMCID: PMC9372441 DOI: 10.3389/fonc.2022.935877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 06/23/2022] [Indexed: 11/30/2022] Open
Abstract
Digestive system tumors have a poor prognosis due to complex anatomy, insidious onset, challenges in early diagnosis, and chemoresistance. Epidemiological statistics has verified that digestive system tumors rank first in tumor-related death. Although a great number of studies are devoted to the molecular biological mechanism, early diagnostic markers, and application of new targeted drugs in digestive system tumors, the therapeutic effect is still not satisfactory. Epigenomic alterations including histone modification and chromatin remodeling are present in human cancers and are now known to cooperate with genetic changes to drive the cancer phenotype. Chromatin is the carrier of genetic information and consists of DNA, histones, non-histone proteins, and a small amount of RNA. Chromatin and nucleosomes control the stability of the eukaryotic genome and regulate DNA processes such as transcription, replication, and repair. The dynamic structure of chromatin plays a key role in this regulatory function. Structural fluctuations expose internal DNA and thus provide access to the nuclear machinery. The dynamic changes are affected by various complexes and epigenetic modifications. Variation of chromatin dynamics produces early and superior regulation of the expression of related genes and downstream pathways, thereby controlling tumor development. Intervention at the chromatin level can change the process of cancer earlier and is a feasible option for future tumor diagnosis and treatment. In this review, we introduced chromatin dynamics including chromatin remodeling, histone modifications, and chromatin accessibility, and current research on chromatin regulation in digestive system tumors was also summarized.
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2
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Podocalyxin in Normal Tissue and Epithelial Cancer. Cancers (Basel) 2021; 13:cancers13122863. [PMID: 34201212 PMCID: PMC8227556 DOI: 10.3390/cancers13122863] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 05/31/2021] [Accepted: 06/02/2021] [Indexed: 12/13/2022] Open
Abstract
Podocalyxin (PODXL), a glycosylated cell surface sialomucin of the CD34 family, is normally expressed in kidney podocytes, vascular endothelial cells, hematopoietic progenitors, mesothelium, as well as a subset of neurons. In the kidney, PODXL functions primarily as an antiadhesive molecule in podocyte epithelial cells, regulating adhesion and cell morphology, and playing an essential role in the development and function of the organ. Outside the kidney, PODXL plays subtle roles in tissue remodelling and development. Furthermore, many cancers, especially those that originated from the epithelium, have been reported to overexpress PODXL. Collective evidence suggests that PODXL overexpression is linked to poor prognosis, more aggressive tumour progression, unfavourable treatment outcomes, and possibly chemoresistance. This review summarises our current knowledge of PODXL in normal tissue function and epithelial cancer, with a particular focus on its underlying roles in cancer metastasis, likely involvement in chemoresistance, and potential use as a diagnostic and prognostic biomarker.
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3
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The DNA methylation landscape in cancer. Essays Biochem 2020; 63:797-811. [PMID: 31845735 PMCID: PMC6923322 DOI: 10.1042/ebc20190037] [Citation(s) in RCA: 160] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 11/26/2019] [Accepted: 11/26/2019] [Indexed: 12/13/2022]
Abstract
As one of the most abundant and well-studied epigenetic modifications, DNA methylation plays an essential role in normal development and cellular biology. Global alterations to the DNA methylation landscape contribute to alterations in the transcriptome and deregulation of cellular pathways. Indeed, improved methods to study DNA methylation patterning and dynamics at base pair resolution and across individual DNA molecules on a genome-wide scale has highlighted the scope of change to the DNA methylation landscape in disease states, particularly during tumorigenesis. More recently has been the development of DNA hydroxymethylation profiling techniques, which allows differentiation between 5mC and 5hmC profiles and provides further insights into DNA methylation dynamics and remodeling in tumorigenesis. In this review, we describe the distribution of DNA methylation and DNA hydroxymethylation in different genomic contexts, first in normal cells, and how this is altered in cancer. Finally, we discuss DNA methylation profiling technologies and the most recent advances in single-cell methods, bisulfite-free approaches and ultra-long read sequencing techniques.
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4
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Tamayo-Orbegozo E, Amo L, Díez-García J, Amutio E, Riñón M, Alonso M, Arana P, Maruri N, Larrucea S. Emerging Role of Podocalyxin in the Progression of Mature B-Cell Non-Hodgkin Lymphoma. Cancers (Basel) 2020; 12:cancers12020396. [PMID: 32046309 PMCID: PMC7072361 DOI: 10.3390/cancers12020396] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 02/03/2020] [Accepted: 02/06/2020] [Indexed: 02/06/2023] Open
Abstract
Mature B-cell non-Hodgkin lymphoma (B-NHL) constitutes a group of heterogeneous malignant lymphoproliferative diseases ranging from indolent to highly aggressive forms. Although the survival after chemo-immunotherapy treatment of mature B-NHL has increased over the last years, many patients relapse or remain refractory due to drug resistance, presenting an unfavorable prognosis. Hence, there is an urgent need to identify new prognostic markers and therapeutic targets. Podocalyxin (PODXL), a sialomucin overexpressed in a variety of tumor cell types and associated with their aggressiveness, has been implicated in multiple aspects of cancer progression, although its participation in hematological malignancies remains unexplored. New evidence points to a role for PODXL in mature B-NHL cell proliferation, survival, migration, drug resistance, and metabolic reprogramming, as well as enhanced levels of PODXL in mature B-NHL. Here, we review the current knowledge on the contribution of PODXL to tumorigenesis, highlighting and discussing its role in mature B-NHL progression.
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Affiliation(s)
- Estíbaliz Tamayo-Orbegozo
- Regulation of the Immune System Group, Biocruces Bizkaia Health Research Institute, Plaza de Cruces 12, 48903 Barakaldo, Bizkaia, Spain; (E.T.-O.); (L.A.)
| | - Laura Amo
- Regulation of the Immune System Group, Biocruces Bizkaia Health Research Institute, Plaza de Cruces 12, 48903 Barakaldo, Bizkaia, Spain; (E.T.-O.); (L.A.)
| | - Javier Díez-García
- Microscopy Facility, Biocruces Bizkaia Health Research Institute, Plaza de Cruces 12, 48903 Barakaldo, Bizkaia, Spain;
| | - Elena Amutio
- Blood Cancer Group, Biocruces Bizkaia Health Research Institute, Hospital Universitario Cruces, Plaza de Cruces 12, 48903 Barakaldo, Bizkaia, Spain;
| | - Marta Riñón
- Regulation of the Immune System Group, Biocruces Bizkaia Health Research Institute, Hospital Universitario Cruces, Plaza de Cruces 12, 48903 Barakaldo, Bizkaia, Spain; (M.R.); (M.A.); (P.A.); (N.M.)
| | - Marta Alonso
- Regulation of the Immune System Group, Biocruces Bizkaia Health Research Institute, Hospital Universitario Cruces, Plaza de Cruces 12, 48903 Barakaldo, Bizkaia, Spain; (M.R.); (M.A.); (P.A.); (N.M.)
| | - Paula Arana
- Regulation of the Immune System Group, Biocruces Bizkaia Health Research Institute, Hospital Universitario Cruces, Plaza de Cruces 12, 48903 Barakaldo, Bizkaia, Spain; (M.R.); (M.A.); (P.A.); (N.M.)
| | - Natalia Maruri
- Regulation of the Immune System Group, Biocruces Bizkaia Health Research Institute, Hospital Universitario Cruces, Plaza de Cruces 12, 48903 Barakaldo, Bizkaia, Spain; (M.R.); (M.A.); (P.A.); (N.M.)
| | - Susana Larrucea
- Regulation of the Immune System Group, Biocruces Bizkaia Health Research Institute, Hospital Universitario Cruces, Plaza de Cruces 12, 48903 Barakaldo, Bizkaia, Spain; (M.R.); (M.A.); (P.A.); (N.M.)
- Correspondence:
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5
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Jiang Q, Lin D, Huang H, Wang G, Ye H. DNA Methylation Inhibits the Expression of CFSH in Mud Crab. Front Endocrinol (Lausanne) 2020; 11:163. [PMID: 32328029 PMCID: PMC7160318 DOI: 10.3389/fendo.2020.00163] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 03/09/2020] [Indexed: 11/13/2022] Open
Abstract
Crustacean female sex hormone (CFSH) is a key regulator of crustacean sex differentiation. The expression of Sp-CFSH in the mud crab Scylla paramamosain showed a tissue-specific and gender-variant pattern. To explore the role of DNA methylation in Sp-CFSH expression, the 5'-flanking region of Sp-CFSH was cloned, and one CpG island containing 12 CpG sites was found. Results of sodium bisulfite sequencing and methylated DNA immunoprecipitation showed that CpG island methylation was stable in the eyestalk ganglion during ovarian development of the females, which was significantly lower than that in the muscle of the females and in the eyestalk ganglion of the males. Such results suggested that the involvement of DNA methylation in regulating Sp-CFSH expression followed an eyestalk ganglion-specific and gender-variant pattern. The analysis of CpG dinucleotide site methylation and activity of the site-directed mutation (SDM) reporter vector further demonstrated that methylation inhibited Sp-CFSH expression by blocking the binding of transcription factor Sp1. The finding suggested for the first time the involvement of CpG methylation in the regulation of Sp-CFSH expression.
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Meneses-Morales I, Izquierdo-Torres E, Flores-Peredo L, Rodríguez G, Hernández-Oliveras A, Zarain-Herzberg Á. Epigenetic regulation of the human ATP2A3 gene promoter in gastric and colon cancer cell lines. Mol Carcinog 2019; 58:887-897. [PMID: 30657210 DOI: 10.1002/mc.22978] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 01/11/2019] [Accepted: 01/15/2019] [Indexed: 12/17/2023]
Abstract
The knowledge about the role of calcium-regulated pathways in cancer cell growth and differentiation could be useful for the development of new therapeutic approaches to diminish its mortality. The ATP2A genes encode for SERCA pumps, which modulate cytosolic Ca2+ concentration, regulating various cellular processes including cell growth. ATP2A3 gene transcriptional down-regulation has been reported in gastric and colon cancer, but there is still a lack of understanding about the epigenetic processes regulating its transcription. In this work, we report that butyrate, trichostatin A, and 5-azacytidine treatments increase SERCA3 expression, increased apoptosis, and decreased cell viability of the KATO-III gastric carcinoma cell line. We analyzed the methylation profile of the ATP2A3 gene promoter CpG island, finding clones with methylated status through -280 to -135 promoter region, harboring Sp1 and AP-2 binding sites, which could have a role in transcriptional repression. Post-translational modifications of histones show a major role in the ATP2A3 transcriptional regulation, and our results show histones marks linked to transcriptional repression associated with the -262 to -135 region, this repressive context changed to transcriptional permissive through SERCA3 re-expressing conditions. These results suggest that the nucleotide sequence from -280 to -135 position is an ATP2A3 epigenetic regulatory CpG region in KATO-III cells. Analyses of online-databases show a decreased SERCA3 expression in gastric and colon tumors, as well as overall survival results, showed that high SERCA3 expression could serve as a favorable prognostic marker for colon and gastric cancer patients.
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Affiliation(s)
- Iván Meneses-Morales
- Facultad de Medicina, Departamento de Bioquímica, Universidad Nacional Autónoma de México, Mexico City, México
| | - Eduardo Izquierdo-Torres
- Facultad de Medicina, Departamento de Bioquímica, Universidad Nacional Autónoma de México, Mexico City, México
| | - Lucía Flores-Peredo
- Facultad de Medicina, Departamento de Bioquímica, Universidad Nacional Autónoma de México, Mexico City, México
| | - Gabriela Rodríguez
- Facultad de Medicina, Departamento de Bioquímica, Universidad Nacional Autónoma de México, Mexico City, México
| | - Andrés Hernández-Oliveras
- Programa de Doctorado en Ciencias de la Salud, Universidad Veracruzana, Veracruz, México
- Instituto de Investigaciones Biológicas, Universidad Veracruzana, Xalapa, Veracruz, México
| | - Ángel Zarain-Herzberg
- Facultad de Medicina, Departamento de Bioquímica, Universidad Nacional Autónoma de México, Mexico City, México
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7
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Abstract
Cytosine methylation plays a major role in the regulation of sequential and tissue-specific expression of genes. De novo aberrant DNA methylation and demethylation are also crucial processes in tumorigenesis and tumor progression. The mechanisms of how and when such aberrant methylation and demethylation occur in tumor cells are still obscure, however. To evaluate subtle epigenetic alteration among minor subclonal populations, morphology-oriented epigenetic analysis is requisite, especially where heterogeneity and flexibility are as notable as in the process of cancer progression and cellular differentiation at critical stages. Therefore, establishment of reliable morphology-oriented epigenetic studies has become increasingly important in not only the experimental but also the diagnostic field. By selecting a subset of cells based on characteristic morphological features disclosed by microdissection or in situ hybridization, we discovered how methylation at certain CpG sites outside of CpG islands would play a crucial epigenetic role in the versatility and flexibility of gene expression during cancer progression. In this review, we first introduce technical aspects of two morphology-oriented epigenetic studies: (1) histoendonuclease-linked detection of methylated sites of DNA (HELMET), and (2) padlock probe and rolling circle amplification (RCA) for in situ identification of methylated cytosine in a sequence-dependent manner. We then present our observation of a novel MeCP2-mediated gene-silencing mechanism through the addition of methylation to a single-CpG-locus upstream of the TATA-box of the receptor activator of NF-κB ligand (RANKL) and of secreted frizzled-related protein 4 (SFRP4) gene promoters.
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Zhang Y, Wang H, Liu Y, Wang C, Wang J, Long C, Guo W, Sun X. Baicalein inhibits growth of Epstein-Barr virus-positive nasopharyngeal carcinoma by repressing the activity of EBNA1 Q-promoter. Biomed Pharmacother 2018; 102:1003-1014. [PMID: 29710517 DOI: 10.1016/j.biopha.2018.03.114] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 03/19/2018] [Accepted: 03/19/2018] [Indexed: 12/12/2022] Open
Abstract
Epstein-Barr virus (EBV) can establish a life-long latent infection in the host and is associated with various human malignancies, including nasopharyngeal carcinoma (NPC), the most common cancer originated from nasopharynx. EBV nuclear antigen 1 (EBNA1) is the only viral protein absolutely demanded for segregation, replication, transcription and maintenance of EBV viral genome in host cells. Baicalein, a bioactive flavonoid compound purified from the root of Scutellariae baicaleinsis, displays anti-inflammatory, immunosuppressive, and anti-tumor properties. In this study, the therapeutic effects and functional mechanism of baicalein on EBV-positive human NPC were determined. Cell Counting Kit-8 assays and cell formation colony were performed to investigate that baicalein can suppress proliferation of EBV-infected human NPC cells. Flow cytometric and hoechst 33258 staining results indicated that baicalein induced cell cycle arrest and apoptosis. Western blotting results demonstrated that baicalein down-regulates EBNA1 expression but not reduces the stability and half-life of EBNA1 in EBV-infected NPC cells. Additionally, the mRNA level of EBNA1 was examined by real time-PCR, the activity of EBNA1 Q promoter (Qp) was determined by dual luciferase reporter assay. Considering that transcription factor specificity protein 1 (Sp1) can maintain EBNA1 Qp active. Further analyses also elucidated that baicalein inhibits the expression of Sp1 while knock-down Sp1 by specific shRNAs decreases the expression and transcription levels of EBNA1. Therefore, the results suggested that baicalein may decrease EBNA1 expression level in EBV-positive NPC cells via inhibiting the activity of EBNA1 Q-promoter while over-expression of EBNA1 attenuate the inhibitory effect of baicalein. Finally, it was found that baicalein may strongly reduce growth of tumor in the mouse xenograft model of EBV-positive NPC. These results indicated that baicalein inhibits growth of EBV-positive NPC by repressing the activity of EBNA1 Q-promoter. Baicalein may be used as a therapeutic agent to treat EBV-positive NPC.
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Affiliation(s)
- Yaqian Zhang
- Stat Key Laboratory of Virology, Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, PR China
| | - Huan Wang
- Stat Key Laboratory of Virology, Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, PR China
| | - Yu Liu
- Stat Key Laboratory of Virology, Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, PR China
| | - Chao Wang
- Stat Key Laboratory of Virology, Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, PR China
| | - Jingchao Wang
- Stat Key Laboratory of Virology, Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, PR China
| | - Cong Long
- Stat Key Laboratory of Virology, Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, PR China
| | - Wei Guo
- Department of Pathology and Physiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, PR China
| | - Xiaoping Sun
- Stat Key Laboratory of Virology, Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, PR China; State Key Laboratory of Virology, Wuhan University, Wuhan, 430072, PR China.
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9
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Zheng M, Lin F, Hou F, Li G, Zhu C, Xu P, Xing C, Wang Q. Association between Promoter Methylation of Gene ERCC3 and Benzene Hematotoxicity. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2017; 14:ijerph14080921. [PMID: 28813025 PMCID: PMC5580623 DOI: 10.3390/ijerph14080921] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 07/21/2017] [Accepted: 07/24/2017] [Indexed: 12/12/2022]
Abstract
Benzene is a primary industrial chemical and a ubiquitous environmental pollutant. ERCC3 is a key player in nucleotide excision repair. Recent studies suggested that site-specific methylation is a possible mechanism of the transcriptional dysregulation by blocking transcription factors binding. We previously found that the average promoter methylation level of ERCC3 was increased in benzene-exposed workers. In order to test whether specific CpG sites of ERCC3 play an important role in benzene-induced epigenetic changes and whether the specific methylation patterns are associated with benzene hematotoxicity, we analyzed the promoter methylation levels of individual CpG sites, transcription factor binding motif and the correlation between aberrant CpG methylation and hematotoxicity in 76 benzene-exposed workers and 24 unexposed controls in China. Out of all the CpGs analyzed, two CpG units located 43 bp upstream and 99 bp downstream of the transcription start site of ERCC3 (CpG 2–4 and CpG 17–18, respectively), showed the most pronounced increase in methylation levels in benzene-exposed workers, compared with unexposed controls (Mean ± SD: 5.86 ± 2.77% vs. 4.92 ± 1.53%, p = 0.032; 8.45 ± 4.09% vs. 6.79 ± 2.50%, p = 0.024, respectively). Using the JASPAR CORE Database, we found that CpG 2–4 and CpG 17–18 were bound by three putative transcription factors (TFAP2A, E2F4 and MZF1). Furthermore, the methylation levels for CpG 2–4 were correlated negatively with the percentage of neutrophils (β = −0.676, p = 0.005) in benzene-exposed workers. This study demonstrates that CpG-specific DNA methylation in the ERCC3 promoter region may be involved in benzene-induced epigenetic modification and it may contribute to benzene-induced hematotoxicity.
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Affiliation(s)
- Min Zheng
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
| | - Feiliang Lin
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
- Key Laboratory of Genomic and Precision Medicine, Collaborative Innovation Center of Genetics and Development, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China.
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health, Sichuan University, Chengdu 610041, China.
| | - Fenxia Hou
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
| | - Guilan Li
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
| | - Caiying Zhu
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital and Center for Stem Cell Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300020, China.
| | - Peiyu Xu
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health, Sichuan University, Chengdu 610041, China.
| | - Caihong Xing
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
| | - Qianfei Wang
- Key Laboratory of Genomic and Precision Medicine, Collaborative Innovation Center of Genetics and Development, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China.
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10
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Zhang L, Zhang Q, Liu S, Chen Y, Li R, Lin T, Yu C, Zhang H, Huang Z, Zhao X, Tan X, Li Z, Ye Z, Ma J, Zhang B, Wang W, Shi W, Liang X. DNA methyltransferase 1 may be a therapy target for attenuating diabetic nephropathy and podocyte injury. Kidney Int 2017; 92:140-153. [PMID: 28318634 DOI: 10.1016/j.kint.2017.01.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 12/21/2016] [Accepted: 01/05/2017] [Indexed: 01/19/2023]
Affiliation(s)
- Li Zhang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | | | - Shuangxin Liu
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Yuanhan Chen
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Ruizhao Li
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Ting Lin
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Chunping Yu
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Hong Zhang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Zhongshun Huang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Xinchen Zhao
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; Southern Medical University, Guangzhou, China
| | - Xiaofan Tan
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Zhuo Li
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Zhiming Ye
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Jianchao Ma
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Bin Zhang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Wenjian Wang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Wei Shi
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.
| | - Xinling Liang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.
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Kang L, Yao C, Khodadadi-Jamayran A, Xu W, Zhang R, Banerjee NS, Chang CW, Chow LT, Townes T, Hu K. The Universal 3D3 Antibody of Human PODXL Is Pluripotent Cytotoxic, and Identifies a Residual Population After Extended Differentiation of Pluripotent Stem Cells. Stem Cells Dev 2016; 25:556-68. [PMID: 26886504 DOI: 10.1089/scd.2015.0321] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Podocalyxin-like protein (PODXL) is a member of CD34 family proteins. It is the protein that carries many post-translational epitopes responsible for various pluripotent surface markers including TRA-1-60, TRA-1-81, GCTM2, GP200, and mAb84. However, PODXL has not attracted the attention of stem cell biologists. Here, we report several features of PODXL mRNA and protein in pluripotent stem cells. Similar to the modification-dependent pluripotent epitopes, PODXL transcripts and carrier protein are also features of pluripotency. PODXL is highly expressed in early human embryos from oocytes up to four-cell stages. During reprogramming of human cells to pluripotency, in contrast to TRA-1-60 and TRA-1-81, PODXL is activated by KLF4 at a very early time of reprogramming. Although TRA-1-60 and TRA-1-81 are completely lost upon differentiation, a residual PODXL(+) population exists even after extended differentiation and they were identified by the universal human PODXL epitope 3D3. Unlike TRA-1-60 and TRA-1-81 epitopes that are unique to primate pluripotent stem cells (PSCs), PODXL carrier protein can be used as a murine surface marker. Most importantly, antibody to 3D3 epitope causes massive necrosis and apoptosis of human PSCs (hPSCs). We suggest that 3D3 antibody could be employed to eliminate the tumorigenic pluripotent cells in hPSC-derived cells for cell transplantation.
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Affiliation(s)
- Lei Kang
- 1 Stem Cell Institute, Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama.,2 Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama
| | - Chunping Yao
- 1 Stem Cell Institute, Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama.,2 Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama.,3 Department of Radiation Oncology, Shandong Cancer Hospital & Institute , Jinan, China
| | - Alireza Khodadadi-Jamayran
- 1 Stem Cell Institute, Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama.,2 Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama
| | - Weihua Xu
- 1 Stem Cell Institute, Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama.,2 Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama.,4 Longyan University , Fujian, China
| | - Ruowen Zhang
- 1 Stem Cell Institute, Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama.,2 Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama
| | - Nilam Sanjib Banerjee
- 2 Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama
| | - Chia-Wei Chang
- 1 Stem Cell Institute, Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama.,2 Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama
| | - Louise T Chow
- 2 Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama
| | - Tim Townes
- 1 Stem Cell Institute, Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama.,2 Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama
| | - Kejin Hu
- 1 Stem Cell Institute, Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama.,2 Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham , Birmingham, Alabama
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12
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Epigenetic modulations rendering cell-to-cell variability and phenotypic metastability. J Genet Genomics 2016; 43:503-11. [DOI: 10.1016/j.jgg.2016.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 05/12/2016] [Accepted: 05/25/2016] [Indexed: 02/01/2023]
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Spencer S, Gugliotta A, Koenitzer J, Hauser H, Wirth D. Stability of single copy transgene expression in CHOK1 cells is affected by histone modifications but not by DNA methylation. J Biotechnol 2015; 195:15-29. [DOI: 10.1016/j.jbiotec.2014.12.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Revised: 12/07/2014] [Accepted: 12/11/2014] [Indexed: 12/22/2022]
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14
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Lin CW, Sun MS, Wu HC. Podocalyxin-like 1 is associated with tumor aggressiveness and metastatic gene expression in human oral squamous cell carcinoma. Int J Oncol 2014; 45:710-8. [PMID: 24821609 DOI: 10.3892/ijo.2014.2427] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Accepted: 03/07/2014] [Indexed: 11/05/2022] Open
Abstract
Metastasis-mediated death remains a major challenge in cancer treatment due to the lack of identifiable biomarkers for early diagnosis. Identifying tumor-specific biomarkers is critical for the development of diagnostic and therapeutic tools. In the present study, we found that podocalyxin-like 1 (PODXL), a cell surface glycoprotein, was overexpressed in cancer tissues and was upregulated in lymph node metastatic tumor cells. The expression of PODXL was associated with the migratory ability of human oral squamous cell carcinoma (OSCC). Knockdown of PODXL by small hairpin RNA in the SAS OSCC cell line reduced tumor migration and invasion, and inhibited cell proliferation and colony formation. Suppression of PODXL resulted in downregulation of focal adhesion kinase (FAK) and paxillin phosphorylation. PODXL silencing inhibited filopodia formation, and suppressed F-actin and cortactin colocalization. In addition, PODXL expression was associated with the DNA methylation status, and treatment with the DNA methyltransferase inhibitor 5-aza-deoxycytidine increased the PODXL transcriptional level. Moreover, DNA microarray analysis data revealed that suppression of PODXL significantly affected subsets of genes associated with extracellular matrix organization, the epithelial-mesenchymal transition, and the expression of metastasis-related cytokines. Collectively, these data showed that the overexpression of PODXL may be associated with tumor aggressiveness and that PODXL could be a diagnostic biomarker for metastatic OSCC.
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Affiliation(s)
- Cheng-Wei Lin
- Department of Biochemistry, School of Medicine, Taipei Medical University, Taipei 115, Taiwan, R.O.C
| | - Min-Siou Sun
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 115, Taiwan, R.O.C
| | - Han-Chung Wu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 115, Taiwan, R.O.C
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15
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Jiang J, Liu Y, Fang W, Liu F. Sperm‑associated antigen 9 promotes astrocytoma cell invasion through the upregulation of podocalyxin. Mol Med Rep 2014; 10:417-22. [PMID: 24788963 DOI: 10.3892/mmr.2014.2168] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 03/18/2014] [Indexed: 01/29/2023] Open
Abstract
Podocalyxin (PODXL) has been found to increase the aggressive phenotype of a number of cancers, including astrocytoma. In addition, the progression of astrocytoma has been associated with sperm‑associated antigen 9 (SPAG9), a recently characterized oncoprotein. In the present study, the association between SPAG9 and PODXL in human astrocytoma invasion and the underlying mechanisms were investigated for the first time, to the best of our knowledge. Overexpression and knockdown of SPAG9 were performed in SW1783 (grade III astrocytoma) and U87 (grade IV astrocytoma; glioblastoma) cells, respectively. PODXL expression at both the mRNA and the protein level, as well as the PODXL gene promoter activity, were significantly increased and decreased in parallel with the overexpression and knockdown of SPAG9 in astrocytoma cells; these effects were blocked by the selective c‑Jun N‑terminal kinase (JNK) inhibitor SP600125 (5 µM) and restored by the JNK agonist anisomycin (25 ng/ml), respectively. SPAG9 overexpression significantly increased cell invasion and matrix metalloproteinase‑9 (MMP‑9) expression in SW1783 cells, and this effect was reversed by knockdown of PODXL. In U87 cells, knockdown of SPAG9 markedly decreased cell invasion and MMP‑9 expression, which was completely restored by overexpression of PODXL. In conclusion, it was demonstrated in the present study that SPAG9 upregulates PODXL expression in human astrocytoma cells at the PODXL gene promoter/transcriptional level through a JNK‑dependent mechanism and that PODXL is a critical mediator of the promoting effect of SPAG9 on astrocytoma cell invasion, possibly through upregulation of MMP‑9 expression. This study provides novel insights into the molecular mechanisms involved in astrocytoma invasion.
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Affiliation(s)
- Jiaode Jiang
- Department of Neurosurgery, The Third Xiangya Hospital, Hunan, P.R. China
| | - Yunsheng Liu
- Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan, P.R. China
| | - Wenhua Fang
- Department of Neurosurgery, The First Affiliated Hospital, Fujian Medical University, Fuzhou, Fujian, P.R. China
| | - Feng Liu
- Department of Neurosurgery, The Third Xiangya Hospital, Hunan, P.R. China
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16
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Malik RE, Rhodes SJ. The role of DNA methylation in regulation of the murine Lhx3 gene. Gene 2013; 534:272-81. [PMID: 24183897 DOI: 10.1016/j.gene.2013.10.045] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 10/09/2013] [Accepted: 10/23/2013] [Indexed: 12/20/2022]
Abstract
LHX3 is a LIM-homeodomain transcription factor with critical roles in pituitary and nervous system development. Mutations in the LHX3 gene are associated with pediatric diseases featuring severe hormone deficiencies, hearing loss, developmental delay, and other symptoms. The mechanisms that govern LHX3/Lhx3 transcription are poorly understood. In this study, we examined the role of DNA methylation in the expression status of the mouse Lhx3 gene. Pituitary cells that do not normally express Lhx3 (Pit-1/0 cells) were treated with 5-aza-2'-deoxycytidine, a demethylating reagent. This treatment leads to activation of Lhx3 gene expression suggesting that methylation contributes to Lhx3 regulation. Treatment of Pit-1/0 pituitary cells with a combination of a demethylating reagent and a histone deacetylase inhibitor led to rapid activation of Lhx3 expression, suggesting possible crosstalk between DNA methylation and histone modification processes. To assess DNA methylation levels, treated and untreated Pit-1/0 genomic DNAs were subjected to bisulfite conversion and sequencing. Treated Pit-1/0 cells had decreased methylation at specific sites in the Lhx3 locus compared to untreated cells. Chromatin immunoprecipitation assays demonstrated interactions between the MeCp2 methyl binding protein and Lhx3 promoter regions in the Pit-1/0 cell line. Overall, this study demonstrates that DNA methylation patterns of the Lhx3 gene are associated with its expression status.
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Affiliation(s)
- Raleigh E Malik
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Simon J Rhodes
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA; Department of Biology, Indiana University-Purdue University Indianapolis, IN, USA; Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN, USA.
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17
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Yu Z, Kong Q, Kone BC. Sp1 trans-activates and is required for maximal aldosterone induction of the αENaC gene in collecting duct cells. Am J Physiol Renal Physiol 2013; 305:F653-62. [PMID: 23804453 DOI: 10.1152/ajprenal.00177.2013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The epithelial Na+ channel (ENaC) in the distal nephron constitutes the rate-limiting step for renal sodium reabsorption. Aldosterone increases tubular sodium absorption in large part by increasing αENaC transcription in collecting duct principal cells. We previously reported that Af9 binds to +78/+92 of αENaC and recruits Dot1a to repress basal and aldosterone-sensitive αENaC transcription in mouse inner medullary collecting duct (mIMCD)3 cells. Despite this epigenetic repression, basal αENaC transcription is still evident and physiologically necessary, indicating basal operation of positive regulators. In the present study, we identified Sp1 as one such regulator. Gel shift and antibody competition assays using a +208/+240 probe revealed DNA-Sp1-containing complexes in mIMCD3 cells. Mutation of the +222/+229 element abrogated Sp1 binding in vitro and in promoter-reporter constructs stably expressed in mIMCD3 cells. Compared with the wild-type promoter, an αENaC promoter-luciferase construct with +222/+229 mutations exhibited much lower activity and impaired trans-activation in Sp1 overexpression experiments. Conversely, Sp1 knockdown inhibited endogenous αENaC mRNA and the activity of the wild-type αENaC promoter but not the mutated construct. Aldosterone triggered Sp1 recruitment to the αENaC promoter, which was required for maximal induction of αENaC promoter activity and was blocked by spironolactone. Sequential chromatin immunoprecipitation assays and functional tests of +78/+92 and +222/+229 αENaC promoter mutants indicated that while Sp1, Dot1a, and Af9 co-occupy the αENaC promoter, the Sp1 effects are functionally independent from Dot1a and Af9. In summary, Sp1 binding to a cis-element at +222/+229 represents the first identified constitutive driver of αENaC transcription, and it contributes to maximal aldosterone trans-activation of αENaC.
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Affiliation(s)
- Zhiyuan Yu
- Div. of Renal Diseases and Hypertension, The Univ. of Texas Medical School at Houston, 6431 Fannin, MSB 5.124, Houston, TX 77030, USA
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18
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Tsotakos NE, Sagnou M, Kotsopoulou ES, Tsilibary EC, Drossopoulou GI. Glucose-induced gradual phenotypic modulation of cultured human glomerular epithelial cells may be independent of Wilms' tumor 1 (WT1). BMC Cell Biol 2013; 14:28. [PMID: 23768159 PMCID: PMC3686613 DOI: 10.1186/1471-2121-14-28] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Accepted: 05/23/2013] [Indexed: 12/24/2022] Open
Abstract
Background Renal podocytes form the main filtration barrier possessing a unique phenotype maintained by proteins including podocalyxin and nephrin, the expression of which is suppressed in pathological conditions. We used an in vitro model of human glomerular epithelial cells (HGEC) to investigate the role of high glucose in dysregulating the podocytic epithelial phenotype and determined the time needed for this change to occur. Results In our in vitro podocyte system changes indicating podocyte dedifferentiation in the prolonged presence of high glucose included loss of podocalyxin, nephrin and CD10/CALLA concomitant with upregulation of mesenchymal vimentin. Our study demonstrates for the first time that podocyte-specific markers undergo changes of expression at different time intervals, since glucose-mediated podocalyxin downregulation is a progressive process that precedes downregulation of nephrin expression. Finally we demonstrate that high glucose permanently impaired WT1 binding to the podocalyxin gene promoter region but did not affect WT1 binding on the nephrin gene promoter region. Conclusion The presence of high glucose induced a phenotypic conversion of podocytes resembling partial dedifferentiation. Our study demonstrates that dysregulation of the normal podocytic phenotype is an event differentially affecting the expression of function-specific podocytic markers, exhibiting downregulation of the epithelial marker CD10/CALLA and PC first, followed by stably downregulated nephrin. Furthermore, it is herein suggested that WT1 may not be directly involved with upregulation of previously reduced PC and nephrin expression.
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Affiliation(s)
- Nikolaos E Tsotakos
- Institute of Biosciences and Applications, National Centre for Scientific Research Demokritos, Athens, Greece
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19
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Fang J, Wei H, Sun Y, Zhang X, Liu W, Chang Q, Wang R, Gong Y. Regulation of podocalyxin expression in the kidney of streptozotocin-induced diabetic rats with Chinese herbs (Yishen capsule). Altern Ther Health Med 2013; 13:76. [PMID: 23560927 PMCID: PMC3637235 DOI: 10.1186/1472-6882-13-76] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 03/27/2013] [Indexed: 11/23/2022]
Abstract
Background Diabetic nephropathy is an emergent issue in China with increase in patients with type II diabetes. There are several successful Chinese herbal products for the treatment of patients with diabetic nephropathy in China. However, the mechanisms mediating the biological activity of these products are still unclear. Podocalyxin is a sialoprotein critical to maintaining integrity of filtration function of glomerulus. Methods By employing streptozotocin-induced diabetic rats and a Chinese herb formulation (Yishen capsule), we examined the regulation of podocalyxin expression in the kidney by Yishen capsule through immunofluorescent staining and reverse transcriptase polymerase chain reaction. Results After injection of STZ, there were significant increase in both blood glucose and urinary protein. Serum creatinine and BUN were also increased in rats with injection of STZ. Moreover, expression of podocalyxin in the glomerulus was gradually reduced after injection of STZ. There was also a loss of podocyte foot processes in the glomerular basement membrane. However, Yishen capsule or benazepril was able to restore the expression of podocalyxin and podocyte foot processes in the kidney. Although Yishen capsule could reduce urinary protein level, it has little effect on blood glucose level in the rats injected with STZ. Conclusions Yishen capsule could attenuate the loss of podocalyxin in the glomerulus of rats injected with STZ.
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20
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Paonessa F, Latifi S, Scarongella H, Cesca F, Benfenati F. Specificity protein 1 (Sp1)-dependent activation of the synapsin I gene (SYN1) is modulated by RE1-silencing transcription factor (REST) and 5'-cytosine-phosphoguanine (CpG) methylation. J Biol Chem 2012; 288:3227-39. [PMID: 23250796 PMCID: PMC3561544 DOI: 10.1074/jbc.m112.399782] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The development and function of the nervous system are directly dependent on a well defined pattern of gene expression. Indeed, perturbation of transcriptional activity or epigenetic modifications of chromatin can dramatically influence neuronal phenotypes. The phosphoprotein synapsin I (Syn I) plays a crucial role during axonogenesis and synaptogenesis as well as in synaptic transmission and plasticity of mature neurons. Abnormalities in SYN1 gene expression have been linked to important neuropsychiatric disorders, such as epilepsy and autism. SYN1 gene transcription is suppressed in non-neural tissues by the RE1-silencing transcription factor (REST); however, the molecular mechanisms that allow the constitutive expression of this genetic region in neurons have not been clarified yet. Herein we demonstrate that a conserved region of human and mouse SYN1 promoters contains cis-sites for the transcriptional activator Sp1 in close proximity to REST binding motifs. Through a series of functional assays, we demonstrate a physical interaction of Sp1 on the SYN1 promoter and show that REST directly inhibits Sp1-mediated transcription, resulting in SYN1 down-regulation. Upon differentiation of neuroblastoma Neuro2a cells, we observe a decrease in endogenous REST and a higher stability of Sp1 on target GC boxes, resulting in an increase of SYN1 transcription. Moreover, methylation of Sp1 cis-sites in the SYN1 promoter region could provide an additional level of transcriptional regulation. Our results introduce Sp1 as a fundamental activator of basal SYN1 gene expression, whose activity is modulated by the neural master regulator REST and CpG methylation.
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Affiliation(s)
- Francesco Paonessa
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, via Morego 30, 16163 Genova, Italy
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21
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Zhao H, Liu LL, Du SH, Wang SQ, Zhang YP. Comparative analysis of the Shadoo gene between cattle and buffalo reveals significant differences. PLoS One 2012; 7:e46601. [PMID: 23071594 PMCID: PMC3468620 DOI: 10.1371/journal.pone.0046601] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 09/01/2012] [Indexed: 12/03/2022] Open
Abstract
Background While prions play a central role in the pathogenesis of transmissible spongiform encephalopathies, the biology of these proteins and the pathophysiology of these diseases remain largely unknown. Since no case of bovine spongiform encephalopathy (BSE) has ever been reported in buffalo despite their phylogenetic proximity to cattle, genetic differences may be driving the different susceptibilities of these two species to BSE. We thus hypothesized that differences in expression of the most recently identified member of the prion family or Shadoo (SPRN) gene may relate to these species-specific differences. Principal Findings We first analyzed and compared the polymorphisms of the SPRN gene (∼4.4 kb), including the putative promoter, coding and 3′ regions, and further verified the entire ORF and putative promoter. This yielded a total of 117 fixed differences, remarkably: 1) a 12-bp insertion/deletion polymorphism in the hydrophobic domain of the cattle but not buffalo gene, introducing a four amino acid expansion/contraction in a series of 5 tandem Ala/Gly-containing repeats; 2) two fixed missense mutations (102Ser→Gly and 119Thr→Ala), and three missense mutations (92Pro>Thr/Met, 122Thr>Ile and 139Arg>Trp) in the coding region presenting different (P<0.05) genotypic and allelic frequency distributions between cattle and buffalo; and, 3) functional luciferase-reporter experiments for the predicted promoter region, consistent with a significantly higher activity in buffalo than cattle. Supporting these findings, immunoblotting revealed higher relative expression levels of Sho protein in cerebrum from buffalo than from cattle. In addition, for cattle, highest Sho expression was detected in obex, as compared to cerebrum or cerebellum. Significance Our findings support Sho as a non-PrP specific marker for prion infections, with obex as the best tissue source for the detection of Sho in TSE rapid tests. Moreover, these discoveries may prove advantageous for further understanding the biology of prion diseases.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Binding Sites
- Brain/metabolism
- Buffaloes/genetics
- Cattle/genetics
- Encephalopathy, Bovine Spongiform/genetics
- Gene Components
- Gene Expression
- Gene Frequency
- Genes, Reporter
- INDEL Mutation
- Luciferases, Renilla/biosynthesis
- Luciferases, Renilla/genetics
- Mutation, Missense
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Organ Specificity
- Polymorphism, Genetic
- Protein Structure, Tertiary
- Repetitive Sequences, Nucleic Acid
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
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Affiliation(s)
- Hui Zhao
- Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming, People’s Republic of China
| | - Lin-Lin Liu
- Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming, People’s Republic of China
| | - Shou-Hui Du
- School of Life Science, Yunnan University, Kunming, People’s Republic of China
| | - Si-Qi Wang
- Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming, People’s Republic of China
| | - Ya-Ping Zhang
- Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming, People’s Republic of China
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, People’s Republic of China
- * E-mail:
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22
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Didych DA, Smirnov NA, Kotova ES, Akopov SB, Nikolaev LG, Sverdlov ED. Functional dissection of an enhancer-like element located within the second intron of the human U2AF1L4 gene. BIOCHEMISTRY (MOSCOW) 2011; 76:951-7. [PMID: 22022969 DOI: 10.1134/s0006297911080116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A detailed functional and evolutionary analysis of an enhancer element of the human genome (enhancer 12) located in the second intron of the U2AF1L4 gene, which we identified earlier, is presented. Overlapping fragments of the studied genome region were analyzed for enhancer activity, and the site responsible for the activity of this element was identified using transient transfections of HeLa cells. Comparison of the enhancer 12 sequence with orthologous sequences from seven primate species revealed the existence of evolutionarily conserved sequences within this element. One of the identified conservative regions is likely responsible for the enhancer activity and is able to specifically interact in vitro with proteins of HeLa cell nuclear extract. The ability of orthologous primate sequences to compete with enhancer 12 for binding with HeLa cell nuclear extract proteins and to enhance the activity of the reporter gene in transient transfection of HeLa cells is demonstrated.
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Affiliation(s)
- D A Didych
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia
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23
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Ristola M, Arpiainen S, Saleem MA, Holthöfer H, Lehtonen S. Transcription of nephrin-Neph3 gene pair is synergistically activated by WT1 and NF-κB and silenced by DNA methylation. Nephrol Dial Transplant 2011; 27:1737-45. [PMID: 21980157 DOI: 10.1093/ndt/gfr576] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Nephrin and Neph3 are homologous molecules expressed in the podocyte slit diaphragms that are essential for normal glomerular ultrafiltration. Nephrin and Neph3 genes form a bidirectional gene pair suggesting that they may share key features in their regulation. We investigated if nephrin and Neph3 genes have similar mechanisms in their transcriptional regulation focussing on transcription factor Wilms' tumour 1 (WT1) and nuclear factor-κB (NF-κB) and DNA methylation. METHODS Transcriptional regulation of nephrin and Neph3 by WT1 and NF-κB was analysed by overexpression studies, reporter gene assay and chromatin immunoprecipitation using A293 cells and cultured podocytes. The interaction between WT1 and NF-κB was studied by co-immunoprecipitation. The effect of NF-κB activator tumour necrosis factor-α (TNF-α) with or without NF-κB pathway inhibitor (BAY 11-7082) on nephrin and Neph3 messenger RNA (mRNA) expression and on cellular distribution of NF-κB was determined by quantitative polymerase chain reaction (PCR) and immunostaining, respectively. The role of DNA methylation in regulating nephrin and Neph3 genes was studied by demethylating agent (5-aza-2'-deoxycytidine) treatment and quantitative PCR. RESULTS WT1 and NF-κB interact with nephrin and Neph3 promoter and cooperatively regulate nephrin and Neph3. The cooperation was further supported by the physical interaction between WT1 and NF-κB. TNF-α increased nephrin and Neph3 mRNA expression and this effect was mediated by NF-κB. Furthermore, DNA methylation played a role in silencing nephrin and Neph3 expression in a cell-type and differentiation stage-dependent manner. CONCLUSION These results provide novel insights into the transcriptional regulation of nephrin and Neph3 genes and indicate that nephrin and Neph3 share the same mechanisms in their regulation.
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Affiliation(s)
- Mervi Ristola
- Department of Pathology, Haartman Institute, University of Helsinki, Helsinki, Finland
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24
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A 304 bp insertion/deletion mutation in promoter region induces the increase of porcine IDH3β gene expression. Mol Biol Rep 2011; 39:1419-26. [PMID: 21617947 DOI: 10.1007/s11033-011-0876-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2011] [Accepted: 05/14/2011] [Indexed: 10/18/2022]
Abstract
Obese and lean pig breeds show obvious differences in adipose metabolism/fat deposition; however, the molecular mechanism underlying phenotype variation remains unknown. In order to understand it, we analyzed the differences of gene expression in backfat between Meishan (a typical Chinese indigenous obese breed) and Large White (a lean Western breed) pigs. Here, we cloned porcine β subunit of IDH3 (IDH3B) and 2447 bp 5'-flanking sequence of this gene, and determined the genomic structure. Porcine IDH3B contains three isoforms, IDH3B ( 1 ), IDH3B ( 2 ) and IDH3B ( 3 ). Real-time RT-PCR revealed that these three isoforms were prevalently up-regulated in backfat of western commercial pigs, Large White, Landrace and Duroc, compared with Chinese indigenous breeds, Meishan and Tongcheng pigs. A 304 bp insertion/deletion variant was found in the 5'-flanking region. Dual-luciferase reporter assays showed that in vitro the promoter of IDH3B gene with the insertion had higher luciferase activity as compared with the wild type. Three genotypes AA, AB and BB, due to this insertion, were detected, and the frequency of allele A was dominant in western commercial pigs, whereas allele B predominated in Chinese indigenous breeds. IDH3B mRNA expression in Meishan pigs was more abundant with genotype AA than with genotype AB or BB, as in Large White pigs. In addition, the polymorphism was detected in 317 pigs of a Large White × Meishan F2 resource population. Association analysis showed that pigs with genotype AA possessed higher backfat thickness at buttocks than those with genotype AB (P < 0.05) or BB. These data suggested that the 304 bp insertion mutation in promoter region increased the expression of porcine IDH3β transcripts and this mutation might be a candidate marker for marker assistant selection in swine breeding.
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25
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Debret R, Cenizo V, Aimond G, André V, Devillers M, Rouvet I, Mégarbané A, Damour O, Sommer P. Epigenetic silencing of lysyl oxidase-like-1 through DNA hypermethylation in an autosomal recessive cutis laxa case. J Invest Dermatol 2010; 130:2594-601. [PMID: 20613779 DOI: 10.1038/jid.2010.186] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We have recently reported a case of cutis laxa caused by a fibulin-5 missense mutation (p.C217R). Skin fibroblasts from this individual showed an abnormal pattern of expression of several genes coding for elastic fiber-related proteins, including lysyl oxidase-like-1 (LOXL1). In this study we intended to elucidate the mechanism responsible for LOXL1 downregulation in these fibulin-5-mutant cells. We identified a proximal region (-442/-342) of the human LOXL1 promoter in which two binding sites for the transcription factor specific protein 1 (Sp-1) are required for gene activity in normal fibroblasts. Binding of Sp-1 to these sequences was dramatically reduced within cutis laxa cells, although Sp-1 expression was normal. Further analysis of the promoter sequence found increased methylation levels in cutis laxa cells compared with cells from unaffected individuals. When DNA methyltransferase activity was transiently inhibited in cutis laxa cells using the 5-aza-2'-deoxycytidine, we found a significant increase in LOXL1 expression. In conclusion, besides changes caused by the fibulin-5 mutation, LOXL1 gene regulation is affected by an epigenetic mechanism that can be reversed by an inhibitor of DNA methyltransferase activity. It is not yet known whether LOXL1 gene expression is affected in all cases of cutis laxa arising from fibulin-5 mutation.
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Affiliation(s)
- Romain Debret
- Institut de Biologie et Chimie des Protéines, Université Claude Bernard, Lyon, France.
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26
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Garrido-Martin EM, Blanco FJ, Fernandez-L A, Langa C, Vary CP, Lee UE, Friedman SL, Botella LM, Bernabeu C. Characterization of the human Activin-A receptor type II-like kinase 1 (ACVRL1) promoter and its regulation by Sp1. BMC Mol Biol 2010; 11:51. [PMID: 20587022 PMCID: PMC2906440 DOI: 10.1186/1471-2199-11-51] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2009] [Accepted: 06/29/2010] [Indexed: 11/28/2022] Open
Abstract
Background Activin receptor-like kinase 1 (ALK1) is a Transforming Growth Factor-β (TGF-β) receptor type I, mainly expressed in endothelial cells that plays a pivotal role in vascular remodelling and angiogenesis. Mutations in the ALK1 gene (ACVRL1) give rise to Hereditary Haemorrhagic Telangiectasia, a dominant autosomal vascular dysplasia caused by a haploinsufficiency mechanism. In spite of its patho-physiological relevance, little is known about the transcriptional regulation of ACVRL1. Here, we have studied the different origins of ACVRL1 transcription, we have analyzed in silico its 5'-proximal promoter sequence and we have characterized the role of Sp1 in the transcriptional regulation of ACVRL1. Results We have performed a 5'Rapid Amplification of cDNA Ends (5'RACE) of ACVRL1 transcripts, finding two new transcriptional origins, upstream of the one previously described, that give rise to a new exon undiscovered to date. The 5'-proximal promoter region of ACVRL1 (-1,035/+210) was analyzed in silico, finding that it lacks TATA/CAAT boxes, but contains a remarkably high number of GC-rich Sp1 consensus sites. In cells lacking Sp1, ACVRL1 promoter reporters did not present any significant transcriptional activity, whereas increasing concentrations of Sp1 triggered a dose-dependent stimulation of its transcription. Moreover, silencing Sp1 in HEK293T cells resulted in a marked decrease of ACVRL1 transcriptional activity. Chromatin immunoprecipitation assays demonstrated multiple Sp1 binding sites along the proximal promoter region of ACVRL1 in endothelial cells. Furthermore, demethylation of CpG islands, led to an increase in ACVRL1 transcription, whereas in vitro hypermethylation resulted in the abolishment of Sp1-dependent transcriptional activation of ACVRL1. Conclusions Our results describe two new transcriptional start sites in ACVRL1 gene, and indicate that Sp1 is a key regulator of ACVRL1 transcription, providing new insights into the molecular mechanisms that contribute to the expression of ACVRL1 gene. Moreover, our data show that the methylation status of CpG islands markedly modulates the Sp1 regulation of ACVRL1 gene transcriptional activity.
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Affiliation(s)
- Eva M Garrido-Martin
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Cientificas and Centro de Investigación Biomédica en Red de Enfermedades Raras, Ramiro de Maeztu 9, 28040 Madrid, Spain
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Lampo E, Duchateau L, Schepens B, Van Poucke M, Saelens X, Erkens T, Van Zeveren A, Peelman LJ. Identification of polymorphisms in the ovine Shadow of prion protein (SPRN) gene and assessment of their effect on promoter activity and susceptibility for classical scrapie. Anim Genet 2009; 41:169-78. [PMID: 19917049 DOI: 10.1111/j.1365-2052.2009.01984.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Shadow of prion protein (SPRN) is an interesting candidate gene thought to be involved in prion pathogenesis. In humans, an association has already been discovered between mutations in SPRN and the incidence of variant and sporadic Creutzfeldt-Jakob disease. However, in sheep, the effect of mutations in SPRN is largely unknown. Therefore, we analysed the presence of mutations in the entire ovine SPRN gene, their association with scrapie susceptibility and their effect on SPRN promoter activity. In total, 26 mutations were found: seven in the promoter region, four in intron 1, seven in the coding sequence and eight in the 3' untranslated region. The mutations detected in the coding sequence and the promoter region were subsequently analysed in more detail. In the coding sequence, a polymorphism causing a deletion of two alanines was found to be associated with susceptibility for classical scrapie in sheep. Furthermore, a functional analysis of deletion constructs of the ovine SPRN promoter revealed that the region 464 to 230 bp upstream of exon 1 (containing a putative AP-2 and putative Sp1 binding sites) is of functional importance for SPRN transcription. Six mutations in the SPRN promoter were also found to alter the promoter activity in vitro. However, no association between any of these promoter mutations and susceptibility for classical scrapie was found.
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Affiliation(s)
- E Lampo
- Department of Nutrition, Genetics and Ethology, Ghent University, Merelbeke, Belgium
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Drossopoulou GI, Tsotakos NE, Tsilibary EC. Impaired transcription factor interplay in addition to advanced glycation end products suppress podocalyxin expression in high glucose-treated human podocytes. Am J Physiol Renal Physiol 2009; 297:F594-603. [DOI: 10.1152/ajprenal.00203.2009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Podocalyxin represents a Wilms’ tumor suppressor protein (WT1)-regulated differentiation marker for glomerular epithelium. We provide evidence concerning mechanisms involved in the regulation of podocalyxin expression following long-term exposure to increased (25 mM) glucose levels. Prolonged culture of conditionally immortalized human podocytes in 25 mM glucose induced suppression of podocalyxin expression both at the protein and mRNA levels, whereas WT1 protein levels remained unaltered. WT1 interacted with another transcription factor, CRE-binding protein (CBP). This association was decreased by 40% in the presence of 25 mM glucose. Chromatin immunoprecipitation assays on chromatin from podocytes cultured in 25 mM glucose revealed reduced WT1 binding to podocalyxin promoter sequences, probably resulting from impaired WT1-CBP interactions. We explored the possible role of glucose-induced adducts (advanced glycation end products; AGEs) in impairing interactions between WT1 and CBP, with the use of aminoguanindine, an inhibitor of AGE formation. Podocytes were cultured in the simultaneous presence of 20 mM aminoguanidine and 25 mM glucose, and podocalyxin protein levels were examined. Aminoguanidine effectively prevented downregulation of podocalyxin protein levels but could not restore podocalyxin levels once expression was suppressed. Thus increased glucose apparently impaired the ability of WT1 to initiate transcription in part by decreased association of WT1 with CBP. Administration of aminoguanidine concomitant with increasing glucose levels in our in vitro model system protected from glucose-induced “silencing” of the podocalyxin gene, suggesting that AGEs play an important role in suppressing its expression in diabetic conditions.
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Ristola M, Arpiainen S, Saleem MA, Mathieson PW, Welsh GI, Lehtonen S, Holthöfer H. Regulation of Neph3 gene in podocytes--key roles of transcription factors NF-kappaB and Sp1. BMC Mol Biol 2009; 10:83. [PMID: 19703278 PMCID: PMC2736951 DOI: 10.1186/1471-2199-10-83] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Accepted: 08/24/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Neph3 (filtrin) is expressed in the glomerular podocytes where it localizes at the specialized cell adhesion structures of the foot processes called slit diaphragms which form the outermost layer of the glomerular filtration barrier. Neph3 protein shows homology and structural similarity to Neph1, Neph2 and nephrin, which all are crucial for maintaining the normal glomerular ultrafiltration function. The exact function of Neph3 in the kidney is not known but we have previously shown that the level of Neph3 mRNA is decreased in proteinuric diseases. This suggests that Neph3 may play a role in the pathogenesis of kidney damage, and emphasizes the need to analyze the regulatory mechanisms of Neph3 gene. In this study we investigated the transcriptional regulation of Neph3 gene by identifying transcription factors that control Neph3 expression. RESULTS We cloned and characterized approximately 5 kb fragment upstream of the Neph3 gene. Neph3 proximal promoter near the transcription start site was found to be devoid of TATA and CAAT boxes, but to contain a highly GC-rich area. Using promoter reporter gene constructs, we localized the main activating regulatory region of Neph3 gene in its proximal promoter region from -105 to -57. Within this region, putative transcription factor binding sites for NF-kappaB and Sp1 were found by computational analysis. Mutational screening indicated that NF-kappaB and Sp1 response elements are essential for the basal transcriptional activity of the Neph3 promoter. Co-transfection studies further showed that NF-kappaB and Sp1 regulate Neph3 promoter activity. In addition, overexpression of NF-kappaB increased endogenous Neph3 gene expression. Chromatin immunoprecipitation assay using cultured human podocytes demonstrated that both NF-kappaB and Sp1 interact with the Neph3 promoter. CONCLUSION Our results show that NF-kappaB and Sp1 are key regulators of Neph3 expression at the basal level in podocytes, therefore providing new insight into the molecular mechanisms that contribute to the expression of Neph3 gene.
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Affiliation(s)
- Mervi Ristola
- Department of Bacteriology and Immunology, Haartman Institute, P,O, Box 21, 00014 University of Helsinki, Finland.
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Brunner AL, Johnson DS, Kim SW, Valouev A, Reddy TE, Neff NF, Anton E, Medina C, Nguyen L, Chiao E, Oyolu CB, Schroth GP, Absher DM, Baker JC, Myers RM. Distinct DNA methylation patterns characterize differentiated human embryonic stem cells and developing human fetal liver. Genome Res 2009; 19:1044-56. [PMID: 19273619 DOI: 10.1101/gr.088773.108] [Citation(s) in RCA: 214] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
To investigate the role of DNA methylation during human development, we developed Methyl-seq, a method that assays DNA methylation at more than 90,000 regions throughout the genome. Performing Methyl-seq on human embryonic stem cells (hESCs), their derivatives, and human tissues allowed us to identify several trends during hESC and in vivo liver differentiation. First, differentiation results in DNA methylation changes at a minimal number of assayed regions, both in vitro and in vivo (2%-11%). Second, in vitro hESC differentiation is characterized by both de novo methylation and demethylation, whereas in vivo fetal liver development is characterized predominantly by demethylation. Third, hESC differentiation is uniquely characterized by methylation changes specifically at H3K27me3-occupied regions, bivalent domains, and low density CpG promoters (LCPs), suggesting that these regions are more likely to be involved in transcriptional regulation during hESC differentiation. Although both H3K27me3-occupied domains and LCPs are also regions of high variability in DNA methylation state during human liver development, these regions become highly unmethylated, which is a distinct trend from that observed in hESCs. Taken together, our results indicate that hESC differentiation has a unique DNA methylation signature that may not be indicative of in vivo differentiation.
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Affiliation(s)
- Alayne L Brunner
- Department of Genetics, Stanford University School of Medicine, Stanford, California 94305, USA
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Green LM, Wagner KJ, Campbell HA, Addison K, Roberts SGE. Dynamic interaction between WT1 and BASP1 in transcriptional regulation during differentiation. Nucleic Acids Res 2008; 37:431-40. [PMID: 19050011 PMCID: PMC2632906 DOI: 10.1093/nar/gkn955] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The Wilms' tumour suppressor protein WT1 plays a central role in the development of the kidney and also other organs. WT1 can act as a transcription factor with highly context-specific activator and repressor functions. We previously identified Brain Acid Soluble Protein 1 (BASP1) as a transcriptional cosuppressor that can block the transcriptional activation function of WT1. WT1 and BASP1 are co-expressed during nephrogenesis and both proteins ultimately become restricted to the podocyte cells of the adult kidney. Here, we have analysed the WT1/BASP1 complex in a podocyte precursor cell line that can be induced to differentiate. Chromatin immunoprecipitation revealed that WT1 and BASP1 occupy the promoters of the Bak, c-myc and podocalyxin genes in podocyte precursor cells. During differentiation-dependent upregulation of podocalyxin expression BASP1 occupancy of the podocalyxin promoter is reduced compared to that of WT1. In contrast, the repressive WT1/BASP1 occupancy of the c-myc and Bak promoters is maintained and these genes are downregulated during the differentiation process. We provide evidence that the regulation of BASP1 promoter occupancy involves the sumoylation of BASP1. Our results reveal a dynamic cooperation between WT1 and BASP1 in the regulation of gene expression during differentiation.
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Affiliation(s)
- Laura M Green
- Faculty of Life Sciences, The Michael Smith Building University of Manchester Oxford Road, Manchester M13 9PT, UK
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Ren ZQ, Wang Y, Xu YJ, Wang LJ, Lei MG, Zuo B, Li FE, Xu DQ, Zheng R, Deng CY, Jiang SW, XIONG YZ. Identification of a differentially expressed gene, ACL, between Meishan × Large White and Large White × Meishan F1 hybrids and their parents. Genet Sel Evol 2008. [DOI: 10.1051/gse:2008024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Koch LK, Zhou H, Ellinger J, Biermann K, Höller T, von Rücker A, Büttner R, Gütgemann I. Stem cell marker expression in small cell lung carcinoma and developing lung tissue. Hum Pathol 2008; 39:1597-605. [PMID: 18656241 DOI: 10.1016/j.humpath.2008.03.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2007] [Revised: 02/01/2008] [Accepted: 03/01/2008] [Indexed: 01/10/2023]
Abstract
Histopathologic and clinical findings suggest that small cell lung cancer is derived from a multipotent proximal airway epithelial cell. In order to investigate the histogenetic origin of small cell lung cancer, we compared stem cell marker expression in human fetal lung tissue, human adult bronchial tissue, and a cohort of 64 small cell lung cancers. Supporting derivation of a multipotent precursor cell, 87.5% (56/64) of small cell lung cancers showed a dot-like expression of podocalyxin-like protein 1 (PODXL-1), a marker of embryonic and hematopoetic stem cells. Of small cell lung cancers, 98.4% (63/64) ubiquitously expressed Bmi-1, a key player in self-renewal of stem cells. Oct4 and AP2gamma were not expressed. Although podocalyxin-like protein 1 did not correlate with p53 or Wilms tumor suppressor 1, known regulators of podocalyxin-like protein 1, we could demonstrate demethylated CpG islands in the podocalyxin-like protein 1 promoter in small cell lung cancer, indicating epigenetic regulation. During fetal lung development and within adult bronchial mucosa, Bmi-1 was expressed ubiquitously. In contrast, podocalyxin-like protein 1 was detected in few stromal cells during the pseudoglandular phase (n = 7) and, importantly, in clustered epithelial cells within proximal bronchi and the trachea during the canalicular phase (n = 10). Interestingly, podocalyxin-like protein 1 was not expressed in normal or metaplastic adult bronchial epithelium (n = 36) but was expressed in sparse epithelial cells in half of the cases of normal tumor adjacent bronchial mucosa (20/40). Taken together, we show that small cell lung cancers and clustered epithelial cells in developing proximal bronchi share the expression of stem cell markers, suggesting a possible histogenetic link.
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Rodríguez RB, Butta N, Larrucea S, Alonso S, Parrilla R. Production and characterization of murine monoclonal antibodies against human podocalyxin. ACTA ACUST UNITED AC 2007; 68:407-17. [PMID: 17092254 DOI: 10.1111/j.1399-0039.2006.00692.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Podocalyxin (podxl) is a protein with a peptide bone of approximately 55.5 kDa that undergoes a post-translational glycosylation, yielding a final molecular mass from approximately 145 to approximately 200 kDa. This protein is normally found covering the vascular side of the epithelial glomerular cells, the podocytes, and its presence is essential to maintain a normal renal function. It has also been reported in other cells and tissues although its function has not been yet clarified. The carboxy-terminal intracellular domain of podxl is nearly 100% identical in most species; however, the ectodomain shows considerable variations although the cysteine residues are conserved. Detection of this protein is elusive, most likely due to differences in post-translational modifications. We aimed at producing murine monoclonal antibodies against human podxl. Immunization with Chinese hamster ovarian -hpodxl-green fluorescence protein live cells yielded five different monoclonal antibodies that were characterized by enzyme-linked immunosorbent assay, sodium dodecyl sulfate-polyacrylamide gel electrophoresis/western blot, flow cytometry, immunohistochemistry, and immunoprecipitation. The different behavior of these antibodies suggests that some of them may react against epitopes masked by different glycosylated protein moieties.
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Affiliation(s)
- R B Rodríguez
- Department of Physiopathology and Human Molecular Genetics, Centro de Investigaciones Biológicas (CSIC), 28040-Madrid, Spain
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Schopperle WM, DeWolf WC. The TRA-1-60 and TRA-1-81 human pluripotent stem cell markers are expressed on podocalyxin in embryonal carcinoma. Stem Cells 2006; 25:723-30. [PMID: 17124010 DOI: 10.1634/stemcells.2005-0597] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We have previously identified the cell adhesion protein podocalyxin expressed in a human pluripotent stem cell, embryonal carcinoma (EC), which is a malignant germ cell. Podocalyxin is a heavily glycosylated membrane protein with amino acid sequence homology to the hematopoietic stem cell marker CD34. Since the initial discovery of podocalyxin in a cancerous stem cell, numerous new studies have identified podocalyxin in many different human cancers and in embryonic stem cells lines (ES) derived from human embryos. Embryonal carcinoma, as do all human pluripotent stem cells, expresses TRA-1-60 and TRA-1-81 antigens, and although their molecular identities are unknown, they are commonly used as markers of undifferentiated pluripotent human stem cells. We report here that purified podocalyxin from embryonal carcinoma has binding activity with the TRA-1-60 and TRA-1-81 antibodies. Embryonal carcinoma cells treated with retinoic acid undergo differentiation and lose the TRA-1-60/TRA-1-81 markers from their plasma membrane surface. We show that podocalyxin is modified in the retinoic acid-treated cells and has an apparent molecular mass of 170 kDa on protein blots as compared with the apparent 200-kDa molecular weight form of podocalyxin expressed in untreated cells. Furthermore, the modified form of podocalyxin no longer reacts with the TRA-1-60/TRA-1-81 antibodies. Thus, embryonal carcinoma expresses two distinct forms of podocalyxin, and the larger version is a molecular carrier of the human stem cell-defining antigens TRA-1-60 and TRA-1-81.
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Affiliation(s)
- William M Schopperle
- Department of Surgery, Beth Israel Deaconess Medical Center, RW-875, 330 Brookline Ave., Boston, MA 02215, USA.
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