1
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Grancharova T, Gerbin KA, Rosenberg AB, Roco CM, Arakaki JE, DeLizo CM, Dinh SQ, Donovan-Maiye RM, Hirano M, Nelson AM, Tang J, Theriot JA, Yan C, Menon V, Palecek SP, Seelig G, Gunawardane RN. A comprehensive analysis of gene expression changes in a high replicate and open-source dataset of differentiating hiPSC-derived cardiomyocytes. Sci Rep 2021; 11:15845. [PMID: 34349150 PMCID: PMC8338992 DOI: 10.1038/s41598-021-94732-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 07/12/2021] [Indexed: 12/13/2022] Open
Abstract
We performed a comprehensive analysis of the transcriptional changes occurring during human induced pluripotent stem cell (hiPSC) differentiation to cardiomyocytes. Using single cell RNA-seq, we sequenced > 20,000 single cells from 55 independent samples representing two differentiation protocols and multiple hiPSC lines. Samples included experimental replicates ranging from undifferentiated hiPSCs to mixed populations of cells at D90 post-differentiation. Differentiated cell populations clustered by time point, with differential expression analysis revealing markers of cardiomyocyte differentiation and maturation changing from D12 to D90. We next performed a complementary cluster-independent sparse regression analysis to identify and rank genes that best assigned cells to differentiation time points. The two highest ranked genes between D12 and D24 (MYH7 and MYH6) resulted in an accuracy of 0.84, and the three highest ranked genes between D24 and D90 (A2M, H19, IGF2) resulted in an accuracy of 0.94, revealing that low dimensional gene features can identify differentiation or maturation stages in differentiating cardiomyocytes. Expression levels of select genes were validated using RNA FISH. Finally, we interrogated differences in cardiac gene expression resulting from two differentiation protocols, experimental replicates, and three hiPSC lines in the WTC-11 background to identify sources of variation across these experimental variables.
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Affiliation(s)
| | | | - Alexander B Rosenberg
- Department of Electrical & Computer Engineering, University of Washington, Seattle, WA, USA.,, Parse Biosciences, Seattle, WA, USA
| | - Charles M Roco
- , Parse Biosciences, Seattle, WA, USA.,Department of Bioengineering, University of Washington, Seattle, WA, USA
| | | | | | | | | | - Matthew Hirano
- Department of Electrical & Computer Engineering, University of Washington, Seattle, WA, USA
| | | | - Joyce Tang
- Allen Institute for Cell Science, Seattle, WA, USA
| | - Julie A Theriot
- Allen Institute for Cell Science, Seattle, WA, USA.,Department of Biology, Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
| | - Calysta Yan
- Allen Institute for Cell Science, Seattle, WA, USA
| | - Vilas Menon
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
| | - Sean P Palecek
- Department of Chemical and Biological Engineering, University of Wisconsin - Madison, Madison, WI, USA
| | - Georg Seelig
- Department of Electrical & Computer Engineering, University of Washington, Seattle, WA, USA.,Paul G. Allen School of Computer Science and Engineering, University of Washington, Seattle, WA, USA
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2
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Nadella KS, Berthon A, Almeida MQ, Levy I, Faucz FR, Stratakis CA. Insulin-like growth factor 2 (IGF2) expression in adrenocortical disease due to PRKAR1A mutations compared to other benign adrenal tumors. Endocrine 2021; 72:823-834. [PMID: 33420948 DOI: 10.1007/s12020-020-02583-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 12/01/2020] [Indexed: 01/19/2023]
Abstract
PURPOSE Insulin-like growth factor-II (IGF2), a key regulator of cell growth and development, is tightly regulated in its expression by epigenetic control that maintains its monoallelic expression in most tissues. Biallelic expression of IGF2 resulting from loss of imprinting (LOI) has been reported in adrenocortical tumors. In this study, we wanted to check whether adrenocortical lesions due to PRKAR1A mutations lead to increased IGF2 expression from LOI and compare these findings to those in other benign adrenal lesions. METHODS We compared the expression of IGF2 by RNA and protein studies in primary pigmented nodular adrenocortical disease (PPNAD) caused by PRKAR1A gene mutations to that in primary macronodular adrenocortical hyperplasia (PMAH) and cortisol-producing adenomas (CPA) that did not have any mutations in known genes. We also checked LOI in all lesions by DNA allelic studies and the expression of other components of IGF2 signaling at the RNA and protein level. RESULTS We identified cell clusters overexpressing IGF2 in PPNAD; although immunostaining was patchy, overall, by RNA and immunoblotting PPNAD expressed high IGF2 message and protein. However, this was not due to LOI, as there was no correlation between IGF2 expression and the presence of LOI. CONCLUSIONS Our data pointed to over-expression of IGF2 protein in PPNAD compared to other benign adrenocortical lesions, such as PMAH and CPA. However, there was no correlation of IGF2 mRNA levels with LOI of IGF2/H19. The discrepancy between mRNA and protein levels with regards to LOI points, perhaps, to different control of IGF2 gene expression in PPNAD.
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Affiliation(s)
- Kiran S Nadella
- Section on Genetics & Endocrinology (SEGEN), Intramural Research Program (IRP), Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD), Bethesda, MD, USA
| | - Annabel Berthon
- Section on Genetics & Endocrinology (SEGEN), Intramural Research Program (IRP), Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD), Bethesda, MD, USA
| | - Madson Q Almeida
- Section on Genetics & Endocrinology (SEGEN), Intramural Research Program (IRP), Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD), Bethesda, MD, USA
| | - Isaac Levy
- Section on Genetics & Endocrinology (SEGEN), Intramural Research Program (IRP), Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD), Bethesda, MD, USA
| | - Fabio R Faucz
- Section on Genetics & Endocrinology (SEGEN), Intramural Research Program (IRP), Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD), Bethesda, MD, USA.
| | - Constantine A Stratakis
- Section on Genetics & Endocrinology (SEGEN), Intramural Research Program (IRP), Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD), Bethesda, MD, USA
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3
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Juhlin CC, Bertherat J, Giordano TJ, Hammer GD, Sasano H, Mete O. What Did We Learn from the Molecular Biology of Adrenal Cortical Neoplasia? From Histopathology to Translational Genomics. Endocr Pathol 2021; 32:102-133. [PMID: 33534120 DOI: 10.1007/s12022-021-09667-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/12/2021] [Indexed: 12/23/2022]
Abstract
Approximately one-tenth of the general population exhibit adrenal cortical nodules, and the incidence has increased. Afflicted patients display a multifaceted symptomatology-sometimes with rather spectacular features. Given the general infrequency as well as the specific clinical, histological, and molecular considerations characterizing these lesions, adrenal cortical tumors should be investigated by endocrine pathologists in high-volume tertiary centers. Even so, to distinguish specific forms of benign adrenal cortical lesions as well as to pinpoint malignant cases with the highest risk of poor outcome is often challenging using conventional histology alone, and molecular genetics and translational biomarkers are therefore gaining increased attention as a possible discriminator in this context. In general, our understanding of adrenal cortical tumorigenesis has increased tremendously the last decade, not least due to the development of next-generation sequencing techniques. Comprehensive analyses have helped establish the link between benign aldosterone-producing adrenal cortical proliferations and ion channel mutations, as well as mutations in the protein kinase A (PKA) signaling pathway coupled to cortisol-producing adrenal cortical lesions. Moreover, molecular classifications of adrenal cortical tumors have facilitated the distinction of benign from malignant forms, as well as the prognostication of the individual patients with verified adrenal cortical carcinoma, enabling high-resolution diagnostics that is not entirely possible by histology alone. Therefore, combinations of histology, immunohistochemistry, and next-generation multi-omic analyses are all needed in an integrated fashion to properly distinguish malignancy in some cases. Despite significant progress made in the field, current clinical and pathological challenges include the preoperative distinction of non-metastatic low-grade adrenal cortical carcinoma confined to the adrenal gland, adoption of individualized therapeutic algorithms aligned with molecular and histopathologic risk stratification tools, and histological confirmation of functional adrenal cortical disease in the context of multifocal adrenal cortical proliferations. We herein review the histological, genetic, and epigenetic landscapes of benign and malignant adrenal cortical neoplasia from a modern surgical endocrine pathology perspective and highlight key mechanisms of value for diagnostic and prognostic purposes.
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Affiliation(s)
- C Christofer Juhlin
- Department of Oncology-Pathology, Karolinska Institutet, Stockholm, Sweden
- Department of Pathology and Cytology, Karolinska University Hospital, Stockholm, Sweden
| | - Jérôme Bertherat
- Université de Paris, Institut Cochin, Inserm U1016, CNRS UMR8104, 75014, Paris, France
- Department of Endocrinology and National Reference Center for Rare Adrenal Disorders, Hôpital Cochin, Assistance Publique Hôpitaux de Paris, 75014, Paris, France
| | - Thomas J Giordano
- Department of Pathology and Internal Medicine, University of Michigan, MI, Ann Arbor, USA
| | - Gary D Hammer
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Hironobu Sasano
- Department of Pathology, Tohoku University School of Medicine, Sendai, Japan
| | - Ozgur Mete
- Department of Pathology, University Health Network, Toronto, ON, Canada.
- Endocrine Oncology Site, Princess Margaret Cancer Centre, Toronto, ON, Canada.
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.
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4
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Xu F, Liu J, Na L, Chen L. Roles of Epigenetic Modifications in the Differentiation and Function of Pancreatic β-Cells. Front Cell Dev Biol 2020; 8:748. [PMID: 32984307 PMCID: PMC7484512 DOI: 10.3389/fcell.2020.00748] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 07/17/2020] [Indexed: 12/14/2022] Open
Abstract
Diabetes, a metabolic disease with multiple causes characterized by high blood sugar, has become a public health problem. Hyperglycaemia is caused by deficiencies in insulin secretion, impairment of insulin function, or both. The insulin secreted by pancreatic β cells is the only hormone in the body that lowers blood glucose levels and plays vital roles in maintaining glucose homeostasis. Therefore, investigation of the molecular mechanisms of pancreatic β cell differentiation and function is necessary to elucidate the processes involved in the onset of diabetes. Although numerous studies have shown that transcriptional regulation is essential for the differentiation and function of pancreatic β cells, increasing evidence indicates that epigenetic mechanisms participate in controlling the fate and regulation of these cells. Epigenetics involves heritable alterations in gene expression caused by DNA methylation, histone modification and non-coding RNA activity that does not result in DNA nucleotide sequence alterations. Recent research has revealed that a variety of epigenetic modifications play an important role in the development of diabetes. Here, we review the mechanisms by which epigenetic regulation affects β cell differentiation and function.
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Affiliation(s)
- Fei Xu
- Department of Microbiology and Immunology, Shanghai University of Medicine & Health Sciences, Shanghai, China.,Collaborative Innovation Center of Shanghai University of Medicine & Health Sciences, Shanghai, China
| | - Jing Liu
- Department of Inspection and Quarantine, Shanghai University of Medicine & Health Sciences, Shanghai, China
| | - Lixin Na
- Collaborative Innovation Center of Shanghai University of Medicine & Health Sciences, Shanghai, China.,Department of Inspection and Quarantine, Shanghai University of Medicine & Health Sciences, Shanghai, China
| | - Linjun Chen
- Department of Inspection and Quarantine, Shanghai University of Medicine & Health Sciences, Shanghai, China
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5
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Linnér A, Almgren M. Epigenetic programming-The important first 1000 days. Acta Paediatr 2020; 109:443-452. [PMID: 31603247 DOI: 10.1111/apa.15050] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 09/07/2019] [Accepted: 10/08/2019] [Indexed: 12/13/2022]
Abstract
The perinatal period is a time of fast physiological change, including epigenetic programming. Adverse events may lead to epigenetic changes, with implications for health and disease. Our review covers the basics of clinical epigenetics and explores the latest research, including the role of epigenetic processes in complex disease phenotypes, such as neurodevelopmental, neurodegenerative and immunological disorders. Some studies suggest that epigenetic alterations are linked to early life environmental stressors, including mode of delivery, famine, psychosocial stress, severe institutional deprivation and childhood abuse. CONCLUSION: Epigenetic modifications due to perinatal environmental exposures can lead to lifelong, but potentially reversible, phenotypic alterations and disease.
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Affiliation(s)
- Agnes Linnér
- Department of Women’s and Children’s Health Karolinska Institutet Stockholm Sweden
| | - Malin Almgren
- Department of Clinical Neuroscience Karolinska Institutet Stockholm Sweden
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6
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Blood transcriptome analysis in a buck-ewe hybrid and its parents. Sci Rep 2019; 9:17492. [PMID: 31767945 PMCID: PMC6877586 DOI: 10.1038/s41598-019-53901-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 11/07/2019] [Indexed: 11/24/2022] Open
Abstract
Examples of living sheep-goat hybrids are rare, mainly due to incorrect chromosome pairing, which is thought to be the main cause for species incompatibility. This case represents the first report of a buck-ewe hybrid and the first mammalian hybrid to be analyzed with next generation sequencing. The buck-ewe hybrid had an intermediate karyotype to the parental species, with 57 chromosomes. Analysis of the blood transcriptomes of the hybrid and both parents revealed that gene expression levels differed between the hybrid and its parents. This could be explained in part by age-dependent differences in gene expression. Contribution to the geep transcriptome was larger from the paternal, compared to the maternal, genome. Furthermore, imprinting patterns deviated considerably from what is known from other mammals. Potentially deleterious variants appeared to be compensated for by monoallelic expression of transcripts. Hence, the data imply that the buck-ewe hybrid compensated for the phylogenetic distance between the parental species by several mechanisms: adjustment of gene expression levels, adaptation to imprinting incompatibilities, and selective monoallelic expression of advantageous transcripts. This study offers a unique opportunity to gain insights into the transcriptome biology and regulation of a hybrid mammal.
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7
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Luo X, Deng C, Liu F, Liu X, Lin T, He D, Wei G. HnRNPL promotes Wilms tumor progression by regulating the p53 and Bcl2 pathways. Onco Targets Ther 2019; 12:4269-4279. [PMID: 31213844 PMCID: PMC6549776 DOI: 10.2147/ott.s203046] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 04/16/2019] [Indexed: 12/17/2022] Open
Abstract
Background: Wilms tumor (WT) is the most common renal tumor in children with diffusely anaplastic or unfavorable histology, indicative of a poor prognosis. Heterogeneous nuclear ribonucleoprotein L (hnRNPL) is an RNA-binding protein (RBP) and a regulator of alternative RNA splicing that plays an important role in the occurrence and development of several cancers. Methods: Next generation sequencing technologies was used to discovery differentially expressed genes between WT and adjacent nontumors. The gene ontology (GO) analysis was performed to uncover the biological functions of differentially expressed genes, and the kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis was applied to find out the related signal pathways. Expression levelsof hnRNPL with WT tissues and cells were determined by RT-qPCR.After silencing hnRNPL, the expression of hnRNPL, p53 and Bcl-2 were detected by RT-qPCR and Western blot in WT cell line. The regulatory effects of hnRNPLon proliferative and apoptotic potentials of WT cells were evaluated by MTT and flow cytometry, respectively. RNA-binding protein immuno-precipitation was used to confirm the direct interaction of hnRNPL with p53 mRNA. Mouse xenograft models ofhnRNPL knockdown were established to test the functions in the growth of WT in vivo. Results: High levels of hnRNPL were expressed in WT tissues and cells. Functional analysis revealed that hnRNPL silencing suppressed cell proliferation and promoted cell apoptosis in WT. Molecular mechanism exploration indicated that hnRNPL directly targeted p53. Moreover, knockdown of hnRNPL inhibited the expression of p53 and Bcl2 in WT. Additionally, hnRNPL silencing inhibited the growth of xenograft tumors in vivo. Conclusion: HnRNPL act as p53 mRNA-binding protein, which plays an important role in the proliferation and apoptosis of WT through p53 and Bcl2 pathways and these findings provide new insights into the mechanism of WT pathogenesis.
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Affiliation(s)
- Xin Luo
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing 400014, People's Republic of China
| | - Changkai Deng
- Department of Pediatric Surgery, Chengdu Women and Children's Central Hospital, Chengdu 610073, People's Republic of China
| | - Feng Liu
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing 400014, People's Republic of China.,Department of Pediatric Urology Surgery, Children's Hospital of Chongqing Medical University, Chongqing 400014, People's Republic of China
| | - Xing Liu
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing 400014, People's Republic of China.,Department of Pediatric Urology Surgery, Children's Hospital of Chongqing Medical University, Chongqing 400014, People's Republic of China
| | - Tao Lin
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing 400014, People's Republic of China.,Department of Pediatric Urology Surgery, Children's Hospital of Chongqing Medical University, Chongqing 400014, People's Republic of China
| | - Dawei He
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing 400014, People's Republic of China.,Department of Pediatric Urology Surgery, Children's Hospital of Chongqing Medical University, Chongqing 400014, People's Republic of China
| | - Guanghui Wei
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing 400014, People's Republic of China.,Department of Pediatric Urology Surgery, Children's Hospital of Chongqing Medical University, Chongqing 400014, People's Republic of China
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8
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Zhao X, Liu X, Wang G, Wen X, Zhang X, Hoffman AR, Li W, Hu JF, Cui J. Loss of insulin-like growth factor II imprinting is a hallmark associated with enhanced chemo/radiotherapy resistance in cancer stem cells. Oncotarget 2018; 7:51349-51364. [PMID: 27275535 PMCID: PMC5239480 DOI: 10.18632/oncotarget.9784] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 05/13/2016] [Indexed: 02/06/2023] Open
Abstract
Insulin-like growth factor II (IGF2) is maternally imprinted in most tissues, but the epigenetic regulation of the gene in cancer stem cells (CSCs) has not been defined. To study the epigenetic mechanisms underlying self-renewal, we isolated CSCs and non-CSCs from colon cancer (HT29, HRT18, HCT116), hepatoma (Hep3B), breast cancer (MCF7) and prostate cancer (ASPC) cell lines. In HT29 and HRT18 cells that show loss of IGF2 imprinting (LOI), IGF2 was biallelically expressed in the isolated CSCs. Surprisingly, we also found loss of IGF2 imprinting in CSCs derived from cell lines HCT116 and ASPC that overall demonstrate maintenance of IGF2 imprinting. Using chromatin conformation capture (3C), we found that intrachromosomal looping between the IGF2 promoters and the imprinting control region (ICR) was abrogated in CSCs, in parallel with loss of IGF2 imprinting in these CSCs. Loss of imprinting led to increased IGF2 expression in CSCs, which have a higher rate of colony formation and greater resistance to chemotherapy and radiotherapy in vitro. These studies demonstrate that IGF2 LOI is a common feature in CSCs, even when the stem cells are derived from a cell line in which the general population of cells maintain IGF2 imprinting. This finding suggests that aberrant IGF2 imprinting may be an intrinsic epigenetic control mechanism that enhances stemness, self-renewal and chemo/radiotherapy resistance in cancer stem cells.
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Affiliation(s)
- Xin Zhao
- Cancer Center, The First Hospital of Jilin University, Changchun, Jilin 130021, China
| | - Xiaoliang Liu
- Cancer Center, The First Hospital of Jilin University, Changchun, Jilin 130021, China
| | - Guanjun Wang
- Cancer Center, The First Hospital of Jilin University, Changchun, Jilin 130021, China
| | - Xue Wen
- Cancer Center, The First Hospital of Jilin University, Changchun, Jilin 130021, China
| | - Xiaoying Zhang
- Cancer Center, The First Hospital of Jilin University, Changchun, Jilin 130021, China
| | - Andrew R Hoffman
- Stanford University Medical School, Palo Alto Veterans Institute for Research, Palo Alto, CA 94304, USA
| | - Wei Li
- Cancer Center, The First Hospital of Jilin University, Changchun, Jilin 130021, China
| | - Ji-Fan Hu
- Cancer Center, The First Hospital of Jilin University, Changchun, Jilin 130021, China.,Stanford University Medical School, Palo Alto Veterans Institute for Research, Palo Alto, CA 94304, USA
| | - Jiuwei Cui
- Cancer Center, The First Hospital of Jilin University, Changchun, Jilin 130021, China
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9
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Schofield PN, Kondratowicz M. Evolving paradigms for the biological response to low dose ionizing radiation; the role of epigenetics. Int J Radiat Biol 2017; 94:769-781. [PMID: 29157078 DOI: 10.1080/09553002.2017.1388548] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE In the late 1990s, it had become clear that the long-standing paradigm for the action of radiation on living cells and organisms did not have sufficient power to explain the observed effects of low dose ionizing radiation. The purpose of this commentary is to examine the experiments that lead up to the modification of the classic paradigm consequent on these observations, their historical precedents, and the development of our understanding of the role of epigenetics in low dose radiation effects. RESULTS AND CONCLUSIONS We discuss how parallel advances in epigenetics from developmental biology and cancer studies, and the discovery of epigenetic modifications of chromatin, such as DNA methylation, impacted on the development of an epigenetic paradigm for low dose effects. We also assess the impact of technology development in supporting the paradigm shift. We then examine recent accumulated data on epigenetic modification in response to irradiation since that shift took place, and identify areas where bringing together data from developmental biology and cancer might answer some of the paradoxes and contradictions in this data. We predict that further paradigm shifts are imminent.
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Affiliation(s)
- Paul N Schofield
- a Department of Physiology, Development, and Neuroscience , University of Cambridge , Cambridge , UK
| | - Monika Kondratowicz
- a Department of Physiology, Development, and Neuroscience , University of Cambridge , Cambridge , UK
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10
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Deng C, Dai R, Li X, Liu F. Genetic variation frequencies in Wilms' tumor: A meta-analysis and systematic review. Cancer Sci 2016; 107:690-9. [PMID: 26892980 PMCID: PMC4970837 DOI: 10.1111/cas.12910] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 02/11/2016] [Accepted: 02/12/2016] [Indexed: 12/11/2022] Open
Abstract
Over the last few decades, numerous biomarkers in Wilms' tumor have been confirmed and shown variations in prevalence. Most of these studies were based on small sample sizes. We carried out a meta-analysis of the research published from 1992 to 2015 to obtain more precise and comprehensive outcomes for genetic tests. In the present study, 70 out of 5175 published reports were eligible for the meta-analysis, which was carried out using Stata 12.0 software. Pooled prevalence for gene mutations WT1, WTX, CTNNB1, TP53, MYCN, DROSHA, and DGCR8 was 0.141 (0.104, 0.178), 0.147 (0.110, 0.184), 0.140 (0.100, 0.190), 0.410 (0.214, 0.605), 0.071 (0.041, 0.100), 0.082 (0.048, 0.116), and 0.036 (0.026, 0.046), respectively. Pooled prevalence of loss of heterozygosity at 1p, 11p, 11q, 16q, and 22q was 0.109 (0.084, 0.133), 0.334 (0.295, 0.373), 0.199 (0.146, 0.252), 0.151 (0.129, 0.172), and 0.148 (0.108, 0.189), respectively. Pooled prevalence of 1q and chromosome 12 gain was 0.218 (0.161, 0.275) and 0.273 (0.195, 0.350), respectively. The limited prevalence of currently known genetic alterations in Wilms' tumors indicates that significant drivers of initiation and progression remain to be discovered. Subgroup analyses indicated that ethnicity may be one of the sources of heterogeneity. However, in meta-regression analyses, no study-level characteristics of indicators were found to be significant. In addition, the findings of our sensitivity analysis and possible publication bias remind us to interpret results with caution.
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Affiliation(s)
- Changkai Deng
- Department of Urology Surgery, Children's Hospital of Chongqing Medical University, Ministry of Education Key Laboratory of Child Development and Disorder, Key Laboratory of Pediatrics in Chongqing (CSTC2009CA5002), Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China.,Chengdu Women and Children's Central Hospital, Chengdu, China
| | - Rong Dai
- Chengdu Center for Disease Control and Prevention, Chengdu, China
| | - Xuliang Li
- Department of Urology Surgery, Children's Hospital of Chongqing Medical University, Ministry of Education Key Laboratory of Child Development and Disorder, Key Laboratory of Pediatrics in Chongqing (CSTC2009CA5002), Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Feng Liu
- Department of Urology Surgery, Children's Hospital of Chongqing Medical University, Ministry of Education Key Laboratory of Child Development and Disorder, Key Laboratory of Pediatrics in Chongqing (CSTC2009CA5002), Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
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11
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Wang H, Ge S, Qian G, Li W, Cui J, Wang G, Hoffman AR, Hu JF. Restoration of IGF2 imprinting by polycomb repressive complex 2 docking factor SUZ12 in colon cancer cells. Exp Cell Res 2015; 338:214-21. [PMID: 26407907 DOI: 10.1016/j.yexcr.2015.09.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 09/13/2015] [Accepted: 09/19/2015] [Indexed: 01/09/2023]
Abstract
The insulin-like growth factor II (IGF2) gene is aberrantly expressed in tumors as a result of loss of imprinting (LOI). Reactivation of the normally-suppressed maternal allele may lead to IGF2 upregulation and increased tumor growth, particularly in colon cancer. However, the mechanisms underlying IGF2 LOI in tumors are poorly defined. In this report, we identified polycomb repressive complex 2 (PRC2) docking factor SUZ12 as a critical factor in regulating IGF2 imprinting in tumors. Human colon cancer cell lines (HRT18 and HT29) show loss of IGF2 imprinting. Ectopic expression of SUZ12 restored normal monoallelic expression of IGF2 in these two colon cancer cell lines. Using chromatin immunoprecipitation (ChIP) and chromatin conformation capture (3C), we found that the virally-expressed SUZ12 bound to IGF2 promoters, coordinating with endogenous CTCF to orchestrate a long range intrachromosomal loop between the imprinting control region (ICR) and the IGF2 promoters. The histone methyltransferase EZH2 was recruited to the IGF2 promoters, where it induced H3K27 hypermethylation, suppressing one allele, leading to the restoration of IGF2 imprinting. These data demonstrate that SUZ12 is a key molecule in the regulation of monoallelic expression of IGF2, suggesting a novel epigenetic therapeutic strategy for modulating IGF2 production in human tumors.
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Affiliation(s)
- Haibo Wang
- Institute of Cardiovascular Diseases, Rui Jin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, PR China; Stanford University Medical School, VA Palo Alto Health Care System, Palo Alto, CA 94304, USA
| | - Shengfang Ge
- Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, PR China
| | - Guanxiang Qian
- Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, PR China
| | - Wei Li
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China
| | - Jiuwei Cui
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China
| | - Guanjun Wang
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China
| | - Andrew R Hoffman
- Stanford University Medical School, VA Palo Alto Health Care System, Palo Alto, CA 94304, USA.
| | - Ji-Fan Hu
- Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061, PR China; Stanford University Medical School, VA Palo Alto Health Care System, Palo Alto, CA 94304, USA.
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12
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Fanganiello RD, Ishiy FAA, Kobayashi GS, Alvizi L, Sunaga DY, Passos-Bueno MR. Increased In Vitro Osteopotential in SHED Associated with Higher IGF2 Expression When Compared with hASCs. Stem Cell Rev Rep 2015; 11:635-44. [DOI: 10.1007/s12015-015-9592-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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13
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SUN HUILING, PAN YUQIN, HE BANGSHUN, DENG QIWEN, LI RUI, XU YEQIONG, CHEN JIE, GAO TIANYI, YING HOUQUN, WANG FENG, LIU XIAN, WANG SHUKUI. Gene therapy for human colorectal cancer cell lines with recombinant adenovirus 5 based on loss of the insulin-like growth factor 2 imprinting. Int J Oncol 2015; 46:1759-67. [DOI: 10.3892/ijo.2015.2852] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 12/29/2014] [Indexed: 11/06/2022] Open
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14
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Ozaki S, Kawahara E, Maenaka S, Hoang NV, Oyama T, Imai M, Oda M, Yano S. Distinct allelic expression patterns of imprinted IGF2 in adenocarcinoma and squamous cell carcinoma of the lung. Oncol Lett 2014; 8:2561-2564. [PMID: 25364428 PMCID: PMC4214443 DOI: 10.3892/ol.2014.2572] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 08/22/2014] [Indexed: 11/30/2022] Open
Abstract
The insulin-like growth factor 2 gene (IGF2) is an imprinting gene, which mediates cell growth and apoptosis. The loss of imprinting (LOI) of IGF2 has been associated with the development of cancer. In the present study, loss LOI of IGF2 in lung cancer was analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in combination with DNA sequencing of samples collected by laser capture microdissection. The status of each sample was assigned as imprinting when PCR-RFLP revealed only one band or sequence with a single peak; otherwise, the case was classified as LOI. LOI was identified in eight out of 13 adenocarcinoma cases (62%), but was not detected in any of the nine squamous cell carcinoma cases (0%). These results suggest that IGF2 LOI is involved in the molecular pathogenesis of lung adenocarcinoma, but not squamous cell carcinoma, and that LOI may be detected through increased IGF2 expression levels.
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Affiliation(s)
- Satoru Ozaki
- Department of Clinical Laboratory Science, Kanazawa University, Ishikawa 920-0942, Japan
| | - Ei Kawahara
- Department of Clinical Laboratory Science, Kanazawa University, Ishikawa 920-0942, Japan
| | - Shiori Maenaka
- Department of Clinical Laboratory Science, Kanazawa University, Ishikawa 920-0942, Japan
| | - Nguyen Viet Hoang
- Department of Clinical Laboratory Science, Kanazawa University, Ishikawa 920-0942, Japan
| | - Takeru Oyama
- Department of Pathology, Kanazawa University, Ishikawa 920-0942, Japan
| | - Miwa Imai
- Department of Health Science, Ishikawa Prefectural Nursing University, Ishikawa 929-1212, Japan
| | - Makoto Oda
- Department of Lung Surgery, Kanazawa University Hospital, Ishikawa 920-8641, Japan
| | - Seiji Yano
- Department of Internal Medicine, Kanazawa University Cancer Research Institute, Ishikawa 920-1192, Japan
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15
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Kameswaran V, Kaestner KH. The Missing lnc(RNA) between the pancreatic β-cell and diabetes. Front Genet 2014; 5:200. [PMID: 25071830 PMCID: PMC4077016 DOI: 10.3389/fgene.2014.00200] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 06/15/2014] [Indexed: 01/15/2023] Open
Abstract
Diabetes mellitus represents a group of complex metabolic diseases that result in impaired glucose homeostasis, which includes destruction of β-cells or the failure of these insulin-secreting cells to compensate for increased metabolic demand. Despite a strong interest in characterizing the transcriptome of the different human islet cell types to understand the molecular basis of diabetes, very little attention has been paid to the role of long non-coding RNAs (lncRNAs) and their contribution to this disease. Here we summarize the growing evidence for the potential role of these lncRNAs in β-cell function and dysregulation in diabetes, with a focus on imprinted genomic loci.
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Affiliation(s)
- Vasumathi Kameswaran
- Department of Genetics and Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA
| | - Klaus H Kaestner
- Department of Genetics and Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA
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16
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Torrezan GT, Ferreira EN, Nakahata AM, Barros BDF, Castro MTM, Correa BR, Krepischi ACV, Olivieri EHR, Cunha IW, Tabori U, Grundy PE, Costa CML, de Camargo B, Galante PAF, Carraro DM. Recurrent somatic mutation in DROSHA induces microRNA profile changes in Wilms tumour. Nat Commun 2014; 5:4039. [PMID: 24909261 PMCID: PMC4062040 DOI: 10.1038/ncomms5039] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 05/06/2014] [Indexed: 12/16/2022] Open
Abstract
Wilms tumour (WT) is an embryonal kidney neoplasia for which very few driver genes have
been identified. Here we identify DROSHA mutations in 12% of WT samples (26/222) using whole-exome
sequencing and targeted sequencing of 10 microRNA (miRNA)-processing genes. A recurrent
mutation (E1147K) affecting a metal-binding residue of the RNase IIIb domain is detected in
81% of the DROSHA-mutated tumours.
In addition, we identify non-recurrent mutations in other genes of this pathway
(DGCR8, DICER1, XPO5 and TARBP2). By assessing the miRNA expression pattern of the
DROSHA-E1147K-mutated tumours
and cell lines expressing this mutation, we determine that this variant leads to a
predominant downregulation of a subset of miRNAs. We confirm that the downregulation occurs
exclusively in mature miRNAs and not in primary miRNA transcripts, suggesting that the
DROSHA E1147K mutation affects
processing of primary miRNAs. Our data underscore the pivotal role of the miRNA biogenesis
pathway in WT tumorigenesis, particularly the major miRNA-processing gene DROSHA. Wilms tumour (WT) is the most common paediatric kidney cancer and few driver
genes related to its development have been identified. Here, the authors identify
DROSHA mutations that may contribute to WT tumorigenesis through their effect on
primary microRNA processing.
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Affiliation(s)
- Giovana T Torrezan
- 1] Genomics and Molecular Biology Laboratory, International Research Center, A. C. Camargo Cancer Center, São Paulo, S.P., 01508-010, Brazil [2]
| | - Elisa N Ferreira
- 1] Genomics and Molecular Biology Laboratory, International Research Center, A. C. Camargo Cancer Center, São Paulo, S.P., 01508-010, Brazil [2]
| | - Adriana M Nakahata
- Genomics and Molecular Biology Laboratory, International Research Center, A. C. Camargo Cancer Center, São Paulo, S.P., 01508-010, Brazil
| | - Bruna D F Barros
- Genomics and Molecular Biology Laboratory, International Research Center, A. C. Camargo Cancer Center, São Paulo, S.P., 01508-010, Brazil
| | - Mayra T M Castro
- Genomics and Molecular Biology Laboratory, International Research Center, A. C. Camargo Cancer Center, São Paulo, S.P., 01508-010, Brazil
| | - Bruna R Correa
- Centro de Oncologia Molecular, Hospital Sírio-Libanês, São Paulo, S.P., 01308-060, Brazil
| | - Ana C V Krepischi
- Genomics and Molecular Biology Laboratory, International Research Center, A. C. Camargo Cancer Center, São Paulo, S.P., 01508-010, Brazil
| | - Eloisa H R Olivieri
- Genomics and Molecular Biology Laboratory, International Research Center, A. C. Camargo Cancer Center, São Paulo, S.P., 01508-010, Brazil
| | - Isabela W Cunha
- Department of Pathology, A. C. Camargo Cancer Center, São Paulo, S.P., 01509-900, Brazil
| | - Uri Tabori
- Department of Pediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada M5G 1X8
| | - Paul E Grundy
- Cancer Control Alberta, Alberta Health Services, Edmonton, Alberta, Canada AB T5J 3H1
| | - Cecilia M L Costa
- Department of Pediatrics, A. C. Camargo Cancer Center, São Paulo, S.P., 01509-010, Brazil
| | - Beatriz de Camargo
- Pediatric Hematology-Oncology Research Program, Instituto Nacional de Cancer, INCA, Rio de Janeiro, R.J., 20231-050, Brazil
| | - Pedro A F Galante
- Centro de Oncologia Molecular, Hospital Sírio-Libanês, São Paulo, S.P., 01308-060, Brazil
| | - Dirce M Carraro
- Genomics and Molecular Biology Laboratory, International Research Center, A. C. Camargo Cancer Center, São Paulo, S.P., 01508-010, Brazil
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17
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18
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Dynkevich Y, Rother KI, Whitford I, Qureshi S, Galiveeti S, Szulc AL, Danoff A, Breen TL, Kaviani N, Shanik MH, Leroith D, Vigneri R, Koch CA, Roth J. Tumors, IGF-2, and hypoglycemia: insights from the clinic, the laboratory, and the historical archive. Endocr Rev 2013; 34:798-826. [PMID: 23671155 DOI: 10.1210/er.2012-1033] [Citation(s) in RCA: 136] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Tumors of mesenchymal and epithelial origin produce IGF-2, which activates pathways in the tumors. In a minority of patients, the tumors (hepatomas, fibromas, and fibrosarcomas are the most common among many) release into the circulation enough IGF-2-related peptides to mimic the fasting hypoglycemia characteristic of patients with insulin-producing islet-cell tumors. Rarely, markedly elevated IGF-2 levels produce somatic changes suggestive of acromegaly. Typically, the elevated IGF-2 levels are associated with suppressed plasma levels of insulin, IGF-1, and GH. Complicating the pathophysiology are the IGF binding proteins (IGFBPs) that can bind IGF-2 and IGF-1, modifying hormone metabolism and action. IGFBP concentrations are often altered in the presence of these tumors. At the cellular level, the 3 hormone-related ligands, IGF-2, IGF-1, and insulin, all bind to 4 (or more) types of IGF-1 receptor (IGF-1R) and insulin receptor (IR). Each receptor has its own characteristic affinity for each ligand, a tyrosine kinase, and overlapping profiles of action in the target cells. The IGF-2R, in addition to binding mannose-6-phosphate-containing proteins, provides an IGF-2 degradation pathway. Recent evidence suggests IGF-2R involvement also in signal transduction. Surgery, the treatment of choice, can produce a cure. For patients not cured by surgery, multiple therapies exist, for the tumor and for hypoglycemia. Potential future therapeutic approaches are sketched. From 1910 to 1930, hypoglycemia, insulin, insulinomas, and non-islet-cell tumors were recognized. The latter third of the century witnessed the emergence of the immunoassay for insulin; the IGFs, their binding proteins, and assays to measure them; and receptors for the insulin-related peptides as well as the intracellular pathways beyond the receptor. In closing, we replace non-islet-cell tumor hypoglycemia, an outdated and misleading label, with IGF-2-oma, self-explanatory and consistent with names of other hormone-secreting tumors.
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Affiliation(s)
- Yevgeniya Dynkevich
- MD, FACP, Investigator, Feinstein Institute for Medical Research, Laboratory of Diabetes and Diabetes-Related Research, 350 Community Drive, Manhasset, NY 11030.
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19
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Akhavanfard S, Vargas SO, Han M, Nitta M, Chang CB, Le LP, Fazlollahi L, Nguyen Q, Ma Y, Cosper A, Dias-Santagata D, Han JY, Bergethon K, Borger DR, Ellisen LW, Pomeroy SL, Haber DA, Iafrate AJ, Rivera MN. Inactivation of the tumor suppressorWTXin a subset of pediatric tumors. Genes Chromosomes Cancer 2013; 53:67-77. [DOI: 10.1002/gcc.22118] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 09/23/2013] [Accepted: 09/24/2013] [Indexed: 12/22/2022] Open
Affiliation(s)
- Sara Akhavanfard
- Department of Pathology; Massachusetts General Hospital; Boston MA
- Cancer Center, Massachusetts General Hospital; Boston MA
- Harvard Medical School; Boston MA
| | - Sara O. Vargas
- Harvard Medical School; Boston MA
- Department of Pathology; Children's Hospital; Boston MA
| | - Moonjoo Han
- Department of Pathology; Massachusetts General Hospital; Boston MA
| | - Mai Nitta
- Department of Pathology; Massachusetts General Hospital; Boston MA
| | - Clarice B. Chang
- Department of Pathology; Massachusetts General Hospital; Boston MA
| | - Long P. Le
- Department of Pathology; Massachusetts General Hospital; Boston MA
- Harvard Medical School; Boston MA
| | - Ladan Fazlollahi
- Department of Pathology; Massachusetts General Hospital; Boston MA
- Harvard Medical School; Boston MA
| | | | | | - Arjola Cosper
- Department of Pathology; Massachusetts General Hospital; Boston MA
| | - Dora Dias-Santagata
- Department of Pathology; Massachusetts General Hospital; Boston MA
- Harvard Medical School; Boston MA
| | - Jae Y. Han
- Department of Pathology; Massachusetts General Hospital; Boston MA
| | | | - Darrell R. Borger
- Cancer Center, Massachusetts General Hospital; Boston MA
- Harvard Medical School; Boston MA
| | - Leif W. Ellisen
- Cancer Center, Massachusetts General Hospital; Boston MA
- Harvard Medical School; Boston MA
| | - Scott L. Pomeroy
- Harvard Medical School; Boston MA
- Department of Neurology; Children's Hospital; Boston MA
| | - Daniel A. Haber
- Cancer Center, Massachusetts General Hospital; Boston MA
- Harvard Medical School; Boston MA
| | - A. John Iafrate
- Department of Pathology; Massachusetts General Hospital; Boston MA
- Harvard Medical School; Boston MA
| | - Miguel N. Rivera
- Department of Pathology; Massachusetts General Hospital; Boston MA
- Cancer Center, Massachusetts General Hospital; Boston MA
- Harvard Medical School; Boston MA
- Broad Institute of Harvard and MIT; Cambridge MA
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20
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Clinically relevant subsets identified by gene expression patterns support a revised ontogenic model of Wilms tumor: a Children's Oncology Group Study. Neoplasia 2013; 14:742-56. [PMID: 22952427 DOI: 10.1593/neo.12714] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Revised: 06/28/2012] [Accepted: 07/04/2012] [Indexed: 01/23/2023] Open
Abstract
Wilms tumors (WT) have provided broad insights into the interface between development and tumorigenesis. Further understanding is confounded by their genetic, histologic, and clinical heterogeneity, the basis of which remains largely unknown. We evaluated 224 WT for global gene expression patterns; WT1, CTNNB1, and WTX mutation; and 11p15 copy number and methylation patterns. Five subsets were identified showing distinct differences in their pathologic and clinical features: these findings were validated in 100 additional WT. The gene expression pattern of each subset was compared with published gene expression profiles during normal renal development. A novel subset of epithelial WT in infants lacked WT1, CTNNB1, and WTX mutations and nephrogenic rests and displayed a gene expression pattern of the postinduction nephron, and none recurred. Three subsets were characterized by a low expression of WT1 and intralobar nephrogenic rests. These differed in their frequency of WT1 and CTNNB1 mutations, in their age, in their relapse rate, and in their expression similarities with the intermediate mesoderm versus the metanephric mesenchyme. The largest subset was characterized by biallelic methylation of the imprint control region 1, a gene expression profile of the metanephric mesenchyme, and both interlunar and perilobar nephrogenic rests. These data provide a biologic explanation for the clinical and pathologic heterogeneity seen within WT and enable the future development of subset-specific therapeutic strategies. Further, these data support a revision of the current model of WT ontogeny, which allows for an interplay between the type of initiating event and the developmental stage in which it occurs.
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21
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Larsson C. Epigenetic aspects on therapy development for gastroenteropancreatic neuroendocrine tumors. Neuroendocrinology 2013; 97:19-25. [PMID: 22456267 DOI: 10.1159/000336087] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 12/10/2011] [Indexed: 01/16/2023]
Abstract
The understanding of epigenetic modifications in gastroenteropancreatic neuroendocrine tumors is a novel and still small field. Activation of the insulin-like growth factor 2 gene locus by loss of imprinting is a classical epigenetic alteration frequently observed in insulinoma. Inactivation of the MEN1 gene, commonly involved in endocrine pancreatic tumors, impairs the association with mixed lineage leukemia involved in histone H3K4me3 methylation. In addition, promising effects on tumor phenotypes such as growth, apoptosis, cell cycle arrest, and expression of neuroendocrine markers have been obtained in vitro for inhibitors of DNA methyltransferase (azacytidine) and histone deacetylation (butyrate, valproic acid, trichostatin A and MS-275). The frequent need for complementary treatments in addition to surgery in this tumor entity supports further efforts in the development and application of drugs acting at general as well as more specific epigenetic alterations.
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Affiliation(s)
- Catharina Larsson
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
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22
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Chen P, Wang SJ, Wang HB, Ren P, Wang XQ, Liu WG, Gu WL, Li DQ, Zhang TG, Zhou CJ. The distribution of IGF2 and IMP3 in osteosarcoma and its relationship with angiogenesis. J Mol Histol 2011; 43:63-70. [DOI: 10.1007/s10735-011-9370-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Accepted: 10/16/2011] [Indexed: 01/16/2023]
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23
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Moisan A, Rivera MN, Lotinun S, Akhavanfard S, Coffman EJ, Cook EB, Stoykova S, Mukherjee S, Schoonmaker JA, Burger A, Kim WJ, Kronenberg HM, Baron R, Haber DA, Bardeesy N. The WTX tumor suppressor regulates mesenchymal progenitor cell fate specification. Dev Cell 2011; 20:583-596. [PMID: 21571217 DOI: 10.1016/j.devcel.2011.03.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 02/11/2011] [Accepted: 03/09/2011] [Indexed: 12/14/2022]
Abstract
WTX is an X-linked tumor suppressor targeted by somatic mutations in Wilms tumor, a pediatric kidney cancer, and by germline inactivation in osteopathia striata with cranial sclerosis, a bone overgrowth syndrome. Here, we show that Wtx deletion in mice causes neonatal lethality, somatic overgrowth, and malformation of multiple mesenchyme-derived tissues, including bone, fat, kidney, heart, and spleen. Inactivation of Wtx at different developmental stages and in primary mesenchymal progenitor cells (MPCs) reveals that bone mass increase and adipose tissue deficiency are due to altered lineage fate decisions coupled with delayed terminal differentiation. Specification defects in MPCs result from aberrant β-catenin activation, whereas alternative pathways contribute to the subsequently delayed differentiation of lineage-restricted cells. Thus, Wtx is a regulator of MPC commitment and differentiation with stage-specific functions in inhibiting canonical Wnt signaling. Furthermore, the constellation of anomalies in Wtx null mice suggests that this tumor suppressor broadly regulates MPCs in multiple tissues.
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Affiliation(s)
- Annie Moisan
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114, USA
| | - Miguel N Rivera
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114, USA.,Department of Pathology, Harvard Medical School, Boston, MA 02114, USA
| | - Sutada Lotinun
- Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA 02115, USA
| | - Sara Akhavanfard
- Department of Pathology, Harvard Medical School, Boston, MA 02114, USA
| | - Erik J Coffman
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114, USA.,Department of Pathology, Harvard Medical School, Boston, MA 02114, USA
| | - Edward B Cook
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114, USA.,Department of Pathology, Harvard Medical School, Boston, MA 02114, USA
| | - Svetlana Stoykova
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114, USA
| | | | - Jesse A Schoonmaker
- Center for Regenerative Medicine, Harvard Medical School, Boston, MA 02114, USA
| | - Alexa Burger
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114, USA
| | - Woo Jae Kim
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114, USA
| | | | - Roland Baron
- Endocrine Unit, Harvard Medical School, Boston, MA 02114, USA.,Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA 02115, USA
| | - Daniel A Haber
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114, USA
| | - Nabeel Bardeesy
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114, USA
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24
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25
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Functional characterization of Wilms tumor-suppressor WTX and tumor-associated mutants. Oncogene 2010; 30:832-42. [PMID: 20956941 DOI: 10.1038/onc.2010.452] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The WTX, Wilms tumor-associated tumor-suppressor gene, is present on the X chromosome and a single WTX mutation may be sufficient to promote carcinogenesis. Unlike the WT1 tumor suppressor, a transcription factor, WTX lacks conserved functional protein domains. To study the function of WTX, we constructed inducible cell lines expressing WTX and tumor-associated WTX mutants. Induction of WTX inhibited cell growth and caused G(1)/G(0) arrest. In contrast, a short, tumor-associated truncation mutant of WTX358 only slightly inhibited cell growth without a significant cell-cycle arrest, although expression of a longer truncation mutant WTX565 led to the growth inhibition and cell-cycle arrest to a similar extent as wild-type WTX. Like WT1, WTX slowed growth and caused cell-cycle arrest through p21 induction. Gene expression profiling showed that these two tumor-suppressors regulated genes in similar pathways, including those implicated in control of the cellular growth, cell cycle, cell death, cancer and cardiovascular system development. When gene expression changes mediated by wild-type WTX were compared with those affected by mutant forms, WTX565 showed a 55% overlap (228 genes) in differentially regulated genes, whereas WTX358 regulated only two genes affected by wild-type WTX, implying that amino-acid residues 358-561 are critical for WTX function.
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26
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Turan N, Katari S, Gerson LF, Chalian R, Foster MW, Gaughan JP, Coutifaris C, Sapienza C. Inter- and intra-individual variation in allele-specific DNA methylation and gene expression in children conceived using assisted reproductive technology. PLoS Genet 2010; 6:e1001033. [PMID: 20661447 PMCID: PMC2908687 DOI: 10.1371/journal.pgen.1001033] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Accepted: 06/17/2010] [Indexed: 11/29/2022] Open
Abstract
Epidemiological studies have reported a higher incidence of rare disorders involving imprinted genes among children conceived using assisted reproductive technology (ART), suggesting that ART procedures may be disruptive to imprinted gene methylation patterns. We examined intra- and inter-individual variation in DNA methylation at the differentially methylated regions (DMRs) of the IGF2/H19 and IGF2R loci in a population of children conceived in vitro or in vivo. We found substantial variation in allele-specific methylation at both loci in both groups. Aberrant methylation of the maternal IGF2/H19 DMR was more common in the in vitro group, and the overall variance was also significantly greater in the in vitro group. We estimated the number of trophoblast stem cells in each group based on approximation of the variance of the binomial distribution of IGF2/H19 methylation ratios, as well as the distribution of X chromosome inactivation scores in placenta. Both of these independent measures indicated that placentas of the in vitro group were derived from fewer stem cells than the in vivo conceived group. Both IGF2 and H19 mRNAs were significantly lower in placenta from the in vitro group. Although average birth weight was lower in the in vitro group, we found no correlation between birth weight and IGF2 or IGF2R transcript levels or the ratio of IGF2/IGF2R transcript levels. Our results show that in vitro conception is associated with aberrant methylation patterns at the IGF2/H19 locus. However, very little of the inter- or intra-individual variation in H19 or IGF2 mRNA levels can be explained by differences in maternal DMR DNA methylation, in contrast to the expectations of current transcriptional imprinting models. Extraembryonic tissues of embryos cultured in vitro appear to be derived from fewer trophoblast stem cells. It is possible that this developmental difference has an effect on placental and fetal growth. We have screened a population of children conceived in vitro for epigenetic alterations at two loci that carry parent-of-origin specific methylation marks. We made the observation that epigenetic variability was greater in extraembryonic tissues than embryonic tissues in both groups, as has also been demonstrated in the mouse. The greater level of intra-individual variation in extraembryonic tissues of the in vitro group appears to result from these embryos having fewer trophoblast stem cells. We also made the unexpected observation that variability in parental origin-dependent epigenetic marking was poorly correlated with gene expression. In fact, there is such a high level of inter-individual variation in IGF2 transcript level that the presumed half-fold reduction in IGF2 mRNA accounted for by proper transcriptional imprinting versus complete loss of imprinting would account for less than 5% of the total population variance. Given this level of variability in the expression of an imprinted gene, the presumed operation of “parental conflict” as the selective force acting to maintain imprinted gene expression at the IGF2/H19 locus in the human should be revisited.
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Affiliation(s)
- Nahid Turan
- Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Sunita Katari
- Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Leigh F. Gerson
- Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Raffi Chalian
- Department of Obstetrics and Gynecology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Michael W. Foster
- Department of Obstetrics and Gynecology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - John P. Gaughan
- Biostatistics Consulting Center, Temple University School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Christos Coutifaris
- Department of Obstetrics and Gynecology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Carmen Sapienza
- Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, Pennsylvania, United States of America
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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27
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Abstract
Epigenetic regulation is important for stable maintenance of cell identity. For continued function of organs and tissues, illegitimate changes in cell identity must be avoided. Failure to do so can trigger tumour development and disease. How epigenetic patterns are established during cell differentiation has been explored by studying model systems such as X inactivation. Mammals balance the X-linked gene dosage between the sexes by silencing of one of the two X chromosomes in females. This is initiated by expression of the non-coding X-inactive specific transcript (Xist) RNA and depends on specific cellular contexts, in which essential silencing factors are expressed. Normally X inactivation is initiated in early embryogenesis, but recent reports identified instances where Xist is expressed and can initiate gene repression. Here we describe the features that characterize the cellular permissivity to initiation of X inactivation and note that these can also occur in cancer cells and in specific haematopoietic progenitors. We propose that embryonic pathways for epigenetic regulation are re-established in adult progenitor cells and tumour cells. Understanding their reactivation will deepen our understanding of tumourigenesis and may be exploited for cancer therapy.
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Affiliation(s)
- Ruben Agrelo
- Research Institute of Molecular Pathology, Vienna, Austria.
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Lampl M, Kusanovic JP, Erez O, Gotsch F, Espinoza J, Goncalves L, Lee W, Gomez R, Nien JK, Frongillo EA, Romero R. Growth perturbations in a phenotype with rapid fetal growth preceding preterm labor and term birth. Am J Hum Biol 2010; 21:782-92. [PMID: 19298010 DOI: 10.1002/ajhb.20880] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The variability in fetal growth rates and gestation duration in humans is not well understood. Of interest are women presenting with an episode of preterm labor and subsequently delivering a term neonate, who is small relative to peers of similar gestational age. To further understand these relationships, fetal growth patterns predating an episode of preterm labor were investigated. Retrospective analysis of fetal biometry assessed by serial ultrasound in a prospectively studied sample of pregnancies in Santiago, Chile, tested the hypothesis that fetal growth patterns among uncomplicated pregnancies (n = 3,706) and those with an episode of preterm labor followed by term delivery (n = 184) were identical across the time intervals 16-22 weeks, 22-28 weeks, and 28-34 weeks in a multilevel mixed-effects regression. The hypothesis was not supported. Fetal weight growth rate was faster from 16 weeks among pregnancies with an episode of preterm labor (P < 0.05), declined across midgestation (22-28 weeks, P < 0.05), and rebounded between 28 and 34 weeks (P = 0.06). This was associated with perturbations in abdominal circumference growth and proportionately larger biparietal diameter from 22 gestational weeks (P = 0.03), greater femur (P = 0.01), biparietal diameter (P = 0.001) and head circumference (P = 0.02) dimensions relative to abdominal circumference across midgestation (22-28 weeks), followed by proportionately smaller femur diaphyseal length (P = 0.02) and biparietal diameter (P = 0.03) subsequently. A distinctive rapid growth phenotype characterized fetal growth preceding an episode of preterm labor among this sample of term-delivered neonates. Perturbations in abdominal circumference growth and patterns of proportionality suggest an altered growth strategy pre-dating the preterm labor episode.
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Affiliation(s)
- Michelle Lampl
- Department of Anthropology, Emory University, Atlanta, Georgia, USA.
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29
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Abstract
Profound changes in the epigenetic landscape of cancer cells underlie the development of human malignancies. These changes include large-scale DNA methylation changes throughout the genome as well as alterations in the compendium of post-translational chromatin modifications. Epigenetic aberrations impact multiple steps during tumorigenesis, ultimately promoting the selection of neoplastic cells with increasing pathogenicity. Identification of these alterations for use as predictive and prognostic biomarkers has been a highly sought after goal. Recent advances in the field have not only greatly expanded our knowledge of the epigenetic changes driving neoplasia but also demonstrated their significant clinical utility as cancer biomarkers. These biomarkers have proved to be useful for identifying patients whose malignancies are sensitive to specific cytotoxic chemotherapies and may hold promise for predicting which patients will benefit from newer targeted agents directed at oncogenes. The recent application of global analysis strategies has further accelerated our understanding of the epigenome and promises to enhance the identification of epigenomic programs underlying cancer progression and treatment response.
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Affiliation(s)
- Timothy A Chan
- Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
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Pathak S, Saxena M, D'Souza R, Balasinor NH. Disrupted imprinting status at the H19 differentially methylated region is associated with the resorbed embryo phenotype in rats. Reprod Fertil Dev 2010; 22:939-48. [DOI: 10.1071/rd09154] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Accepted: 01/20/2010] [Indexed: 12/17/2022] Open
Abstract
Igf2, an imprinted gene that is paternally expressed in embryos, encodes an embryonic growth factor. An important regulator of Igf2 expression is methylation of the H19 differentially methylated region (DMR). A significant association has been observed between sperm methylation status at the H19 DMR and post-implantation loss. In addition, tamoxifen treatment has been shown to increase post-implantation loss and reduce DNA methylation at the H19 DMR in rat spermatozoa. Because this DMR is a primary DMR transmitting epigenetic imprint information from the gametes to the embryo, the aim of the present study was to determine the imprinting status of H19 DMR in post-implantation normal and resorbed embryos (F1) and to compare it with the H19 DMR in the spermatozoa of the respective sires. Analysis of the H19 DMR revealed methylation errors in resorbed embryo that were also observed in their sires' spermatozoa in the control and tamoxifen-treated groups. Expression analysis of the reciprocally imprinted genes Igf2 and H19 showed significant downregulation of Igf2 protein without any effect on H19 transcript levels in the resorbed embryos. The results indicate an association between disrupted imprinting status at the H19 DMR in resorbed embryos and the spermatozoa from their respective sires regardless of treatment, implying a common mechanism of resorption. The results demonstrate transmission of methylation errors at the Igf2–H19 locus through the paternal germline to the subsequent generation, emphasising the role of paternal factors during embryogenesis.
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Vu TH, Nguyen AH, Hoffman AR. Loss of IGF2 imprinting is associated with abrogation of long-range intrachromosomal interactions in human cancer cells. Hum Mol Genet 2009; 19:901-19. [PMID: 20015958 DOI: 10.1093/hmg/ddp558] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Nuclear architecture and chromatin geography are important factors in the regulation of gene expression, as these components may play a vital epigenetic role both in normal physiology as well as in the initiation and progression of malignancies. Using a modification of the chromosome conformation capture (3C) technique, we examined long-range chromatin interactions of the imprinted human IGF2 gene. We demonstrate that numerous intrachromosomal interactions occur along both parental alleles in normal tissues, where the IGF2 is paternally expressed, as well as in normal liver where gene expression is biallelic. Long-range and allele-specific interactions occur between the IGF2/H19 imprinting control region-1 (ICR1) and ICR2, a region which regulates an imprinted gene cluster nearly a megabase distant from IGF2. Loss of genomic imprinting is a common epigenetic event in cancer, and long-range interactions have not been examined in malignant cells. In cancer cell lines in which IGF2 imprinting is maintained (MOI), essentially all of the 3C interactions seen in normal cells were preserved. However, in cells in which IGF2 imprinting was lost (LOI), nearly all of the long-range chromatin interactions involving IGF2 were abrogated. A three-dimensional computer model depicts the physical interactions between the IGF2 promoter and ICR1 in MOI cells, while the model of LOI lung cancer cells is flattened with few long-range interactions. This dramatic change in the three-dimension configuration of the chromatin at the IGF2 locus in LOI cancer cells suggests that the loss of imprinting may lead to a variety of changes in gene expression in addition to changes in IGF2 transcription.
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Affiliation(s)
- Thanh H Vu
- VA Palo Alto Health Care System and Stanford University, Palo Alto, CA 94301, USA
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Kim NH, Lee CH, Lee AY. H19 RNA downregulation stimulated melanogenesis in melasma. Pigment Cell Melanoma Res 2009; 23:84-92. [DOI: 10.1111/j.1755-148x.2009.00659.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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33
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Lefebvre L, Mar L, Bogutz A, Oh-McGinnis R, Mandegar MA, Paderova J, Gertsenstein M, Squire JA, Nagy A. The interval between Ins2 and Ascl2 is dispensable for imprinting centre function in the murine Beckwith-Wiedemann region. Hum Mol Genet 2009; 18:4255-67. [PMID: 19684026 DOI: 10.1093/hmg/ddp379] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Imprinted genes are commonly clustered in domains across the mammalian genome, suggesting a degree of coregulation via long-range coordination of their monoallelic transcription. The distal end of mouse chromosome 7 (Chr 7) contains two clusters of imprinted genes within a approximately 1 Mb domain. This region is conserved on human 11p15.5 where it is implicated in the Beckwith-Wiedemann syndrome. In both species, imprinted regulation requires two critical cis-acting imprinting centres, carrying different germline epigenetic marks and mediating imprinted expression in the proximal and distal sub-domains. The clusters are separated by a region containing the gene for tyrosine hydroxylase (Th) as well as a high density of short repeats and retrotransposons in the mouse. We have used the Cre-loxP recombination system in vivo to engineer an interstitial deletion of this approximately 280-kb intervening region previously proposed to participate in the imprinting mechanism or to act as a boundary between the two sub-domains. The deletion allele, Del(7AI), is silent with respect to epigenetic marking at the two flanking imprinting centres. Reciprocal inheritance of Del(7AI) demonstrates that the deleted region, which represents more than a quarter of the previously defined imprinted domain, is associated with intrauterine growth restriction in maternal heterozygotes. In homozygotes, the deficiency behaves as a Th null allele and can be rescued pharmacologically by bypassing the metabolic requirement for TH in utero. Our results show that the deleted interval is not required for normal imprinting on distal Chr 7 and uncover a new imprinted growth phenotype.
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Affiliation(s)
- Louis Lefebvre
- Department of Medical Genetics and Molecular Epigenetics Group, Life Sciences Institute, The University of British Columbia, Vancouver, BC, Canada.
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Avnet S, Sciacca L, Salerno M, Gancitano G, Cassarino MF, Longhi A, Zakikhani M, Carboni JM, Gottardis M, Giunti A, Pollak M, Vigneri R, Baldini N. Insulin receptor isoform A and insulin-like growth factor II as additional treatment targets in human osteosarcoma. Cancer Res 2009; 69:2443-52. [PMID: 19258511 DOI: 10.1158/0008-5472.can-08-2645] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Despite the frequent presence of an insulin-like growth factor I receptor (IGFIR)-mediated autocrine loop in osteosarcoma (OS), interfering with this target was only moderately effective in preclinical studies. Here, we considered other members of the IGF system that might be involved in the molecular pathology of OS. We found that, among 45 patients with OS, IGF-I and IGFBP-3 serum levels were significantly lower, and IGF-II serum levels significantly higher, than healthy controls. Increased IGF-II values were associated with a decreased disease-free survival. After tumor removal, both IGF-I and IGF-II levels returned to normal values. In 23 of 45 patients, we obtained tissue specimens and found that all expressed high mRNA level of IGF-II and >IGF-I. Also, isoform A of the insulin receptor (IR-A) was expressed at high level in addition to IGFIR and IR-A/IGFIR hybrids receptors (HR(A)). These receptors were also expressed in OS cell lines, and simultaneous impairment of IGFIR, IR, and Hybrid-Rs by monoclonal antibodies, siRNA, or the tyrosine kinase inhibitor BMS-536924, which blocks both IGFIR and IR, was more effective than selective anti-IGFIR strategies. Also, anti-IGF-II-siRNA treatment in low-serum conditions significantly inhibited MG-63 OS cells that have an autocrine circuit for IGF-II. In summary, IGF-II rather than IGF-I is the predominant growth factor produced by OS cells, and three different receptors (IR-A, HR(A), and IGFIR) act complementarily for an IGF-II-mediated constitutive autocrine loop, in addition to the previously shown IGFIR/IGF-I circuit. Cotargeting IGFIR and IR-A is more effective than targeting IGF-IR alone in inhibiting OS growth.
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Affiliation(s)
- Sofia Avnet
- Laboratory for Pathophysiology, Rizzoli Orthopaedic Institute, Bologna, Italy.
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36
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Lampl M, Kusanovic JP, Erez O, Espinoza J, Gotsch F, Goncalves L, Hassan S, Gomez R, Nien JK, Frongillo EA, Romero R. Early rapid growth, early birth: accelerated fetal growth and spontaneous late preterm birth. Am J Hum Biol 2009; 21:141-50. [PMID: 18988282 PMCID: PMC3166224 DOI: 10.1002/ajhb.20840] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The past two decades in the United States have seen a 24% rise in spontaneous late preterm delivery (34-36 weeks) of unknown etiology. This study tested the hypothesis that fetal growth was identical prior to spontaneous preterm (n = 221, median gestational age at birth 35.6 weeks) and term (n = 3706) birth among pregnancies followed longitudinally in Santiago, Chile. The hypothesis was not supported: Preterm-delivered fetuses were significantly larger than their term-delivered peers by mid-second trimester in estimated fetal weight, head, limb, and abdominal dimensions, and they followed different growth trajectories. Piecewise regression assessed time-specific differences in growth rates at 4-week intervals from 16 weeks. Estimated fetal weight and abdominal circumference growth rates slowed at 20 weeks among the preterm-delivered, only to match and/or exceed their term-delivered peers at 24-28 weeks. After an abrupt growth rate decline at 28 weeks, fetuses delivered preterm did so at greater population-specific sex and age-adjusted birth weight percentiles than their peers from uncomplicated pregnancies (P < 0.01). Growth rates predicted birth timing: one standard score of estimated fetal weight increased the odds ratio for late preterm birth from 2.8 prior to 23 weeks, to 3.6 (95% confidence interval, 1.82-7.11, P < 0.05) between 23 and 27 weeks. After 27 weeks, increasing size was protective (OR: 0.56, 95% confidence interval, 0.38-0.82, P = 0.003). These data document, for the first time, a distinctive fetal growth pattern across gestation preceding spontaneous late preterm birth, identify the importance of mid-gestation for alterations in fetal growth, and add perspective on human fetal biological variability.
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Affiliation(s)
- Michelle Lampl
- Department of Anthropology, Emory University, Atlanta, Georgia 30322, USA
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37
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Petkov SG, Reh WA, Anderson GB. Methylation changes in porcine primordial germ cells. Mol Reprod Dev 2009; 76:22-30. [PMID: 18425774 DOI: 10.1002/mrd.20926] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Epigenetic re-programming is an important event in the development of primordial germ cells (PGC) into functional gametes, characterized by genome-wide erasure of DNA methylation and re-establishment of epigenetic marks, a process essential for restoration of the potential for totipotency. In this study changes in the methylation status of centromeric repeats and two IGF2-H19 differentially methylated domain (DMD) sequences were examined in porcine PGC between Days 24 and 31 of pregnancy. The methylation levels of centromeric repeats and IGF2-H19 DMD sequences decreased rapidly from Days 24 to 28 in both male and female PGC. At Days 30 and 31 of pregnancy centromeric repeats and IGF2-H19 DMD sequences acquired new methylation in male PGC, while in female PGC these sequences were completely demethylated by Day 30 and remained hypomethylated at Day 31. To characterize methylation changes that PGC undergo in culture, the methylation status of embryonic germ cells (EGCs) derived from PGC at Day 26 of pregnancy was examined. Centromeric repeats and IGF2-H19 DMD sequences were similarly methylated in both male and female EGC and hypermethylated in female EGC compared with female PGC at the same embryonic age. Our results show that, similar to murine PGC, porcine PGC undergo genome-wide DNA demethylation shortly after arrival in the genital ridges. When placed in culture porcine PGC terminate their demethylation program and may acquire new DNA methylation marks. To our knowledge, this is the first report regarding epigenetic re-programming of genital ridge PGC in the pig.
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Affiliation(s)
- Stoyan G Petkov
- Department of Animal Science, University of California, Davis, California 95616, USA.
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Abstract
Congenital mesoblastic nephroma (CMN) is a rare primary pediatric renal tumor occurring predominantly in infants. There is no known association between CMN and WT1 gene expression and the association of hemihypertrophy and CMN is not well known. We report an infant with isolated hemihypertrophy and WT1-positive CMN, and the results of WT1 immunostaining in 13 other patients with CMN diagnosed over 14 years at SickKids. Of the 14 total patients 3 had positive nuclear immunostaining for WT1. Two patients also expressed WT1 RNA by reverse transcription-polymerase chain reaction. In conclusion, contrary to previous reports, WT1 may be expressed in CMN and CMN can be associated with hemihypertrophy in the absence of Beckwith-Wiedemann syndrome.
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Pathak S, Kedia-Mokashi N, Saxena M, D'Souza R, Maitra A, Parte P, Gill-Sharma M, Balasinor N. Effect of tamoxifen treatment on global and insulin-like growth factor 2-H19 locus-specific DNA methylation in rat spermatozoa and its association with embryo loss. Fertil Steril 2008; 91:2253-63. [PMID: 18778817 DOI: 10.1016/j.fertnstert.2008.07.1709] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2008] [Revised: 06/13/2008] [Accepted: 07/09/2008] [Indexed: 10/21/2022]
Abstract
OBJECTIVE To determine the effect of tamoxifen treatment on global and insulin-like growth factor 2-H19 imprinting control region (Igf2-H19 ICR)-specific DNA methylation in rat spermatozoa and analyze its association with postimplantation loss. DESIGN Experimental prospective study. SETTING Animal research and academic research facility. SUBJECT(S) Male and female 75-day-old Holtzman rats. INTERVENTION(S) Global and Igf2-H19 ICR-specific DNA methylation was analyzed in an epididymal sperm sample in control and tamoxifen-treated rats at a dose of 0.4 mg tamoxifen/kg/day. DNA methylation status was correlated to postimplantation loss in females mated with tamoxifen-treated males. MAIN OUTCOME MEASURE(S) Global sperm DNA methylation level, methylation status of Igf2-H19 ICR in sperm, postimplantation loss. RESULT(S) Tamoxifen treatment significantly reduced methylation at Igf2-H19 ICR in epididymal sperm. However, the global methylation level was not altered. A mating experiment confirmed a significant increase in postimplantation loss upon tamoxifen treatment and showed significant correlation with methylation at Igf2-H19 ICR. CONCLUSION(S) Reduced DNA methylation at Igf2-H19 ICR in rat spermatozoa upon tamoxifen treatment indicated a role of estrogen-associated signaling in the acquisition of paternal-specific imprints during spermatogenesis. In addition, association between DNA methylation and postimplantation loss suggests that errors in paternal imprints at Igf2-H19 ICR could affect embryo development.
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Affiliation(s)
- Shilpa Pathak
- National Institute for Research in Reproductive Health, Indian Council for Medical Research, Mumbai, India
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Holloway DT, Kon M, DeLisi C. In silico regulatory analysis for exploring human disease progression. Biol Direct 2008; 3:24. [PMID: 18564415 PMCID: PMC2464594 DOI: 10.1186/1745-6150-3-24] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2008] [Accepted: 06/18/2008] [Indexed: 12/24/2022] Open
Abstract
Background An important goal in bioinformatics is to unravel the network of transcription factors (TFs) and their targets. This is important in the human genome, where many TFs are involved in disease progression. Here, classification methods are applied to identify new targets for 152 transcriptional regulators using publicly-available targets as training examples. Three types of sequence information are used: composition, conservation, and overrepresentation. Results Starting with 8817 TF-target interactions we predict an additional 9333 targets for 152 TFs. Randomized classifiers make few predictions (~2/18660) indicating that our predictions for many TFs are significantly enriched for true targets. An enrichment score is calculated and used to filter new predictions. Two case-studies for the TFs OCT4 and WT1 illustrate the usefulness of our predictions: • Many predicted OCT4 targets fall into the Wnt-pathway. This is consistent with known biology as OCT4 is developmentally related and Wnt pathway plays a role in early development. • Beginning with 15 known targets, 354 predictions are made for WT1. WT1 has a role in formation of Wilms' tumor. Chromosomal regions previously implicated in Wilms' tumor by cytological evidence are statistically enriched in predicted WT1 targets. These findings may shed light on Wilms' tumor progression, suggesting that the tumor progresses either by loss of WT1 or by loss of regions harbouring its targets. • Targets of WT1 are statistically enriched for cancer related functions including metastasis and apoptosis. Among new targets are BAX and PDE4B, which may help mediate the established anti-apoptotic effects of WT1. • Of the thirteen TFs found which co-regulate genes with WT1 (p ≤ 0.02), 8 have been previously implicated in cancer. The regulatory-network for WT1 targets in genomic regions relevant to Wilms' tumor is provided. Conclusion We have assembled a set of features for the targets of human TFs and used them to develop classifiers for the determination of new regulatory targets. Many predicted targets are consistent with the known biology of their regulators, and new targets for the Wilms' tumor regulator, WT1, are proposed. We speculate that Wilms' tumor development is mediated by chromosomal rearrangements in the location of WT1 targets. Reviewers This article was reviewed by Trey Ideker, Vladimir A. Kuznetsov(nominated by Frank Eisenhaber), and Tzachi Pilpel.
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Affiliation(s)
- Dustin T Holloway
- Molecular Biology Cell Biology and Biochemistry Department, Boston University, 5 Cummington Street, Boston, USA
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Abstract
Silver-Russell syndrome (SRS) is a clinically heterogeneous syndrome characterized by intra-uterine and postnatal growth retardation with spared cranial growth, dysmorphic features and frequent body asymmetry. Various cytogenetic abnormalities have been described in a small number of SRS or SRS-like cases involving chromosomes 7, 8, 11, 15, 17 and 18. However, until recent data became available involving imprinted genes on chromosome 7 and chromosome 11p15, the molecular cause of the syndrome was unknown in most cases. Genomic imprinting is the best example of transcriptional control of genes by epigenetic modifications. Many imprinted genes play key roles in fetal and placental growth and behaviour. This is illustrated in SRS, which can now be considered as a new imprinting disease model. These new findings in the pathophysiology of SRS allow long-term follow-up studies to be performed based on molecular diagnosis. This could help to define appropriate clinical guidelines regarding growth and feeding difficulties.
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Affiliation(s)
- Sylvie Rossignol
- Explorations fonctionnelles endocriniennes, Hôpital Trousseau (APHP); INSERM U515; Université Pierre et Marie Curie-Paris6, 26 avenue du Dr Netter, 75012 Paris, France.
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42
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Loss of imprinting of the insulin-like growth factor 2 gene and risk of colorectal cancer. CURRENT COLORECTAL CANCER REPORTS 2008. [DOI: 10.1007/s11888-008-0012-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Byun HM, Wong HL, Birnstein EA, Wolff EM, Liang G, Yang AS. Examination of IGF2 and H19 loss of imprinting in bladder cancer. Cancer Res 2007; 67:10753-8. [PMID: 18006818 DOI: 10.1158/0008-5472.can-07-0329] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Loss of imprinting (LOI) is a common epigenetic event in cancer and may serve as an early biomarker in some cancers. To obtain a better understanding of LOI, we studied 41 bladder tumors and their adjacent normal bladder mucosa. We found 2/9 (22.2%) cases that displayed LOI of IGF2 and 2/16 (12.5%) that had LOI of H19, as determined by the evaluation of mRNA for biallelic expression. In addition, we examined allele-specific methylation of the differentially methylated regions (DMR) of IGF2 and H19 using a new allele-specific pyrosequencing assay. We found that DNA methylation changes were a common finding (21/30, 70%) in the DMR regions, but could not clearly link DNA methylation changes with LOI as measured by biallelic expression. LOI and allele-specific DNA methylation changes are present in bladder cancer; however, a better understanding of the biology of LOI and its relationship to DNA methylation changes is needed before its use as an epigenetic biomarker.
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Affiliation(s)
- Hyang-Min Byun
- Division of Hematology, University of Southern California/Norris Comprehensive Cancer Center, Los Angeles, California 90033, USA
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44
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Engström W, Shokrai A, Otte K, Granérus M, Gessbo A, Bierke P, Madej A, Sjölund M, Ward A. Transcriptional regulation and biological significance of the insulin like growth factor II gene. Cell Prolif 2007; 31:173-89. [PMID: 9925986 PMCID: PMC6647699 DOI: 10.1111/j.1365-2184.1998.tb01196.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The insulin like growth factors I and II are the most ubiquitous in the mammalian embryo. Moreover they play a pivotal role in the development and growth of tumours. The bioavailability of these growth factors is regulated on a transcriptional as well as on a posttranslational level. The expression of non-signalling receptors as well as binding proteins does further tune the local concentration of IGFs. This paper aims at reviewing how the transcription of the IGF genes is regulated. The biological significance of these control mechanisms will be discussed.
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Affiliation(s)
- W Engström
- Department of Pathology, Faculty of Veterinary Medicine, Swedish University of Agricultural Sciences, Uppsala, Sweden
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45
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Abstract
The practice of clinical oncology historically has been rooted in therapy for established cancers, and over the past decade, early detection of the malignancy has occurred increasingly, allowing an increasing chance of cure by surgical intervention. Cancer prevention has been targeted largely to generic reduction of exposure to environmental carcinogens, such as smoking reduction. However, targeted identification of patients at increased risk and therapeutic tailored intervention in those patients have not taken hold in oncology, despite the enormous success of that approach in preventive cardiology. A paradigm of such a strategy for oncology may be the identification of patients with epigenetic alterations in progenitor cells and intervention before the development of the earliest identifiable neoplasms. We review studies of loss of imprinting of insulin-like growth factor 2 in colorectal cancer as an example of such a target for preventive oncology.
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Affiliation(s)
- Andrew P Feinberg
- Division of Molecular Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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46
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Xu H, Bourne PA, Spaulding BO, Wang HL. High-grade neuroendocrine carcinomas of the lung express K homology domain containing protein overexpressed in cancer but carcinoid tumors do not. Hum Pathol 2007; 38:555-63. [PMID: 17316760 DOI: 10.1016/j.humpath.2006.11.011] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2006] [Revised: 11/10/2006] [Accepted: 11/13/2006] [Indexed: 11/30/2022]
Abstract
K homology domain containing protein overexpressed in cancer (KOC) is a member of the insulin-like growth factor (IGF) messenger RNA-binding protein family and is expressed during embryogenesis and in certain malignancies. KOC, known as L523S and IGF messenger RNA-binding protein 3, was shown to be frequently expressed in high-grade neuroendocrine carcinomas of the lung in our immunohistochemical studies using a monoclonal antibody against human KOC. Specifically, all 10 small cell lung carcinomas (SCLCs) exhibited strong cytoplasmic staining, 9 with diffuse positivity and 1 with focal positivity. Among 14 large cell neuroendocrine carcinomas (LCNECs), 9 exhibited strong and diffuse cytoplasmic staining, and 5 cases showed focal immunoreactivity. In contrast, no KOC was detected in 21 typical and atypical carcinoids, except for one atypical carcinoid with oncocytic cells showing weak cytoplasmic staining. Although SCLCs exhibited a strong and diffuse staining pattern more frequently (90%) than LCNECs (64%), the difference did not reach statistical significance (P = .3408). Interestingly, our immunohistochemical studies demonstrated that IGF-II, reportedly regulated by KOC, was comparably expressed in SCLC, LCNEC, and typical and atypical carcinoids, irrespective of KOC expression status of the tumors. These results support the formulation that KOC may play an important role in the regulation of biologic behavior of high-grade neuroendocrine carcinomas. In addition, detection of KOC expression may be diagnostically useful in distinguishing high-grade neuroendocrine carcinomas from carcinoid tumors. Our findings of equivalent IGF-II expression in KOC-positive SCLC and LCNEC and KOC-negative carcinoid tumors suggest different regulatory mechanisms involved in the control of IGF-II expression in these tumors.
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Affiliation(s)
- Haodong Xu
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY 14642, USA.
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Natrajan R, Reis-Filho JS, Little SE, Messahel B, Brundler MA, Dome JS, Grundy PE, Vujanic GM, Pritchard-Jones K, Jones C. Blastemal Expression of Type I Insulin-Like Growth Factor Receptor in Wilms' Tumors Is Driven by Increased Copy Number and Correlates with Relapse. Cancer Res 2006; 66:11148-55. [PMID: 17145858 DOI: 10.1158/0008-5472.can-06-1931] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Most Wilms' tumors are of low stage, favorable histology, and have a high likelihood of cure with current multimodal therapy. Despite this, there remains a group of patients whose tumors recur for whom intensive salvage regimens result in survival of only 50%. Fitting a Cox proportional hazards model to microarray-based comparative genomic hybridization (aCGH) data on 68 Wilms' tumor samples, we identified a significant correlation between increased copy number at chromosome 15q26.3 insulin-like growth factor I receptor (IGFIR) and tumor relapse (adjusted P = 0.014). Wilms' tumors (13%) exhibited a low-level gain corresponding to three to four copies of the gene by aCGH analysis, 9 of 10 of which exhibited high IGFIR mRNA levels. Although IGFIR protein expression was restricted to the epithelial cells of fetal kidney and Wilms' tumors in most cases, 12% of tumors were also found to express IGFIR in the blastemal compartment. Blastemal IGFIR protein expression was associated with an increased copy number and a shorter relapse-free survival time (P = 0.027, log-rank test). In addition to the membrane localization, IGFIR was localized to the perinuclear region of the blastemal cells in 6% of Wilms' tumors. These data provide evidence that an increase in IGFIR gene copy number results in aberrant expression in the blastemal compartment of some Wilms' tumors and is associated with an adverse outcome in these patients. These findings suggest the possibility of use of targeted agents in the therapy of these children.
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Affiliation(s)
- Rachael Natrajan
- Paediatric Oncology, Institute of Cancer Research/Royal Marsden National Health Service Trust, Sutton, UK
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Feinberg AP. A genetic approach to cancer epigenetics. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2006; 70:335-41. [PMID: 16869770 DOI: 10.1101/sqb.2005.70.027] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In over 20 years since the discovery of altered methylation in cancer, many epigenetic alterations have been found in human cancer, including global and specific gene hypomethylation, hypermethylation, altered chromatin marks, and loss of genomic imprinting. Cancer epigenetics has been limited by questions of cause and effect, since epigenetic changes can arise secondary to the cancer process and its associated widespread changes in gene expression. Furthermore, mutations in the DNA methylation machinery have not been observed in tumors, whereas they have been for chromatin modification. To address the issue of human cancer etiology, we have taken a genetic approach to cancer epigenetics. One line of investigation has been on the disorder Beckwith-Wiedemann syndrome (BWS). We have found that loss of imprinting (LOI) of the autocrine growth factor gene IGF2 and of the untranslated antisense RNA LIT1, within the K(V)LQT1 gene, account for most cases of BWS, and that cancer risk is specifically associated with LOI of IGF2. Wilms' tumors, both in BWS and in the general population, involve LOI leading to an expansion of nephrogenic precursor cells. We have also developed an animal model for the role of LOI of IGF2 in cancer, showing that it cooperates with Apc mutations to increase cancer frequency, consistent with human data suggesting a severalfold increased cancer risk for this common epigenetic variant in the adult population. These data suggest that a major component of cancer risk involves epigenetic changes in normal cells that increase the probability of cancer after genetic mutation. They suggest a model of cancer prevention that involves the epigenetic analysis of normal cells for risk stratification and cancer prevention strategies.
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Affiliation(s)
- A P Feinberg
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Stier S, Neuhaus T, Albers P, Wernert N, Grünewald E, Forkert R, Vetter H, Ko Y. Loss of imprinting of the insulin-like growth factor 2 and the H19 gene in testicular seminomas detected by real-time PCR approach. Arch Toxicol 2006; 80:713-8. [PMID: 16721595 DOI: 10.1007/s00204-006-0087-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2005] [Accepted: 02/28/2006] [Indexed: 11/25/2022]
Abstract
IGF2 and H19 are imprinted genes in normal human tissue, but many studies have observed a loss of imprinting (LOI) of these genes in tumors as an epigenetic alteration of the DNA, that leads to a biallelic expression predisposing cells to carcinogenesis and tumor growth. The aim of this study was to test the reliability of LightCycler-assisted Real-time PCR in detecting LOI of IGF2 and H19 in 39 patients with testicular germ cell tumors by comparing these results with the analysis generated by the golden standard restriction fragment length polymorphism (RFLP). With LightCycler-assisted Real-time PCR for IGF2 44% and for H19 49% of the patients were found to be heterozygous. This was consistent with the results obtained by RFLP, but surprisingly RFLP failed in more than 7% of the patients. In detecting LOI (for IGF2 in 41% and for H19 in 68% of the informative patients) the approach by RFLP was superior, since the results derived from LightCycler-assisted Real-time PCR showed reliable results in 76 and 10% of the samples concerning IGF2 and H19, respectively. Again, no discrepancy between the results obtained by the two methods occurred. In sum, LightCycler-assisted Real-time PCR is a sufficiently working approach for the rapid and reliable detection of heterozygosity of IGF2 or H19 gene and identification of LOI of IGF2 and thus may be helpful in conducting large epidemiological studies. However, for the identification of LOI of the H19 gene in this cohort it possesses only restrictive use.
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Affiliation(s)
- Sebastian Stier
- Medizinische Universitäts-Poliklinik Bonn, Wilhelmstrasse 35-37, 53111 Bonn, Germany
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Gebert C, Wrenzycki C, Herrmann D, Gröger D, Reinhardt R, Hajkova P, Lucas-Hahn A, Carnwath J, Lehrach H, Niemann H. The bovine IGF2 gene is differentially methylated in oocyte and sperm DNA. Genomics 2006; 88:222-9. [PMID: 16644179 DOI: 10.1016/j.ygeno.2006.03.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Revised: 03/16/2006] [Accepted: 03/17/2006] [Indexed: 10/24/2022]
Abstract
The insulin-like growth factor 2 gene (IGF2) encodes an essential growth factor and is imprinted in various mammalian species. Differentially methylated regions (DMRs) are often located within CpG islands and are critically involved in the regulation of monoallelic Igf2 expression in the mouse. Only partial sequence information is available for the bovine IGF2 gene and no DMR has currently been identified. The goal of this study was to identify a DMR within the bovine IGF2 gene as a prerequisite for further studies on gene-specific methylation patterns during preimplantation development. Here we describe the sequence analysis of a CpG-rich DNA fragment from the 5' untranslated region spanning exons and introns 4 and 5 and the identification of a previously unknown DMR in exon 10 of the bovine IGF2 gene. Bisulfite analysis revealed that this DMR is differentially methylated in mature oocytes and sperm. The identification of an intragenic DMR within a developmentally important gene such as the bovine IGF2 gene provides a useful tool to evaluate the methylation patterns of embryos derived in vivo and in vitro. Our study is the first report of a differentially methylated region in a bovine imprinted gene discovered by the analysis of female and male gametes.
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Affiliation(s)
- Claudia Gebert
- Department of Biotechnology, Institute for Animal Breeding, Hoeltystrasse 10, D-31535 Neustadt-Mariensee, Germany
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