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  1. Article ; Online: Mobile drawing methods in landscape research: collaborative drawing in Kathmandu Valley, Nepal

    Fox, Alice / Macpherson, Hannah / Oli, Nischal / Ashmina Ranjit / Thapa, Sangeeta / Aggett, Siân / Church, Andrew

    Landscape Research. 2022 Nov. 17, v. 47, no. 8 p.1009-1023

    2022  

    Abstract: In this paper, we show how mobile drawing methodologies can bring the dynamic, relational and non-representational qualities of landscape encounters to the foreground. The research paper discusses a mobile drawing project that took place in the Kathmandu ...

    Abstract In this paper, we show how mobile drawing methodologies can bring the dynamic, relational and non-representational qualities of landscape encounters to the foreground. The research paper discusses a mobile drawing project that took place in the Kathmandu Valley, Nepal. The project entitled ‘Taxi Guff-Gaff’ invited participants to undertake a collaborative drawing and conversational journey. Mobile drawing together on a bumpy taxi journey required artist participants to move together and literally ‘pay attention to the moment at hand’. In so doing it produced imagery that foregrounds the inherent dynamic quality of all our landscape encounters. We propose that mobile drawing offers an immersive way to relate to the urban landscape and each other and can open up spaces of landscape research that centre on speculative forms of thinking, being, drawing and conversation.
    Keywords landscapes ; research ; Nepal ; Drawing methods ; non-representational theory ; mobile methods ; arts-based research ; visual methods ; critical cartography
    Language English
    Dates of publication 2022-1117
    Size p. 1009-1023.
    Publishing place Routledge
    Document type Article ; Online
    ZDB-ID 2020719-0
    ISSN 0142-6397 ; 1469-9710 ; 0142-6397
    ISSN (online) 0142-6397 ; 1469-9710
    ISSN 0142-6397
    DOI 10.1080/01426397.2022.2090531
    Database NAL-Catalogue (AGRICOLA)

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  2. Article ; Online: High resolution integrative analysis reveals widespread genetic and epigenetic changes after chronic in-vitro acid and bile exposure in Barrett's epithelium cells.

    Bajpai, Manisha / Kessel, Rachel / Bhagat, Tushar / Nischal, Sangeeta / Yu, Yiting / Verma, Amit / Das, Kiron M

    Genes, chromosomes & cancer

    2013  Volume 52, Issue 12, Page(s) 1123–1132

    Abstract: Barrett's epithelium (BE) is a premalignant condition resulting from chronic gastroesophageal reflux that may progress to esophageal adenocarcinoma (EAC). Early intervention holds promise in preventing BE progression. However, identification of high-risk ...

    Abstract Barrett's epithelium (BE) is a premalignant condition resulting from chronic gastroesophageal reflux that may progress to esophageal adenocarcinoma (EAC). Early intervention holds promise in preventing BE progression. However, identification of high-risk BE patients remains challenging due to inadequate biomarkers for early diagnosis. We investigated the effect of prolonged chronic acid and bile exposure on transcriptome, methylome, and mutatome of cells in an in-vitro BE carcinogenesis (BEC) model. Twenty weeks acid and bile exposed cells from the BEC model (BEC20w) were compared with their naïve predecessors HiSeq Illumina based RNA sequencing was performed on RNA from both the cells for gene expression and mutational analysis. HELP Tagging Assay was performed for DNA methylation analysis. Ingenuity pathway, Gene Ontology, and KEGG PATHWAY analyses were then performed on datasets. Widespread aberrant genetic and epigenetic changes were observed in the BEC20w cells. Combinatorial analyses revealed 433 from a total of 863 downregulated genes had accompanying hypermethylation of promoters. Simultaneously, 690 genes from a total of 1,492 were upregulated with accompanying promoter hypomethylation. In addition, 763 mutations were identified on 637 genes. Ingenuity pathway analysis, Gene Ontology, and KEGG PATHWAY analyses associated the genetic and epigenetic changes in BEC20w cells with cellular and biological functions. Integration of high resolution comparative analyses of naïve BAR-T and BEC20w cells revealed striking genetic and epigenetic changes induced by chronic acid and bile exposure that may disrupt normal cellular functions and promote carcinogenesis. This novel study reveals several potential targets for future biomarkers and therapeutic development.
    MeSH term(s) Barrett Esophagus/genetics ; Barrett Esophagus/metabolism ; Barrett Esophagus/pathology ; Bile/metabolism ; Carcinogenesis/genetics ; Carcinogenesis/metabolism ; Carcinogenesis/pathology ; Cells, Cultured ; DNA Methylation ; Epigenesis, Genetic ; Gastric Acid/metabolism ; Glycochenodeoxycholic Acid/pharmacology ; Humans ; Hydrochloric Acid/pharmacology ; Hydrogen-Ion Concentration ; Mutation ; Promoter Regions, Genetic/genetics ; Sequence Analysis, RNA/methods ; Transcriptome
    Chemical Substances Glycochenodeoxycholic Acid (640-79-9) ; Hydrochloric Acid (QTT17582CB)
    Language English
    Publishing date 2013-10-03
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1018988-9
    ISSN 1098-2264 ; 1045-2257
    ISSN (online) 1098-2264
    ISSN 1045-2257
    DOI 10.1002/gcc.22106
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Mechanism of action of lenalidomide in hematological malignancies.

    Kotla, Venumadhav / Goel, Swati / Nischal, Sangeeta / Heuck, Christoph / Vivek, Kumar / Das, Bhaskar / Verma, Amit

    Journal of hematology & oncology

    2009  Volume 2, Page(s) 36

    Abstract: Immunomodulatory drugs lenalidomide and pomalidomide are synthetic compounds derived by modifying the chemical structure of thalidomide to improve its potency and reduce its side effects. Lenalidomide is a 4-amino-glutamyl analogue of thalidomide that ... ...

    Abstract Immunomodulatory drugs lenalidomide and pomalidomide are synthetic compounds derived by modifying the chemical structure of thalidomide to improve its potency and reduce its side effects. Lenalidomide is a 4-amino-glutamyl analogue of thalidomide that lacks the neurologic side effects of sedation and neuropathy and has emerged as a drug with activity against various hematological and solid malignancies. It is approved by FDA for clinical use in myelodysplastic syndromes with deletion of chromosome 5q and multiple myeloma. Lenalidomide has been shown to be an immunomodulator, affecting both cellular and humoral limbs of the immune system. It has also been shown to have anti-angiogenic properties. Newer studies demonstrate its effects on signal transduction that can partly explain its selective efficacy in subsets of MDS. Even though the exact molecular targets of lenalidomide are not well known, its activity across a spectrum of neoplastic conditions highlights the possibility of multiple target sites of action.
    MeSH term(s) Angiogenesis Inhibitors/pharmacology ; Angiogenesis Inhibitors/therapeutic use ; Animals ; Antineoplastic Agents/pharmacology ; Antineoplastic Agents/therapeutic use ; Chromosome Deletion ; Chromosomes, Human, Pair 5 ; Hematologic Neoplasms/drug therapy ; Hematologic Neoplasms/genetics ; Hematologic Neoplasms/immunology ; Hematologic Neoplasms/metabolism ; Humans ; Immunomodulation/drug effects ; Immunomodulation/physiology ; Lenalidomide ; Models, Biological ; Neovascularization, Pathologic/drug therapy ; Neovascularization, Pathologic/pathology ; Signal Transduction/drug effects ; Signal Transduction/immunology ; Signal Transduction/physiology ; Thalidomide/analogs & derivatives ; Thalidomide/pharmacology ; Thalidomide/therapeutic use
    Chemical Substances Angiogenesis Inhibitors ; Antineoplastic Agents ; Thalidomide (4Z8R6ORS6L) ; Lenalidomide (F0P408N6V4)
    Language English
    Publishing date 2009-08-12
    Publishing country England
    Document type Evaluation Study ; Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 2429631-4
    ISSN 1756-8722 ; 1756-8722
    ISSN (online) 1756-8722
    ISSN 1756-8722
    DOI 10.1186/1756-8722-2-36
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Cytokine-Regulated Phosphorylation and Activation of TET2 by JAK2 in Hematopoiesis.

    Jeong, Jong Jin / Gu, Xiaorong / Nie, Ji / Sundaravel, Sriram / Liu, Hui / Kuo, Wen-Liang / Bhagat, Tushar D / Pradhan, Kith / Cao, John / Nischal, Sangeeta / McGraw, Kathy L / Bhattacharyya, Sanchari / Bishop, Michael R / Artz, Andrew / Thirman, Michael J / Moliterno, Alison / Ji, Peng / Levine, Ross L / Godley, Lucy A /
    Steidl, Ulrich / Bieker, James J / List, Alan F / Saunthararajah, Yogen / He, Chuan / Verma, Amit / Wickrema, Amittha

    Cancer discovery

    2019  Volume 9, Issue 6, Page(s) 778–795

    Abstract: Even though the Ten-eleven translocation (TET) enzymes catalyze the generation of 5-hydroxymethylcytosines required for lineage commitment and subsequent differentiation of stem cells into erythroid cells, the mechanisms that link extracellular signals ... ...

    Abstract Even though the Ten-eleven translocation (TET) enzymes catalyze the generation of 5-hydroxymethylcytosines required for lineage commitment and subsequent differentiation of stem cells into erythroid cells, the mechanisms that link extracellular signals to TET activation and DNA hydroxymethylation are unknown. We demonstrate that hematopoietic cytokines phosphorylate TET2, leading to its activation in erythroid progenitors. Specifically, cytokine receptor-associated JAK2 phosphorylates TET2 at tyrosines 1939 and 1964. Phosphorylated TET2 interacts with the erythroid transcription factor KLF1, and this interaction with TET2 is increased upon exposure to erythropoietin. The activating JAK2
    MeSH term(s) Biomarkers ; Cytokines/metabolism ; DNA-Binding Proteins/genetics ; Dioxygenases ; Hematopoiesis/genetics ; Hematopoietic Stem Cells/cytology ; Hematopoietic Stem Cells/metabolism ; Humans ; Janus Kinase 2/metabolism ; Phosphorylation ; Proto-Oncogene Proteins/genetics ; Transcriptional Activation
    Chemical Substances Biomarkers ; Cytokines ; DNA-Binding Proteins ; Proto-Oncogene Proteins ; Dioxygenases (EC 1.13.11.-) ; TET2 protein, human (EC 1.13.11.-) ; JAK2 protein, human (EC 2.7.10.2) ; Janus Kinase 2 (EC 2.7.10.2)
    Language English
    Publishing date 2019-04-03
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2625242-9
    ISSN 2159-8290 ; 2159-8274
    ISSN (online) 2159-8290
    ISSN 2159-8274
    DOI 10.1158/2159-8290.CD-18-1138
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Mechanism of action of lenalidomide in hematological malignancies

    Kotla Venumadhav / Goel Swati / Nischal Sangeeta / Heuck Christoph / Vivek Kumar / Das Bhaskar / Verma Amit

    Journal of Hematology & Oncology, Vol 2, Iss 1, p

    2009  Volume 36

    Abstract: Abstract Immunomodulatory drugs lenalidomide and pomalidomide are synthetic compounds derived by modifying the chemical structure of thalidomide to improve its potency and reduce its side effects. Lenalidomide is a 4-amino-glutamyl analogue of ... ...

    Abstract Abstract Immunomodulatory drugs lenalidomide and pomalidomide are synthetic compounds derived by modifying the chemical structure of thalidomide to improve its potency and reduce its side effects. Lenalidomide is a 4-amino-glutamyl analogue of thalidomide that lacks the neurologic side effects of sedation and neuropathy and has emerged as a drug with activity against various hematological and solid malignancies. It is approved by FDA for clinical use in myelodysplastic syndromes with deletion of chromosome 5q and multiple myeloma. Lenalidomide has been shown to be an immunomodulator, affecting both cellular and humoral limbs of the immune system. It has also been shown to have anti-angiogenic properties. Newer studies demonstrate its effects on signal transduction that can partly explain its selective efficacy in subsets of MDS. Even though the exact molecular targets of lenalidomide are not well known, its activity across a spectrum of neoplastic conditions highlights the possibility of multiple target sites of action.
    Keywords Diseases of the blood and blood-forming organs ; RC633-647.5 ; Specialties of internal medicine ; RC581-951 ; Internal medicine ; RC31-1245 ; Medicine ; R ; DOAJ:Internal medicine ; DOAJ:Medicine (General) ; DOAJ:Health Sciences ; Neoplasms. Tumors. Oncology. Including cancer and carcinogens ; RC254-282 ; DOAJ:Oncology
    Language English
    Publishing date 2009-08-01T00:00:00Z
    Publisher BioMed Central
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Genome-wide hydroxymethylation tested using the HELP-GT assay shows redistribution in cancer.

    Bhattacharyya, Sanchari / Yu, Yiting / Suzuki, Masako / Campbell, Nathaniel / Mazdo, Jozef / Vasanthakumar, Aparna / Bhagat, Tushar D / Nischal, Sangeeta / Christopeit, Maximilian / Parekh, Samir / Steidl, Ulrich / Godley, Lucy / Maitra, Anirban / Greally, John M / Verma, Amit

    Nucleic acids research

    2013  Volume 41, Issue 16, Page(s) e157

    Abstract: 5-hydroxymethylcytosine (5-hmC) is a recently discovered epigenetic modification that is altered in cancers. Genome-wide assays for 5-hmC determination are needed as many of the techniques for 5-methylcytosine (5-mC) determination, including methyl- ... ...

    Abstract 5-hydroxymethylcytosine (5-hmC) is a recently discovered epigenetic modification that is altered in cancers. Genome-wide assays for 5-hmC determination are needed as many of the techniques for 5-methylcytosine (5-mC) determination, including methyl-sensitive restriction digestion and bisulfite sequencing cannot distinguish between 5-mC and 5-hmC. Glycosylation of 5-hmC residues by beta-glucosyl transferase (β-GT) can make CCGG residues insensitive to digestion by MspI. Restriction digestion by HpaII, MspI or MspI after β-GT conversion, followed by adapter ligation, massive parallel sequencing and custom bioinformatic analysis allowed us determine distribution of 5-mC and 5-hmC at single base pair resolution at MspI restriction sites. The resulting HpaII tiny fragment Enrichment by Ligation-mediated PCR with β-GT (HELP-GT) assay identified 5-hmC loci that were validated at global level by liquid chromatography-mass spectrometry (LC-MS) and the locus-specific level by quantitative reverse transcriptase polymerase chain reaction of 5-hmC pull-down DNA. Hydroxymethylation at both promoter and intragenic locations correlated positively with gene expression. Analysis of pancreatic cancer samples revealed striking redistribution of 5-hmC sites in cancer cells and demonstrated enrichment of this modification at many oncogenic promoters such as GATA6. The HELP-GT assay allowed global determination of 5-hmC and 5-mC from low amounts of DNA and with the use of modest sequencing resources. Redistribution of 5-hmC seen in cancer highlights the importance of determination of this modification in conjugation with conventional methylome analysis.
    MeSH term(s) 5-Methylcytosine/analysis ; Animals ; Cell Line, Tumor ; Cell Transformation, Neoplastic ; Cytosine/analogs & derivatives ; Cytosine/analysis ; Cytosine/metabolism ; DNA, Neoplasm/chemistry ; Gene Expression ; Genome, Human ; Genomics/methods ; Glycosyltransferases/metabolism ; Humans ; Mice ; Pancreatic Neoplasms/genetics ; Polymerase Chain Reaction
    Chemical Substances DNA, Neoplasm ; 5-hydroxymethylcytosine (1123-95-1) ; 5-Methylcytosine (6R795CQT4H) ; Cytosine (8J337D1HZY) ; Glycosyltransferases (EC 2.4.-)
    Language English
    Publishing date 2013-07-16
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 186809-3
    ISSN 1362-4962 ; 1362-4954 ; 0301-5610 ; 0305-1048
    ISSN (online) 1362-4962 ; 1362-4954
    ISSN 0301-5610 ; 0305-1048
    DOI 10.1093/nar/gkt601
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Methylome profiling reveals distinct alterations in phenotypic and mutational subgroups of myeloproliferative neoplasms.

    Nischal, Sangeeta / Bhattacharyya, Sanchari / Christopeit, Maximilian / Yu, Yiting / Zhou, Li / Bhagat, Tushar D / Sohal, Davendra / Will, Britta / Mo, Yongkai / Suzuki, Masako / Pardanani, Animesh / McDevitt, Michael / Maciejewski, Jaroslaw P / Melnick, Ari M / Greally, John M / Steidl, Ulrich / Moliterno, Alison / Verma, Amit

    Cancer research

    2012  Volume 73, Issue 3, Page(s) 1076–1085

    Abstract: Even though mutations in epigenetic regulators frequently occur in myeloproliferative neoplasms, their effects on the epigenome have not been well studied. Furthermore, even though primary myelofibrosis (PMF) has a markedly worse prognosis than essential ...

    Abstract Even though mutations in epigenetic regulators frequently occur in myeloproliferative neoplasms, their effects on the epigenome have not been well studied. Furthermore, even though primary myelofibrosis (PMF) has a markedly worse prognosis than essential thrombocytosis or polycythemia vera, the molecular distinctions between these subgroups are not well elucidated. We conducted the HELP (HpaII tiny fragment enriched by LM-PCR) assay to study genome-wide methylation in polycythemia vera, essential thrombocytosis, and PMF samples compared with healthy controls. We determined that polycythemia vera and essential thrombocytosis are characterized by aberrant promoter hypermethylation, whereas PMF is an epigenetically distinct subgroup characterized by both aberrant hyper- and hypomethylation. Aberrant hypomethylation in PMF was seen to occur in non-CpG island loci, showing further qualitative differences between the disease subgroups. The differentially methylated genes in polycythemia vera and essential thrombocytosis were involved predominantly in cell signaling pathways and were enriched for binding sites of GATA1 and other transcription factors. In contrast, aberrantly methylated genes in PMF were involved in inflammatory pathways and were enriched for NF1, LEF1, and other transcription factors. Within the PMF subgroup, cases with ASXL1 disruptions formed an epigenetically distinct subgroup with relatively increased methylation. Cases of myeloproliferative neoplasms (MPN) with TET2 mutations showed decreased levels of hydroxymethylation and distinct set of hypermethylated genes. In contrast, the JAK2V617F mutation did not drive epigenetic clustering within MPNs. Finally, the significance of aberrant methylation was shown by sensitivity of MPN-derived cell lines to decitabine. These results show epigenetic differences between PMF and polycythemia vera/essential thrombocytosis and reveal methylomic signatures of ASXL1 and TET2 mutations.
    MeSH term(s) Adult ; Aged ; Aged, 80 and over ; Azacitidine/analogs & derivatives ; Azacitidine/pharmacology ; Cell Line, Tumor ; DNA Methylation ; DNA-Binding Proteins/genetics ; Decitabine ; Dioxygenases ; Female ; Humans ; Janus Kinase 2/genetics ; Male ; Middle Aged ; Mutation ; Polycythemia Vera/genetics ; Primary Myelofibrosis/genetics ; Proto-Oncogene Proteins/genetics ; Repressor Proteins/genetics ; Thrombocythemia, Essential/genetics
    Chemical Substances ASXL1 protein, human ; DNA-Binding Proteins ; Proto-Oncogene Proteins ; Repressor Proteins ; Decitabine (776B62CQ27) ; Dioxygenases (EC 1.13.11.-) ; TET2 protein, human (EC 1.13.11.-) ; JAK2 protein, human (EC 2.7.10.2) ; Janus Kinase 2 (EC 2.7.10.2) ; Azacitidine (M801H13NRU)
    Language English
    Publishing date 2012-10-11
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 1432-1
    ISSN 1538-7445 ; 0008-5472
    ISSN (online) 1538-7445
    ISSN 0008-5472
    DOI 10.1158/0008-5472.CAN-12-0735
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: High resolution methylome analysis reveals widespread functional hypomethylation during adult human erythropoiesis.

    Yu, Yiting / Mo, Yongkai / Ebenezer, David / Bhattacharyya, Sanchari / Liu, Hui / Sundaravel, Sriram / Giricz, Orsolya / Wontakal, Sandeep / Cartier, Jessy / Caces, Bennett / Artz, Andrew / Nischal, Sangeeta / Bhagat, Tushar / Bathon, Kathleen / Maqbool, Shahina / Gligich, Oleg / Suzuki, Masako / Steidl, Ulrich / Godley, Lucy /
    Skoultchi, Art / Greally, John / Wickrema, Amittha / Verma, Amit

    The Journal of biological chemistry

    2013  Volume 288, Issue 13, Page(s) 8805–8814

    Abstract: Differentiation of hematopoietic stem cells to red cells requires coordinated expression of numerous erythroid genes and is characterized by nuclear condensation and extrusion during terminal development. To understand the regulatory mechanisms governing ...

    Abstract Differentiation of hematopoietic stem cells to red cells requires coordinated expression of numerous erythroid genes and is characterized by nuclear condensation and extrusion during terminal development. To understand the regulatory mechanisms governing these widespread phenotypic changes, we conducted a high resolution methylomic and transcriptomic analysis of six major stages of human erythroid differentiation. We observed widespread epigenetic differences between early and late stages of erythropoiesis with progressive loss of methylation being the dominant change during differentiation. Gene bodies, intergenic regions, and CpG shores were preferentially demethylated during erythropoiesis. Epigenetic changes at transcription factor binding sites correlated significantly with changes in gene expression and were enriched for binding motifs for SCL, MYB, GATA, and other factors not previously implicated in erythropoiesis. Demethylation at gene promoters was associated with increased expression of genes, whereas epigenetic changes at gene bodies correlated inversely with gene expression. Important gene networks encoding erythrocyte membrane proteins, surface receptors, and heme synthesis proteins were found to be regulated by DNA methylation. Furthermore, integrative analysis enabled us to identify novel, potential regulatory areas of the genome as evident by epigenetic changes in a predicted PU.1 binding site in intron 1 of the GATA1 gene. This intronic site was found to be conserved across species and was validated to be a novel PU.1 binding site by quantitative ChIP in erythroid cells. Altogether, our study provides a comprehensive analysis of methylomic and transcriptomic changes during erythroid differentiation and demonstrates that human terminal erythropoiesis is surprisingly associated with hypomethylation of the genome.
    MeSH term(s) Antigens, CD34/biosynthesis ; Binding Sites ; Cell Differentiation ; CpG Islands ; DNA Methylation ; Epigenesis, Genetic ; Epigenomics ; Erythrocytes/cytology ; Erythropoiesis/physiology ; Flow Cytometry/methods ; Gene Expression Profiling ; Gene Expression Regulation ; Genome, Human ; Genomics ; Humans ; Introns ; Methylation ; Oligonucleotide Array Sequence Analysis ; Stem Cells/chemistry
    Chemical Substances Antigens, CD34
    Language English
    Publishing date 2013-01-10
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    DOI 10.1074/jbc.M112.423756
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Myeloma is characterized by stage-specific alterations in DNA methylation that occur early during myelomagenesis.

    Heuck, Christoph J / Mehta, Jayesh / Bhagat, Tushar / Gundabolu, Krishna / Yu, Yiting / Khan, Shahper / Chrysofakis, Grigoris / Schinke, Carolina / Tariman, Joseph / Vickrey, Eric / Pulliam, Natalie / Nischal, Sangeeta / Zhou, Li / Bhattacharyya, Sanchari / Meagher, Richard / Hu, Caroline / Maqbool, Shahina / Suzuki, Masako / Parekh, Samir /
    Reu, Frederic / Steidl, Ulrich / Greally, John / Verma, Amit / Singhal, Seema B

    Journal of immunology (Baltimore, Md. : 1950)

    2013  Volume 190, Issue 6, Page(s) 2966–2975

    Abstract: Epigenetic changes play important roles in carcinogenesis and influence initial steps in neoplastic transformation by altering genome stability and regulating gene expression. To characterize epigenomic changes during the transformation of normal plasma ... ...

    Abstract Epigenetic changes play important roles in carcinogenesis and influence initial steps in neoplastic transformation by altering genome stability and regulating gene expression. To characterize epigenomic changes during the transformation of normal plasma cells to myeloma, we modified the HpaII tiny fragment enrichment by ligation-mediated PCR assay to work with small numbers of purified primary marrow plasma cells. The nano-HpaII tiny fragment enrichment by ligation-mediated PCR assay was used to analyze the methylome of CD138(+) cells from 56 subjects representing premalignant (monoclonal gammopathy of uncertain significance), early, and advanced stages of myeloma, as well as healthy controls. Plasma cells from premalignant and early stages of myeloma were characterized by striking, widespread hypomethylation. Gene-specific hypermethylation was seen to occur in the advanced stages, and cell lines representative of relapsed cases were found to be sensitive to decitabine. Aberrant demethylation in monoclonal gammopathy of uncertain significance occurred primarily in CpG islands, whereas differentially methylated loci in cases of myeloma occurred predominantly outside of CpG islands and affected distinct sets of gene pathways, demonstrating qualitative epigenetic differences between premalignant and malignant stages. Examination of the methylation machinery revealed that the methyltransferase, DNMT3A, was aberrantly hypermethylated and underexpressed, but not mutated in myeloma. DNMT3A underexpression was also associated with adverse overall survival in a large cohort of patients, providing insights into genesis of hypomethylation in myeloma. These results demonstrate widespread, stage-specific epigenetic changes during myelomagenesis and suggest that early demethylation can be a potential contributor to genome instability seen in myeloma. We also identify DNMT3A expression as a novel prognostic biomarker and suggest that relapsed cases can be therapeutically targeted by hypomethylating agents.
    MeSH term(s) Cell Transformation, Neoplastic/genetics ; Cell Transformation, Neoplastic/immunology ; Cohort Studies ; DNA Methylation/genetics ; DNA Methylation/immunology ; Early Diagnosis ; Gene Expression Regulation, Neoplastic/immunology ; Humans ; Multiple Myeloma/genetics ; Multiple Myeloma/immunology ; Multiple Myeloma/pathology ; Neoplasm Staging ; Polymerase Chain Reaction ; Recurrence ; Remission Induction ; Reproducibility of Results ; Syndecan-1/biosynthesis ; Syndecan-1/genetics ; Tumor Cells, Cultured
    Chemical Substances SDC1 protein, human ; Syndecan-1
    Language English
    Publishing date 2013-02-13
    Publishing country United States
    Document type Journal Article ; Randomized Controlled Trial ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 3056-9
    ISSN 1550-6606 ; 0022-1767 ; 1048-3233 ; 1047-7381
    ISSN (online) 1550-6606
    ISSN 0022-1767 ; 1048-3233 ; 1047-7381
    DOI 10.4049/jimmunol.1202493
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Aberrant epigenetic and genetic marks are seen in myelodysplastic leukocytes and reveal Dock4 as a candidate pathogenic gene on chromosome 7q.

    Zhou, Li / Opalinska, Joanna / Sohal, Davendra / Yu, Yiting / Mo, Yongkai / Bhagat, Tushar / Abdel-Wahab, Omar / Fazzari, Melissa / Figueroa, Maria / Alencar, Cristina / Zhang, Jinghang / Kambhampati, Suman / Parmar, Simrit / Nischal, Sangeeta / Hueck, Christoph / Suzuki, Masako / Freidman, Ellen / Pellagatti, Andrea / Boultwood, Jacqueline /
    Steidl, Ulrich / Sauthararajah, Yogen / Yajnik, Vijay / McMahon, Christine / Gore, Steven D / Platanias, Leonidas C / Levine, Ross / Melnick, Ari / Wickrema, Amittha / Greally, John M / Verma, Amit

    The Journal of biological chemistry

    2011  Volume 286, Issue 28, Page(s) 25211–25223

    Abstract: Myelodysplastic syndromes (MDS) are characterized by abnormal and dysplastic maturation of all blood lineages. Even though epigenetic alterations have been seen in MDS marrow progenitors, very little is known about the molecular alterations in dysplastic ...

    Abstract Myelodysplastic syndromes (MDS) are characterized by abnormal and dysplastic maturation of all blood lineages. Even though epigenetic alterations have been seen in MDS marrow progenitors, very little is known about the molecular alterations in dysplastic peripheral blood cells. We analyzed the methylome of MDS leukocytes by the HELP assay and determined that it was globally distinct from age-matched controls and was characterized by numerous novel, aberrant hypermethylated marks that were located mainly outside of CpG islands and preferentially affected GTPase regulators and other cancer-related pathways. Additionally, array comparative genomic hybridization revealed that novel as well as previously characterized deletions and amplifications could also be visualized in peripheral blood leukocytes, thus potentially reducing the need for bone marrow samples for future studies. Using integrative analysis, potentially pathogenic genes silenced by genetic deletions and aberrant hypermethylation in different patients were identified. DOCK4, a GTPase regulator located in the commonly deleted 7q31 region, was identified by this unbiased approach. Significant hypermethylation and reduced expression of DOCK4 in MDS bone marrow stem cells was observed in two large independent datasets, providing further validation of our findings. Finally, DOCK4 knockdown in primary marrow CD34(+) stem cells led to decreased erythroid colony formation and increased apoptosis, thus recapitulating the bone marrow failure seen in MDS. These findings reveal widespread novel epigenetic alterations in myelodysplastic leukocytes and implicate DOCK4 as a pathogenic gene located on the 7q chromosomal region.
    MeSH term(s) Apoptosis/genetics ; Bone Marrow Cells/metabolism ; Bone Marrow Cells/pathology ; Chromosome Deletion ; Chromosomes, Human, Pair 7/genetics ; Chromosomes, Human, Pair 7/metabolism ; CpG Islands/genetics ; DNA Methylation/genetics ; Epigenesis, Genetic ; Female ; GTPase-Activating Proteins/biosynthesis ; GTPase-Activating Proteins/genetics ; Genetic Markers ; Humans ; Leukocytes/metabolism ; Leukocytes/pathology ; Male ; Myelodysplastic Syndromes/genetics ; Myelodysplastic Syndromes/metabolism ; Myelodysplastic Syndromes/pathology ; Stem Cells/metabolism ; Stem Cells/pathology
    Chemical Substances DOCK4 protein, human ; GTPase-Activating Proteins ; Genetic Markers
    Language English
    Publishing date 2011-04-30
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    DOI 10.1074/jbc.M111.235028
    Database MEDical Literature Analysis and Retrieval System OnLINE

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