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  1. Article: Epigenetic mechanisms of induced pluripotency.

    Gładych, Marta / Andrzejewska, Anastazja / Oleksiewicz, Urszula / Estécio, Marcos R H

    Contemporary oncology (Poznan, Poland)

    2015  Volume 19, Issue 1A, Page(s) A30–8

    Abstract: Reprogramming of somatic cells to induced pluripotent stem cells (iPSCs) requires profound alterations in the epigenetic landscape. During reprogramming, a change in chromatin structure resets the gene expression and stabilises self-renewal. ... ...

    Abstract Reprogramming of somatic cells to induced pluripotent stem cells (iPSCs) requires profound alterations in the epigenetic landscape. During reprogramming, a change in chromatin structure resets the gene expression and stabilises self-renewal. Reprogramming is a highly inefficient process, in part due to multiple epigenetic barriers. Although many epigenetic factors have already been shown to affect self-renewal and pluripotency in embryonic stem cells (ESCs), only a few of them have been examined in the context of dedifferentiation. In order to improve current protocols of iPSCs generation, it is essential to identify epigenetic drivers and blockages of somatic cell reprogramming.
    Language English
    Publishing date 2015-01-29
    Publishing country Poland
    Document type Journal Article ; Review
    ISSN 1428-2526
    ISSN 1428-2526
    DOI 10.5114/wo.2014.47135
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Dissecting DNA hypermethylation in cancer

    Estécio, Marcos R.H / Issa, Jean-Pierre J

    FEBS letters. 2011 July 7, v. 585, no. 13

    2011  

    Abstract: There is compelling evidence to support the importance of DNA methylation alterations in cancer development. Both losses and gains of DNA methylation are observed, thought to contribute pathophysiologically by inactivating tumor suppressor genes, ... ...

    Abstract There is compelling evidence to support the importance of DNA methylation alterations in cancer development. Both losses and gains of DNA methylation are observed, thought to contribute pathophysiologically by inactivating tumor suppressor genes, inducing chromosomal instability and ectopically activating gene expression. Lesser known are the causes of aberrant DNA methylation. Recent studies have pointed out that intrinsic gene susceptibility to DNA methylation, environmental factors and gene function all have an intertwined participation in this process. Overall, these data support a deterministic rather than a stochastic mechanism for de novo DNA methylation in cancer. In this review article, we discuss the technologies available to study DNA methylation and the endogenous and exogenous factors that influence the onset of de novo methylation in cancer.
    Keywords DNA ; DNA methylation ; environmental factors ; gene expression ; tumor suppressor genes
    Language English
    Dates of publication 2011-0707
    Size p. 2078-2086.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 212746-5
    ISSN 1873-3468 ; 0014-5793
    ISSN (online) 1873-3468
    ISSN 0014-5793
    DOI 10.1016/j.febslet.2010.12.001
    Database NAL-Catalogue (AGRICOLA)

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  3. Article ; Online: Dissecting DNA hypermethylation in cancer.

    Estécio, Marcos R H / Issa, Jean-Pierre J

    FEBS letters

    2010  Volume 585, Issue 13, Page(s) 2078–2086

    Abstract: There is compelling evidence to support the importance of DNA methylation alterations in cancer development. Both losses and gains of DNA methylation are observed, thought to contribute pathophysiologically by inactivating tumor suppressor genes, ... ...

    Abstract There is compelling evidence to support the importance of DNA methylation alterations in cancer development. Both losses and gains of DNA methylation are observed, thought to contribute pathophysiologically by inactivating tumor suppressor genes, inducing chromosomal instability and ectopically activating gene expression. Lesser known are the causes of aberrant DNA methylation. Recent studies have pointed out that intrinsic gene susceptibility to DNA methylation, environmental factors and gene function all have an intertwined participation in this process. Overall, these data support a deterministic rather than a stochastic mechanism for de novo DNA methylation in cancer. In this review article, we discuss the technologies available to study DNA methylation and the endogenous and exogenous factors that influence the onset of de novo methylation in cancer.
    MeSH term(s) Animals ; DNA Methylation/genetics ; Humans ; Neoplasms/genetics
    Language English
    Publishing date 2010-12-10
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Review
    ZDB-ID 212746-5
    ISSN 1873-3468 ; 0014-5793
    ISSN (online) 1873-3468
    ISSN 0014-5793
    DOI 10.1016/j.febslet.2010.12.001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Cigarette smoke exposure accelerates AML progression in FLT3-ITD models.

    Figueroa, Mary / Ma, Huaxian / Alfayez, Mansour / Morales-Mantilla, Daniel Enrique / Wang, Fei / Lu, Yue / Estecio, Marcos R / King, Katherine Y / Kleinerman, Eugenie / Moghaddam, Seyed Javad / Daver, Naval / Andreeff, Michael / Konopleva, Marina / DiNardo, Courtney / Chandra, Joya

    Blood advances

    2023  Volume 7, Issue 21, Page(s) 6624–6629

    MeSH term(s) Humans ; Cigarette Smoking/adverse effects ; Leukemia, Myeloid, Acute/etiology ; Mutation ; fms-Like Tyrosine Kinase 3/genetics
    Chemical Substances fms-Like Tyrosine Kinase 3 (EC 2.7.10.1) ; FLT3 protein, human (EC 2.7.10.1)
    Language English
    Publishing date 2023-07-24
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 2915908-8
    ISSN 2473-9537 ; 2473-9529
    ISSN (online) 2473-9537
    ISSN 2473-9529
    DOI 10.1182/bloodadvances.2023010111
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: SINE retrotransposons cause epigenetic reprogramming of adjacent gene promoters.

    Estécio, Marcos R H / Gallegos, Juan / Dekmezian, Mhair / Lu, Yue / Liang, Shoudan / Issa, Jean-Pierre J

    Molecular cancer research : MCR

    2012  Volume 10, Issue 10, Page(s) 1332–1342

    Abstract: ... loss of activating histone marks, thus resulting in a repressed state. SINE sequences themselves did ... not immediately acquire DNA methylation but were marked by H3K9me2 and H3K27me3. Moreover ...

    Abstract Almost half of the human genome and as much as 40% of the mouse genome is composed of repetitive DNA sequences. The majority of these repeats are retrotransposons of the SINE and LINE families, and such repeats are generally repressed by epigenetic mechanisms. It has been proposed that these elements can act as methylation centers from which DNA methylation spreads into gene promoters in cancer. Contradictory to a methylation center function, we have found that retrotransposons are enriched near promoter CpG islands that stay methylation-free in cancer. Clearly, it is important to determine which influence, if any, these repetitive elements have on nearby gene promoters. Using an in vitro system, we confirm here that SINE B1 elements can influence the activity of downstream gene promoters, with acquisition of DNA methylation and loss of activating histone marks, thus resulting in a repressed state. SINE sequences themselves did not immediately acquire DNA methylation but were marked by H3K9me2 and H3K27me3. Moreover, our bisulfite sequencing data did not support that gain of DNA methylation in gene promoters occurred by methylation spreading from SINE B1 repeats. Genome-wide analysis of SINE repeats distribution showed that their enrichment is directly correlated with the presence of USF1, USF2, and CTCF binding, proteins with insulator function. In summary, our work supports the concept that SINE repeats interfere negatively with gene expression and that their presence near gene promoters is counter-selected, except when the promoter is protected by an insulator element.
    MeSH term(s) Adaptor Proteins, Signal Transducing/genetics ; Alu Elements/genetics ; Animals ; Antigens, CD ; Cadherins/genetics ; Cellular Reprogramming/genetics ; Chromatin/metabolism ; Cyclin-Dependent Kinase Inhibitor p19/genetics ; DNA Methylation/genetics ; Epigenesis, Genetic ; Gene Silencing ; Genes/genetics ; Humans ; Insulator Elements/genetics ; Long Interspersed Nucleotide Elements/genetics ; Mice ; MutL Protein Homolog 1 ; NIH 3T3 Cells ; Nuclear Proteins/genetics ; Promoter Regions, Genetic ; Protein Binding/genetics ; Short Interspersed Nucleotide Elements/genetics ; Transcription Initiation Site ; Transcription, Genetic ; Tumor Suppressor Protein p14ARF/genetics
    Chemical Substances Adaptor Proteins, Signal Transducing ; Antigens, CD ; CDH1 protein, human ; Cadherins ; Cdkn2d protein, mouse ; Chromatin ; Cyclin-Dependent Kinase Inhibitor p19 ; Mlh1 protein, mouse ; Nuclear Proteins ; Tumor Suppressor Protein p14ARF ; MutL Protein Homolog 1 (EC 3.6.1.3)
    Language English
    Publishing date 2012-09-04
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2098788-2
    ISSN 1557-3125 ; 1541-7786
    ISSN (online) 1557-3125
    ISSN 1541-7786
    DOI 10.1158/1541-7786.MCR-12-0351
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Single-cell multimodal glioma analyses identify epigenetic regulators of cellular plasticity and environmental stress response.

    Johnson, Kevin C / Anderson, Kevin J / Courtois, Elise T / Gujar, Amit D / Barthel, Floris P / Varn, Frederick S / Luo, Diane / Seignon, Martine / Yi, Eunhee / Kim, Hoon / Estecio, Marcos R H / Zhao, Dacheng / Tang, Ming / Navin, Nicholas E / Maurya, Rahul / Ngan, Chew Yee / Verburg, Niels / de Witt Hamer, Philip C / Bulsara, Ketan /
    Samuels, Michael L / Das, Sunit / Robson, Paul / Verhaak, Roel G W

    Nature genetics

    2021  Volume 53, Issue 10, Page(s) 1456–1468

    Abstract: Glioma intratumoral heterogeneity enables adaptation to challenging microenvironments and contributes to therapeutic resistance. We integrated 914 single-cell DNA methylomes, 55,284 single-cell transcriptomes and bulk multi-omic profiles across 11 adult ... ...

    Abstract Glioma intratumoral heterogeneity enables adaptation to challenging microenvironments and contributes to therapeutic resistance. We integrated 914 single-cell DNA methylomes, 55,284 single-cell transcriptomes and bulk multi-omic profiles across 11 adult IDH mutant or IDH wild-type gliomas to delineate sources of intratumoral heterogeneity. We showed that local DNA methylation disorder is associated with cell-cell DNA methylation differences, is elevated in more aggressive tumors, links with transcriptional disruption and is altered during the environmental stress response. Glioma cells under in vitro hypoxic and irradiation stress increased local DNA methylation disorder and shifted cell states. We identified a positive association between genetic and epigenetic instability that was supported in bulk longitudinally collected DNA methylation data. Increased DNA methylation disorder associated with accelerated disease progression and recurrently selected DNA methylation changes were enriched for environmental stress response pathways. Our work identified an epigenetically facilitated adaptive stress response process and highlights the importance of epigenetic heterogeneity in shaping therapeutic outcomes.
    MeSH term(s) Brain Neoplasms/genetics ; Cell Plasticity/genetics ; Clonal Evolution ; DNA Copy Number Variations/genetics ; DNA Methylation/genetics ; Epigenesis, Genetic ; Gene Expression Regulation, Neoplastic ; Genetic Heterogeneity ; Genome, Human ; Glioma/genetics ; Humans ; Mutation/genetics ; Phylogeny ; Promoter Regions, Genetic/genetics ; Single-Cell Analysis ; Stress, Physiological/genetics ; Tumor Microenvironment/genetics
    Language English
    Publishing date 2021-09-30
    Publishing country United States
    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 1108734-1
    ISSN 1546-1718 ; 1061-4036
    ISSN (online) 1546-1718
    ISSN 1061-4036
    DOI 10.1038/s41588-021-00926-8
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Differentially methylated genes and androgen receptor re-expression in small cell prostate carcinomas.

    Kleb, Brittany / Estécio, Marcos R H / Zhang, Jiexin / Tzelepi, Vassiliki / Chung, Woonbok / Jelinek, Jaroslav / Navone, Nora M / Tahir, Salahaldin / Marquez, Victor E / Issa, Jean-Pierre / Maity, Sankar / Aparicio, Ana

    Epigenetics

    2016  Volume 11, Issue 3, Page(s) 184–193

    Abstract: Small cell prostate carcinoma (SCPC) morphology is rare at initial diagnosis but often emerges during prostate cancer progression and portends a dismal prognosis. It does not express androgen receptor (AR) or respond to hormonal therapies. Clinically ... ...

    Abstract Small cell prostate carcinoma (SCPC) morphology is rare at initial diagnosis but often emerges during prostate cancer progression and portends a dismal prognosis. It does not express androgen receptor (AR) or respond to hormonal therapies. Clinically applicable markers for its early detection and treatment with effective chemotherapy are needed. Our studies in patient tumor-derived xenografts (PDX) revealed that AR-negative SCPC (AR(-)SCPC) expresses neural development genes instead of the prostate luminal epithelial genes characteristic of AR-positive castration-resistant adenocarcinomas (AR(+)ADENO). We hypothesized that the differences in cellular lineage programs are reflected in distinct epigenetic profiles. To address this hypothesis, we compared the DNA methylation profiles of AR(-) and AR(+) PDX using methylated CpG island amplification and microarray (MCAM) analysis and identified a set of differentially methylated promoters, validated in PDX and corresponding donor patient samples. We used the Illumina 450K platform to examine additional regions of the genome and the correlation between the DNA methylation profiles of the PDX and their corresponding patient tumors. Struck by the low frequency of AR promoter methylation in the AR(-)SCPC, we investigated this region's specific histone modification patterns by chromatin immunoprecipitation. We found that the AR promoter was enriched in silencing histone modifications (H3K27me3 and H3K9me2) and that EZH2 inhibition with 3-deazaneplanocin A (DZNep) resulted in AR expression and growth inhibition in AR(-)SCPC cell lines. We conclude that the epigenome of AR(-) is distinct from that of AR(+) castration-resistant prostate carcinomas, and that the AR(-) phenotype can be reversed with epigenetic drugs.
    MeSH term(s) Adenosine/administration & dosage ; Adenosine/analogs & derivatives ; Animals ; Carcinoma, Small Cell/genetics ; Carcinoma, Small Cell/pathology ; Cell Line, Tumor ; Cell Lineage/genetics ; CpG Islands/genetics ; DNA Methylation/genetics ; Enhancer of Zeste Homolog 2 Protein/antagonists & inhibitors ; Enhancer of Zeste Homolog 2 Protein/genetics ; Gene Expression Regulation, Neoplastic/drug effects ; Humans ; Male ; Mice ; Promoter Regions, Genetic ; Prostatic Neoplasms, Castration-Resistant/genetics ; Prostatic Neoplasms, Castration-Resistant/pathology ; Receptors, Androgen/biosynthesis ; Receptors, Androgen/genetics ; Xenograft Model Antitumor Assays
    Chemical Substances Receptors, Androgen ; 3-deazaneplanocin (544SH4020S) ; EZH2 protein, human (EC 2.1.1.43) ; Enhancer of Zeste Homolog 2 Protein (EC 2.1.1.43) ; Adenosine (K72T3FS567)
    Language English
    Publishing date 2016-03-03
    Publishing country United States
    Document type Journal Article
    ISSN 1559-2308
    ISSN (online) 1559-2308
    DOI 10.1080/15592294.2016.1146851
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Transcriptomic Signatures of Hypomethylating Agent Failure in Myelodysplastic Syndromes and Chronic Myelomonocytic Leukemia.

    Darbaniyan, Faezeh / Zheng, Hong / Kanagal-Shamanna, Rashmi / Lockyer, Pamela / Montalban-Bravo, Guillermo / Estecio, Marcos / Lu, Yue / Soltysiak, Kelly A / Chien, Kelly S / Yang, Hui / Sasaki, Koji / Class, Caleb / Ganan-Gomez, Irene / Do, Kim-Anh / Garcia-Manero, Guillermo / Wei, Yue

    Experimental hematology

    2022  Volume 115, Page(s) 44–53

    Abstract: Hypomethylating agents (HMAs) are the standard of care for myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML). HMA treatment failure is a major clinical problem and its mechanisms are poorly characterized. We performed RNA ... ...

    Abstract Hypomethylating agents (HMAs) are the standard of care for myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML). HMA treatment failure is a major clinical problem and its mechanisms are poorly characterized. We performed RNA sequencing in CD34
    MeSH term(s) Humans ; Mice ; Animals ; Leukemia, Myelomonocytic, Chronic/drug therapy ; Leukemia, Myelomonocytic, Chronic/genetics ; Transcriptome ; Myelodysplastic Syndromes/drug therapy ; Myelodysplastic Syndromes/genetics ; Myelodysplastic Syndromes/metabolism ; Azacitidine/pharmacology ; Azacitidine/therapeutic use ; Leukemia, Myelomonocytic, Juvenile/drug therapy
    Chemical Substances Azacitidine (M801H13NRU)
    Language English
    Publishing date 2022-09-21
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 185107-x
    ISSN 1873-2399 ; 0531-5573 ; 0301-472X
    ISSN (online) 1873-2399
    ISSN 0531-5573 ; 0301-472X
    DOI 10.1016/j.exphem.2022.09.002
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Myotonic dystrophy type 1 (DM1) clinical subtypes and CTCF site methylation status flanking the CTG expansion are mutant allele length-dependent.

    Morales, Fernando / Corrales, Eyleen / Zhang, Baili / Vásquez, Melissa / Santamaría-Ulloa, Carolina / Quesada, Hazel / Sirito, Mario / Estecio, Marcos R / Monckton, Darren G / Krahe, Ralf

    Human molecular genetics

    2021  Volume 31, Issue 2, Page(s) 262–274

    Abstract: Myotonic dystrophy type 1 (DM1) is a complex disease with a wide spectrum of symptoms. The exact relationship between mutant CTG repeat expansion size and clinical outcome remains unclear. DM1 congenital patients (CDM) inherit the largest expanded ... ...

    Abstract Myotonic dystrophy type 1 (DM1) is a complex disease with a wide spectrum of symptoms. The exact relationship between mutant CTG repeat expansion size and clinical outcome remains unclear. DM1 congenital patients (CDM) inherit the largest expanded alleles, which are associated with abnormal and increased DNA methylation flanking the CTG repeat. However, DNA methylation at the DMPK locus remains understudied. Its relationship to DM1 clinical subtypes, expansion size and age-at-onset is not yet completely understood. Using pyrosequencing-based methylation analysis on 225 blood DNA samples from Costa Rican DM1 patients, we determined that the size of the estimated progenitor allele length (ePAL) is not only a good discriminator between CDM and non-CDM cases (with an estimated threshold at 653 CTG repeats), but also for all DM1 clinical subtypes. Secondly, increased methylation at both CTCF sites upstream and downstream of the expansion was almost exclusively present in CDM cases. Thirdly, levels of abnormal methylation were associated with clinical subtype, age and ePAL, with strong correlations between these variables. Fourthly, both ePAL and the intergenerational expansion size were significantly associated with methylation status. Finally, methylation status was associated with ePAL and maternal inheritance, with almost exclusively maternal transmission of CDM. In conclusion, increased DNA methylation at the CTCF sites flanking the DM1 expansion could be linked to ePAL, and both increased methylation and the ePAL could be considered biomarkers for the CDM phenotype.
    MeSH term(s) Alleles ; CCCTC-Binding Factor ; DNA Methylation/genetics ; Humans ; Myotonic Dystrophy/genetics ; Myotonin-Protein Kinase/genetics ; Trinucleotide Repeat Expansion/genetics
    Chemical Substances CCCTC-Binding Factor ; CTCF protein, human ; Myotonin-Protein Kinase (EC 2.7.11.1)
    Language English
    Publishing date 2021-08-25
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 1108742-0
    ISSN 1460-2083 ; 0964-6906
    ISSN (online) 1460-2083
    ISSN 0964-6906
    DOI 10.1093/hmg/ddab243
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Methylated CpG Island Amplification and Microarray (MCAM) for High-Throughput Analysis of DNA Methylation.

    Estécio, Marcos R H / Yan, Pearlly S / Huang, Tim H-M / Issa, Jean-Pierre J

    CSH protocols

    2008  Volume 2008, Page(s) pdb.prot4974

    Abstract: INTRODUCTIONThis protocol describes the use of methylated CpG island amplification (MCA) in combination with a microarray platform to analyze genome-wide DNA methylation in a high-throughput fashion. In this approach, termed MCAM, methylated CpG islands ... ...

    Abstract INTRODUCTIONThis protocol describes the use of methylated CpG island amplification (MCA) in combination with a microarray platform to analyze genome-wide DNA methylation in a high-throughput fashion. In this approach, termed MCAM, methylated CpG islands are selectively targeted using oligonucleotide adaptors after two rounds of digestion with a combination of methylation-sensitive and methylation-insensitive nucleases. They are then amplified using PCR. The resulting amplicons, representing the methylated fraction of the genome, are labeled with fluorochromes. Subsequently, a comparative hybridization of reference and test samples (typically normal and tumor DNA specimens) is done on a microarray platform.
    Language English
    Publishing date 2008-03-01
    Publishing country United States
    Document type Journal Article
    DOI 10.1101/pdb.prot4974
    Database MEDical Literature Analysis and Retrieval System OnLINE

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