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1.
Case Rep Psychiatry ; 2022: 8162871, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35620411

RESUMEN

Our patient Mr. A is a mentally and physically disabled gentleman. He was first diagnosed with bipolar disorder as a teenager. He incurred a lumbar spinal injury due to a motor vehicle incident in his 20s which led to weakness, numbness, and frequent infection over both of his lower extremities. He also developed alcohol addiction over the course of his life. Mr. A presented to our facility with complicated neuropsychiatric symptoms. By adopting various clinical strategies, we were able to control his symptoms of agitation, self-harm, mood swings, and stereotyped behavior. However, we were not able to improve his neurocognitive functioning or speech impairment which seemed to become severe and irreversible in a period of a few months. We felt disappointed and perplexed by the mixed treatment responses. To understand Mr. A's clinical presentation, various laboratory tests and imaging studies were performed. Different psychotropic medications were used to manage his symptoms. Gradually, we felt that we were able to understand this case better clinically and etiologically. His bipolar disorder, alcohol addiction, and physical injury had likely all contributed to his neuropsychiatric symptoms, directly or indirectly. It is highly possible that an alcohol-related progressive dementia along with his chronic bipolar disorder played a key role in the progression of his brain neurodegeneration. Also, Wernicke-Korsakoff syndrome could reasonably be considered having developed during his clinical course. Moreover, the fluctuation of the patient's neuropsychiatric symptoms we observed during his hospitalization reflects the increased vulnerability of the human brain under sustained neurodegeneration.

2.
Leukemia ; 35(7): 2002-2016, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33953289

RESUMEN

B cells have the unique property to somatically alter their immunoglobulin (IG) genes by V(D)J recombination, somatic hypermutation (SHM) and class-switch recombination (CSR). Aberrant targeting of these mechanisms is implicated in lymphomagenesis, but the mutational processes are poorly understood. By performing whole genome and transcriptome sequencing of 181 germinal center derived B-cell lymphomas (gcBCL) we identified distinct mutational signatures linked to SHM and CSR. We show that not only SHM, but presumably also CSR causes off-target mutations in non-IG genes. Kataegis clusters with high mutational density mainly affected early replicating regions and were enriched for SHM- and CSR-mediated off-target mutations. Moreover, they often co-occurred in loci physically interacting in the nucleus, suggesting that mutation hotspots promote increased mutation targeting of spatially co-localized loci (termed hypermutation by proxy). Only around 1% of somatic small variants were in protein coding sequences, but in about half of the driver genes, a contribution of B-cell specific mutational processes to their mutations was found. The B-cell-specific mutational processes contribute to both lymphoma initiation and intratumoral heterogeneity. Overall, we demonstrate that mutational processes involved in the development of gcBCL are more complex than previously appreciated, and that B cell-specific mutational processes contribute via diverse mechanisms to lymphomagenesis.


Asunto(s)
Genoma/genética , Centro Germinal/metabolismo , Linfoma de Células B/genética , Mutación/genética , Adulto , Linfocitos B/metabolismo , Línea Celular , Línea Celular Tumoral , Genes de Inmunoglobulinas/genética , Células HeLa , Células Hep G2 , Células Endoteliales de la Vena Umbilical Humana , Humanos , Cambio de Clase de Inmunoglobulina/genética , Células K562 , Células MCF-7 , Hipermutación Somática de Inmunoglobulina/genética , Recombinación V(D)J/genética
3.
Expert Opin Drug Saf ; 19(2): 147-157, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31976781

RESUMEN

Introduction: Alzheimer's disease (AD) is the most common cause of major neurocognitive disorders with a prevalence in the US of about 5.7 million in 2018. With the disease burden projected to increase dramatically in the coming years, it is imperative to review the current available treatment regimens for their safety and utility. The cholinesterase inhibitors (ChEIs) have continued to play a pivotal role in managing the symptoms and possibly slowing the rate of progression of AD since 1993. Owing to their being a mainstay in the treatment of AD, the safety and efficacy of prescribing these drugs needs to be reviewed often, especially with the approval of new formulations and doses.Areas covered: The three ChEIs currently approved by the FDA are donepezil, rivastigmine and galantamine. This article will review the safety and tolerability of these ChEIs and analyze the potential disease modifying properties of these drugs. The authors have reviewed all recent literature including review articles, meta-analyzes, clinical trials and more.Expert opinion: These ChEIs differ subtly in their mechanisms of action, in their tolerability and safety and FDA-approved indications. All are considered first-line, symptomatic treatments of the various phases of AD and may even have potentially disease-modifying effects.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/administración & dosificación , Enfermedad de Alzheimer/fisiopatología , Animales , Inhibidores de la Colinesterasa/efectos adversos , Donepezilo/administración & dosificación , Donepezilo/efectos adversos , Galantamina/administración & dosificación , Galantamina/efectos adversos , Humanos , Rivastigmina/administración & dosificación , Rivastigmina/efectos adversos
4.
Genome Med ; 11(1): 27, 2019 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-31039827

RESUMEN

BACKGROUND: Germinal center-derived B cell lymphomas are tumors of the lymphoid tissues representing one of the most heterogeneous malignancies. Here we characterize the variety of transcriptomic phenotypes of this disease based on 873 biopsy specimens collected in the German Cancer Aid MMML (Molecular Mechanisms in Malignant Lymphoma) consortium. They include diffuse large B cell lymphoma (DLBCL), follicular lymphoma (FL), Burkitt's lymphoma, mixed FL/DLBCL lymphomas, primary mediastinal large B cell lymphoma, multiple myeloma, IRF4-rearranged large cell lymphoma, MYC-negative Burkitt-like lymphoma with chr. 11q aberration and mantle cell lymphoma. METHODS: We apply self-organizing map (SOM) machine learning to microarray-derived expression data to generate a holistic view on the transcriptome landscape of lymphomas, to describe the multidimensional nature of gene regulation and to pursue a modular view on co-expression. Expression data were complemented by pathological, genetic and clinical characteristics. RESULTS: We present a transcriptome map of B cell lymphomas that allows visual comparison between the SOM portraits of different lymphoma strata and individual cases. It decomposes into one dozen modules of co-expressed genes related to different functional categories, to genetic defects and to the pathogenesis of lymphomas. On a molecular level, this disease rather forms a continuum of expression states than clearly separated phenotypes. We introduced the concept of combinatorial pattern types (PATs) that stratifies the lymphomas into nine PAT groups and, on a coarser level, into five prominent cancer hallmark types with proliferation, inflammation and stroma signatures. Inflammation signatures in combination with healthy B cell and tonsil characteristics associate with better overall survival rates, while proliferation in combination with inflammation and plasma cell characteristics worsens it. A phenotypic similarity tree is presented that reveals possible progression paths along the transcriptional dimensions. Our analysis provided a novel look on the transition range between FL and DLBCL, on DLBCL with poor prognosis showing expression patterns resembling that of Burkitt's lymphoma and particularly on 'double-hit' MYC and BCL2 transformed lymphomas. CONCLUSIONS: The transcriptome map provides a tool that aggregates, refines and visualizes the data collected in the MMML study and interprets them in the light of previous knowledge to provide orientation and support in current and future studies on lymphomas and on other cancer entities.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Linfoma de Células B/genética , Transcriptoma , Humanos , Linfoma de Células B/metabolismo , Linfoma de Células B/patología , Aprendizaje Automático
5.
Nat Commun ; 10(1): 1459, 2019 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-30926794

RESUMEN

Burkitt lymphoma (BL) is the most common B-cell lymphoma in children. Within the International Cancer Genome Consortium (ICGC), we performed whole genome and transcriptome sequencing of 39 sporadic BL. Here, we unravel interaction of structural, mutational, and transcriptional changes, which contribute to MYC oncogene dysregulation together with the pathognomonic IG-MYC translocation. Moreover, by mapping IGH translocation breakpoints, we provide evidence that the precursor of at least a subset of BL is a B-cell poised to express IGHA. We describe the landscape of mutations, structural variants, and mutational processes, and identified a series of driver genes in the pathogenesis of BL, which can be targeted by various mechanisms, including IG-non MYC translocations, germline and somatic mutations, fusion transcripts, and alternative splicing.


Asunto(s)
Linfoma de Burkitt/genética , Genoma Humano , Transcriptoma/genética , Adolescente , Empalme Alternativo/genética , Secuencia de Aminoácidos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/química , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Niño , Preescolar , Puntos de Rotura del Cromosoma , Estudios de Cohortes , Metilación de ADN/genética , Análisis Mutacional de ADN , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Mutación INDEL/genética , Masculino , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Sistemas de Lectura Abierta/genética , Polimorfismo de Nucleótido Simple/genética , Proteínas Proto-Oncogénicas c-myc/genética , Translocación Genética , Secuenciación Completa del Genoma
7.
Nature ; 546(7657): 302-306, 2017 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-28562582

RESUMEN

Similar to resting mature B cells, where the B-cell antigen receptor (BCR) controls cellular survival, surface BCR expression is conserved in most mature B-cell lymphomas. The identification of activating BCR mutations and the growth disadvantage upon BCR knockdown of cells of certain lymphoma entities has led to the view that BCR signalling is required for tumour cell survival. Consequently, the BCR signalling machinery has become an established target in the therapy of B-cell malignancies. Here we study the effects of BCR ablation on MYC-driven mouse B-cell lymphomas and compare them with observations in human Burkitt lymphoma. Whereas BCR ablation does not, per se, significantly affect lymphoma growth, BCR-negative (BCR-) tumour cells rapidly disappear in the presence of their BCR-expressing (BCR+) counterparts in vitro and in vivo. This requires neither cellular contact nor factors released by BCR+ tumour cells. Instead, BCR loss induces the rewiring of central carbon metabolism, increasing the sensitivity of receptor-less lymphoma cells to nutrient restriction. The BCR attenuates glycogen synthase kinase 3 beta (GSK3ß) activity to support MYC-controlled gene expression. BCR- tumour cells exhibit increased GSK3ß activity and are rescued from their competitive growth disadvantage by GSK3ß inhibition. BCR- lymphoma variants that restore competitive fitness normalize GSK3ß activity after constitutive activation of the MAPK pathway, commonly through Ras mutations. Similarly, in Burkitt lymphoma, activating RAS mutations may propagate immunoglobulin-crippled tumour cells, which usually represent a minority of the tumour bulk. Thus, while BCR expression enhances lymphoma cell fitness, BCR-targeted therapies may profit from combinations with drugs targeting BCR- tumour cells.


Asunto(s)
Linfocitos B/metabolismo , Genes myc , Aptitud Genética , Glucógeno Sintasa Quinasa 3 beta/antagonistas & inhibidores , Linfoma/genética , Linfoma/metabolismo , Receptores de Antígenos de Linfocitos B/metabolismo , Animales , Linfocitos B/inmunología , Linfocitos B/patología , Linfoma de Burkitt/genética , Linfoma de Burkitt/inmunología , Linfoma de Burkitt/patología , Carbono/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Genes ras/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , Linfoma/enzimología , Linfoma/patología , Sistema de Señalización de MAP Quinasas , Masculino , Ratones , Mutación , Receptores de Antígenos de Linfocitos B/deficiencia , Receptores de Antígenos de Linfocitos B/genética , Receptores de Antígenos de Linfocitos B/inmunología , Células Tumorales Cultivadas
8.
Haematologica ; 101(11): 1380-1389, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27390358

RESUMEN

MicroRNA are well-established players in post-transcriptional gene regulation. However, information on the effects of microRNA deregulation mainly relies on bioinformatic prediction of potential targets, whereas proof of the direct physical microRNA/target messenger RNA interaction is mostly lacking. Within the International Cancer Genome Consortium Project "Determining Molecular Mechanisms in Malignant Lymphoma by Sequencing", we performed miRnome sequencing from 16 Burkitt lymphomas, 19 diffuse large B-cell lymphomas, and 21 follicular lymphomas. Twenty-two miRNA separated Burkitt lymphomas from diffuse large B-cell lymphomas/follicular lymphomas, of which 13 have shown regulation by MYC. Moreover, we found expression of three hitherto unreported microRNA. Additionally, we detected recurrent mutations of hsa-miR-142 in diffuse large B-cell lymphomas and follicular lymphomas, and editing of the hsa-miR-376 cluster, providing evidence for microRNA editing in lymphomagenesis. To interrogate the direct physical interactions of microRNA with messenger RNA, we performed Argonaute-2 photoactivatable ribonucleoside-enhanced cross-linking and immunoprecipitation experiments. MicroRNA directly targeted 208 messsenger RNA in the Burkitt lymphomas and 328 messenger RNA in the non-Burkitt lymphoma models. This integrative analysis discovered several regulatory pathways of relevance in lymphomagenesis including Ras, PI3K-Akt and MAPK signaling pathways, also recurrently deregulated in lymphomas by mutations. Our dataset reveals that messenger RNA deregulation through microRNA is a highly relevant mechanism in lymphomagenesis.


Asunto(s)
Linfoma de Células B/genética , MicroARNs/metabolismo , ARN Mensajero/metabolismo , Análisis de Secuencia de ARN/métodos , Adolescente , Linfoma de Burkitt/genética , Niño , Preescolar , Femenino , Perfilación de la Expresión Génica , Centro Germinal , Humanos , Lactante , Recién Nacido , Linfoma Folicular/genética , Linfoma de Células B Grandes Difuso/genética , Masculino , MicroARNs/genética , Mutación , Edición de ARN
9.
Epigenomics ; 8(6): 801-16, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27323310

RESUMEN

AIM: To characterize the genotypic and phenotypic extent of multilocus imprinting disturbances (MLID). MATERIALS & METHODS: We analyzed 37 patients with imprinting disorders (explorative cohort) for DNA methylation changes using the Infinium HumanMethylation450 BeadChip. For validation, three independent cohorts with imprinting disorders or cardinal features thereof were analyzed (84 patients with imprinting disorders, 52 with growth disorder, 81 with developmental delay). RESULTS: In the explorative cohort 21 individuals showed array-based MLID with each one displaying an Angelman or Temple syndrome phenotype, respectively. Epimutations in ZDBF2 and FAM50B were associated with severe MLID regarding number of affected regions. By targeted analysis we identified methylation changes of ZDBF2 and FAM50B also in the three validation cohorts. CONCLUSION: We corroborate epimutations in ZDBF2 and FAM50B as frequent changes in MLID whereas these rarely occur in other patients with cardinal features of imprinting disorders. Moreover, we show cell lineage specific differences in the genomic extent of FAM50B epimutation.


Asunto(s)
Metilación de ADN , Discapacidades del Desarrollo/genética , Impresión Genómica , Estudios de Casos y Controles , Proteínas de Unión al ADN/genética , Femenino , Estudios de Asociación Genética , Humanos , Masculino , Fenotipo , Proteínas/genética , Análisis de Secuencia de ADN
11.
Methods Mol Biol ; 1381: 75-92, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26667456

RESUMEN

Epigenetic mechanisms including DNA methylation are fundamental for the regulation of gene expression. Epigenetic alterations can lead to the development and the evolution of malignant tumors as well as the emergence of phenotypically different cancer cells or metastasis from one single tumor cell. Here we describe bisulfite pyrosequencing, a technology to perform quantitative DNA methylation analyses, to detect aberrant DNA methylation in malignant tumors.


Asunto(s)
Dermatoglifia del ADN/métodos , Metilación de ADN , ADN/genética , Secuencia de Bases , ADN/análisis , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias/genética , Sulfitos/química
12.
Nat Genet ; 47(11): 1316-1325, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26437030

RESUMEN

Although Burkitt lymphomas and follicular lymphomas both have features of germinal center B cells, they are biologically and clinically quite distinct. Here we performed whole-genome bisulfite, genome and transcriptome sequencing in 13 IG-MYC translocation-positive Burkitt lymphoma, nine BCL2 translocation-positive follicular lymphoma and four normal germinal center B cell samples. Comparison of Burkitt and follicular lymphoma samples showed differential methylation of intragenic regions that strongly correlated with expression of associated genes, for example, genes active in germinal center dark-zone and light-zone B cells. Integrative pathway analyses of regions differentially methylated in Burkitt and follicular lymphomas implicated DNA methylation as cooperating with somatic mutation of sphingosine phosphate signaling, as well as the TCF3-ID3 and SWI/SNF complexes, in a large fraction of Burkitt lymphomas. Taken together, our results demonstrate a tight connection between somatic mutation, DNA methylation and transcriptional control in key B cell pathways deregulated differentially in Burkitt lymphoma and other germinal center B cell lymphomas.


Asunto(s)
Linfoma de Burkitt/genética , Metilación de ADN , Linfoma Folicular/genética , Mutación , Transcriptoma/genética , Adolescente , Adulto , Anciano , Linfocitos B/metabolismo , Línea Celular Tumoral , Niño , Preescolar , Femenino , Genoma Humano/genética , Centro Germinal/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Masculino , Persona de Mediana Edad , Proteínas de Fusión Oncogénica/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-myc/genética , Transducción de Señal/genética , Translocación Genética , Adulto Joven
13.
Proc Natl Acad Sci U S A ; 112(38): E5261-70, 2015 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-26351698

RESUMEN

Despite the established role of the transcription factor MYC in cancer, little is known about the impact of a new class of transcriptional regulators, the long noncoding RNAs (lncRNAs), on MYC ability to influence the cellular transcriptome. Here, we have intersected RNA-sequencing data from two MYC-inducible cell lines and a cohort of 91 B-cell lymphomas with or without genetic variants resulting in MYC overexpression. We identified 13 lncRNAs differentially expressed in IG-MYC-positive Burkitt lymphoma and regulated in the same direction by MYC in the model cell lines. Among them, we focused on a lncRNA that we named MYC-induced long noncoding RNA (MINCR), showing a strong correlation with MYC expression in MYC-positive lymphomas. To understand its cellular role, we performed RNAi and found that MINCR knockdown is associated with an impairment in cell cycle progression. Differential gene expression analysis after RNAi showed a significant enrichment of cell cycle genes among the genes down-regulated after MINCR knockdown. Interestingly, these genes are enriched in MYC binding sites in their promoters, suggesting that MINCR acts as a modulator of the MYC transcriptional program. Accordingly, MINCR knockdown was associated with a reduction in MYC binding to the promoters of selected cell cycle genes. Finally, we show that down-regulation of Aurora kinases A and B and chromatin licensing and DNA replication factor 1 may explain the reduction in cellular proliferation observed on MINCR knockdown. We, therefore, suggest that MINCR is a newly identified player in the MYC transcriptional network able to control the expression of cell cycle genes.


Asunto(s)
Linfoma de Burkitt/metabolismo , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Linfoma de Células B/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , ARN Largo no Codificante/metabolismo , Secuencia de Bases , Sitios de Unión , Ciclo Celular , Línea Celular , Línea Celular Tumoral , Supervivencia Celular , Cromatina/metabolismo , Perfilación de la Expresión Génica , Humanos , Hibridación Fluorescente in Situ , Datos de Secuencia Molecular , Neoplasias/metabolismo , Regiones Promotoras Genéticas , ARN Interferente Pequeño/metabolismo , Homología de Secuencia de Ácido Nucleico
14.
Genes Chromosomes Cancer ; 54(9): 555-64, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26173642

RESUMEN

The genetic hallmark of Burkitt lymphoma is the translocation t(8;14)(q24;q32), or one of its light chain variants, resulting in IG-MYC juxtaposition. However, these translocations alone are insufficient to drive lymphomagenesis, which requires additional genetic changes for malignant transformation. Recent studies of Burkitt lymphoma using next generation sequencing approaches have identified various recurrently mutated genes including ID3, TCF3, CCND3, and TP53. Here, by using similar approaches, we show that PCBP1 is a recurrently mutated gene in Burkitt lymphoma. By whole-genome sequencing, we identified somatic mutations in PCBP1 in 3/17 (18%) Burkitt lymphomas. We confirmed the recurrence of PCBP1 mutations by Sanger sequencing in an independent validation cohort, finding mutations in 3/28 (11%) Burkitt lymphomas and in 6/16 (38%) Burkitt lymphoma cell lines. PCBP1 is an intron-less gene encoding the 356 amino acid poly(rC) binding protein 1, which contains three K-Homology (KH) domains and two nuclear localization signals. The mutations predominantly (10/12, 83%) affect the KH III domain, either by complete domain loss or amino acid changes. Thus, these changes are predicted to alter the various functions of PCBP1, including nuclear trafficking and pre-mRNA splicing. Remarkably, all six primary Burkitt lymphomas with a PCBP1 mutation expressed MUM1/IRF4, which is otherwise detected in around 20-40% of Burkitt lymphomas. We conclude that PCBP1 mutations are recurrent in Burkitt lymphomas and might contribute, in cooperation with other mutations, to its pathogenesis.


Asunto(s)
Linfoma de Burkitt/genética , Ribonucleoproteínas Nucleares Heterogéneas/genética , Mutación , Adolescente , Adulto , Anciano , Linfoma de Burkitt/metabolismo , Línea Celular Tumoral , Niño , Preescolar , Estudios de Cohortes , Proteínas de Unión al ADN , Femenino , Expresión Génica , Ribonucleoproteínas Nucleares Heterogéneas/química , Ribonucleoproteínas Nucleares Heterogéneas/metabolismo , Humanos , Masculino , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas de Unión al ARN , Adulto Joven
15.
Lab Invest ; 94(8): 927-33, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24933424

RESUMEN

Alterations in the DNA methylome are characteristic for numerous diseases and a typical hallmark of cancer. Therefore, DNA methylation is currently under investigation in research labs and has also entered diagnostics. Recently, protocols like the BeadChip technology have become commercially available to study DNA methylation in an array format and semiquantitative fashion. However, it is known that fixation of the sample material with formalin prior to BeadChip analysis can affect the results. In this study we compared the influence of fixation on the outcome of BeadChip analysis. From six patients each a lung cancer tissue sample and a corresponding tumor-free lung tissue sample were collected. The samples were separated into three pieces. One piece of each sample was fixed with formalin, another one by the non-cross-linking HOPE technique (Hepes-glutamic acid buffer mediated Organic solvent Protection Effect). Subsequently, both became paraffin embedded. As a reference, the remaining third piece was cryopreserved. In addition we used three adenocarcinoma cell lines (H838, A549, and H1650) to validate the results from patient tissues. We show that using the HOPE technique instead of formalin largely prevents the introduction of formalin-fixation related artifacts. An ANOVA analysis significantly separated HOPE- and cryopreserved from formalin-fixed samples (FDR<0.05), while differences in the methylation data obtained from HOPE-fixed and cryopreserved material were minor. Consequently, HOPE fixation is superior to formalin fixation if a subsequent BeadChip analysis of paraffin-embedded sample material is intended.


Asunto(s)
Adenocarcinoma/metabolismo , Carcinoma de Células Escamosas/metabolismo , Metilación de ADN , ADN de Neoplasias/metabolismo , Neoplasias Pulmonares/metabolismo , Pulmón/metabolismo , Conservación de Tejido , Adenocarcinoma/patología , Anciano , Artefactos , Tampones (Química) , Carcinoma Adenoescamoso/metabolismo , Carcinoma Adenoescamoso/patología , Carcinoma de Células Grandes/metabolismo , Carcinoma de Células Grandes/prevención & control , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Criopreservación , ADN de Neoplasias/aislamiento & purificación , Femenino , Ácido Glutámico/química , HEPES/química , Humanos , Pulmón/patología , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Análisis de Matrices Tisulares , Fijación del Tejido
16.
J Med Genet ; 51(6): 407-12, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24721835

RESUMEN

BACKGROUND: In a subset of imprinting disorders caused by epimutations, multiple imprinted loci are affected. Familial occurrence of multilocus imprinting disorders is rare. PURPOSE/OBJECTIVE: We have investigated the clinical and molecular features of a familial DNA-methylation disorder. METHODS: Tissues of affected individuals and blood samples of family members were investigated by conventional and molecular karyotyping. Sanger sequencing and RT-PCR of imprinting-associated genes (NLRP2, NLRP7, ZFP57, KHDC3L, DNMT1o), exome sequencing and locus-specific, array-based and genome-wide technologies to determine DNA-methylation were performed. RESULTS: In three offspring of a healthy couple, we observed prenatal onset of severe growth retardation and dysmorphism associated with altered DNA-methylation at paternally and maternally imprinted loci. Array-based analyses in various tissues of the offspring identified the DNA-methylation of 2.1% of the genes in the genome to be recurrently altered. Despite significant enrichment of imprinted genes (OR 9.49), altered DNA-methylation predominately (90.2%) affected genes not known to be imprinted. Sequencing of genes known to cause comparable conditions and exome sequencing in affected individuals and their ancestors did not unambiguously point to a causative gene. CONCLUSIONS: The family presented herein suggests the existence of a familial disorder of DNA-methylation affecting imprinted but also not imprinted gene loci potentially caused by a maternal effect mutation in a hitherto not identified gene.


Asunto(s)
Metilación de ADN/genética , Enfermedades Genéticas Congénitas/genética , Alelos , Análisis Mutacional de ADN , Epigenómica , Femenino , Humanos , Recién Nacido , Masculino , Linaje
17.
Genes Chromosomes Cancer ; 53(4): 309-16, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24446122

RESUMEN

T-cell prolymphocytic leukemia (T-PLL) is an aggressive post-thymic T-cell malignancy characterized by the recurrent inv(14)(q11q32)/t(14;14)(q11;q32) or t(X;14)(q28;q11) leading to activation of either the TCL1 or MTCP1 gene, respectively. However, these primary genetic events are insufficient to drive leukemogenesis. Recently, activating mutations in JAK3 have been identified in other T-cell malignancies. Since JAK3 is essential for T-cell maturation, we analyzed a cohort of 32 T-PLL patients for mutational hot spots in the JAK3 gene using a step-wise screening approach. We identified 14 mutations in 11 of 32 patients (34%). The most frequently detected mutation in our cohort was M511I (seen in 57% of cases) previously described as an activating change in other T-cell malignancies. Three patients carried two mutations in JAK3. In two patients M511I and R657Q were simultaneously detected and in another patient V674F and V678L. In the latter case we could demonstrate that the mutations were on the same allele in cis. Protein modeling and homology analyses of mutations present in other members of the JAK family suggested that these mutations likely activate JAK3, possibly by disrupting the activation loop and the interface between N and C lobes, increasing the accessibility of the catalytic loop. In addition, four of the 21 patients lacking a JAK3 point mutation presented an aberrant karyotype involving the chromosomal band 19p13 harboring the JAK3 locus. The finding of recurrent activating JAK3 mutations in patients with T-PLL could enable the use of JAK3 inhibitors to treat patients with this unfavorable malignancy who otherwise have a very poor prognosis.


Asunto(s)
Cromosomas Humanos Par 14/genética , Janus Quinasa 3/genética , Leucemia Prolinfocítica de Células T/genética , Anciano , Secuencia de Aminoácidos , Estudios de Cohortes , Femenino , Humanos , Masculino , Datos de Secuencia Molecular , Mutación
18.
Eur J Hum Genet ; 21(8): 838-43, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23232699

RESUMEN

Various genes located at imprinted loci and regulated by epigenetic mechanisms are involved in the control of growth and differentiation. The broad phenotypic variability of imprinting disorders suggests that individuals with inborn errors of imprinting might remain undetected among patients born small for gestational age (SGA). We evaluated quantitative DNA methylation analysis at differentially methylated regions (DMRs) of 10 imprinted loci (PLAGL1, IGF2R DMR2, GRB10, H19 DMR, IGF2, MEG3, NDN, SNRPN, NESP, NESPAS) by bisulphite pyrosequencing in 98 patients born SGA and 50 controls. For IGF2R DMR2, methylation patterns of additional 47 parent pairs and one mother (95 individuals) of patients included in the SGA cohort were analyzed. In six out of 98 patients born SGA, we detected DNA methylation changes at single loci. In one child, the diagnosis of upd(14)mat syndrome owing to an epimutation of the MEG3 locus in 14q32 could be established. The remaining five patients showed hypomethylation at GRB10 (n=2), hypomethylation at the H19 3CTCF-binding site (n=1), hypermethylation at NDN (n=1) and hypermethylation at IGF2 (n=1). IGF2R DMR2 hypermethylation was detected in five patients, six parents of patients in the SGA cohort and two controls. We conclude that aberrant methylation at imprinted loci in children born SGA exists but seems to be rare if known imprinting syndromes are excluded. Further investigations on the physiological variations and the functional consequences of the detected aberrant methylation are necessary before final conclusions on the clinical impact can be drawn.


Asunto(s)
Metilación de ADN , Sitios Genéticos/genética , Impresión Genómica/genética , Recién Nacido Pequeño para la Edad Gestacional , Anomalías Múltiples/genética , Anomalías Múltiples/patología , Adolescente , Niño , Preescolar , Estudios de Cohortes , Salud de la Familia , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Linaje , Fenotipo , Análisis de Secuencia de ADN , Síndrome
19.
Horm Res Paediatr ; 77(2): 100-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22456342

RESUMEN

BACKGROUND/AIM: X-linked adrenal hypoplasia congenita (AHC) is a rare disorder characterized by primary adrenal insufficiency and hypogonadic hypogonadism. It is caused by deletions or point mutations of the NR0B1 gene, on Xp21. AHC can be associated with glycerol kinase deficiency, Duchenne muscular dystrophy and mental retardation (MR), as part of a contiguous gene deletion syndrome. A synthetic probe set for multiplex ligation-dependent probe amplification analysis was developed to confirm and characterize NR0B1 deletions in patients with AHC and to correlate their genotypes with their divergent phenotypes. RESULTS: In 2 patients, isolated AHC was confirmed, while a patient at risk for metabolic crisis was revealed as the deletion extends to the GK gene. A deletion extending to IL1RAPL1 was confirmed in both patients showing MR. Thus, a good genotype-phenotype correlation was confirmed. CONCLUSIONS: Multiplex ligation-dependent probe amplification analysis is a valuable tool to detect NR0B1 and contiguous gene deletions in patients with AHC. It is especially helpful for IL1RAPL1 deletion detection as no clinical markers for MR are available. Furthermore, multiplex ligation-dependent probe amplification has the advantage to identify female carriers that, depending on the deletion extension, have a high risk of giving birth to children with MR, AHC, glycerol kinase deficiency and Duchenne muscular dystrophy.


Asunto(s)
Hiperplasia Suprarrenal Congénita/genética , Hiperplasia Suprarrenal Congénita/fisiopatología , Receptor Nuclear Huérfano DAX-1/genética , Eliminación de Gen , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Enfermedades Genéticas Ligadas al Cromosoma X/fisiopatología , Sitios Genéticos , Adolescente , Hiperplasia Suprarrenal Congénita/metabolismo , Insuficiencia Suprarrenal , Adulto , Niño , Receptor Nuclear Huérfano DAX-1/metabolismo , Femenino , Estudios de Asociación Genética , Tamización de Portadores Genéticos/métodos , Enfermedades Genéticas Ligadas al Cromosoma X/metabolismo , Humanos , Insuficiencia Corticosuprarrenal Familiar , Lactante , Proteína Accesoria del Receptor de Interleucina-1/genética , Proteína Accesoria del Receptor de Interleucina-1/metabolismo , Masculino , Discapacidad Intelectual Ligada al Cromosoma X/genética , Madres , Reacción en Cadena de la Polimerasa Multiplex , Técnicas de Amplificación de Ácido Nucleico , Análisis de Secuencia por Matrices de Oligonucleótidos , Suecia
20.
Int J Cancer ; 130(6): 1319-28, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21500188

RESUMEN

Abberrant DNA methylation is one of the hallmarks of cancerogenesis. Our study aims to delineate differential DNA methylation in cirrhosis and hepatic cancerogenesis. Patterns of methylation of 27,578 individual CpG loci in 12 hepatocellular carcinomas (HCCs), 15 cirrhotic controls and 12 normal liver samples were investigated using an array-based technology. A supervised principal component analysis (PCA) revealed 167 hypomethylated loci and 100 hypermethylated loci in cirrhosis and HCC as compared to normal controls. Thus, these loci show a "cirrhotic" methylation pattern that is maintained in HCC. In pairwise supervised PCAs between normal liver, cirrhosis and HCC, eight loci were significantly changed in all analyses differentiating the three groups (p < 0.0001). Of these, five loci showed highest methylation levels in HCC and lowest in control tissue (LOC55908, CELSR1, CRMP1, GNRH2, ALOX12 and ANGPTL7), whereas two loci showed the opposite direction of change (SPRR3 and TNFSF15). Genes hypermethylated between normal liver to cirrhosis, which maintain this methylation pattern during the development of HCC, are depleted for CpG islands, high CpG content promoters and polycomb repressive complex 2 (PRC2) targets in embryonic stem cells. In contrast, genes selectively hypermethylated in HCC as compared to nonmalignant samples showed an enrichment of CpG islands, high CpG content promoters and PRC2 target genes (p < 0.0001). Cirrhosis and HCC show distinct patterns of differential methylation with regards to promoter structure, PRC2 targets and CpG islands.


Asunto(s)
Carcinoma Hepatocelular/genética , Metilación de ADN , Cirrosis Hepática/genética , Neoplasias Hepáticas/genética , Islas de CpG , Células Madre Embrionarias/metabolismo , Epigénesis Genética , Humanos , Proteínas del Grupo Polycomb , Análisis de Componente Principal/métodos , Regiones Promotoras Genéticas , Proteínas Represoras/genética , Reproducibilidad de los Resultados
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