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Venetoclax improves CD20 immunotherapy in a mouse model of MYC/BCL2 double-expressor diffuse large B-cell lymphoma. J Immunother Cancer 2023; 11:jitc-2022-006113. [PMID: 36854569 PMCID: PMC9980368 DOI: 10.1136/jitc-2022-006113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2023] [Indexed: 03/02/2023] Open
Abstract
BACKGROUND Approximately one-third of diffuse large B cell lymphoma (DLBCL) patients exhibit co-expression of MYC and BCL2 (double-expressor lymphoma, DEL) and have a dismal prognosis. Targeted inhibition of the anti-apoptotic protein BCL2 with venetoclax (ABT-199) has been approved in multiple B-cell malignancies and is currently being investigated in clinical trials for DLBCL. Whether BCL2 anti-apoptotic function represents a multifaceted vulnerability for DEL-DLBCL, affecting both lymphoma B cells and T cells within the tumor microenvironment, remains to be elucidated. METHODS Here, we present novel genetically engineered mice that preclinically recapitulate DEL-DLBCL lymphomagenesis, and evaluate their sensitivity ex vivo and in vivo to the promising combination of venetoclax with anti-CD20-based standard immunotherapy. RESULTS Venetoclax treatment demonstrated specific killing of MYC+/BCL2+ lymphoma cells by licensing their intrinsically primed apoptosis, and showed previously unrecognized immunomodulatory activity by specifically enriching antigen-activated effector CD8 T cells infiltrating the tumors. Whereas DEL-DLBCL mice were refractory to venetoclax alone, inhibition of BCL2 significantly extended overall survival of mice that were simultaneously treated with a murine surrogate for anti-CD20 rituximab. CONCLUSIONS These results suggest that the combination of anti-CD20-based immunotherapy and BCL2 inhibition leads to cooperative immunomodulatory effects and improved preclinical responses, which may offer promising therapeutic opportunities for DEL-DLBCL patients.
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p.Y317H is a new JAK2 gain-of-function mutation affecting the FERM domain in a myelofibrosis patient with CALR mutation. Haematologica 2017; 102:e328-e331. [PMID: 28473624 DOI: 10.3324/haematol.2017.166439] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
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3
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A simple approach for classifying new mutations as somatic or germinal in DNA samples lacking paired tissue. Biotechniques 2014; 56:327-9. [PMID: 24924393 DOI: 10.2144/000114180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 04/11/2014] [Indexed: 11/23/2022] Open
Abstract
When studying mutations in DNA samples, determining whether novel sequence changes are somatic mutations or germline polymorphisms can be difficult. Here we describe a novel and very simple approach for identification of somatic mutations and loss of heterozygosity (LoH) events in DNA samples where no matched tissue sample is available. Our method makes use of heterozygous polymorphisms that are located near the putative mutation to trace both germinal alleles.
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4
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Habit acquisition in the context of neuronal genomic and epigenomic mosaicism. Front Hum Neurosci 2014; 8:255. [PMID: 24795609 PMCID: PMC4007014 DOI: 10.3389/fnhum.2014.00255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 04/07/2014] [Indexed: 11/26/2022] Open
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5
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Oncofuse: a computational framework for the prediction of the oncogenic potential of gene fusions. ACTA ACUST UNITED AC 2013; 29:2539-46. [PMID: 23956304 DOI: 10.1093/bioinformatics/btt445] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
MOTIVATION Gene fusions resulting from chromosomal aberrations are an important cause of cancer. The complexity of genomic changes in certain cancer types has hampered the identification of gene fusions by molecular cytogenetic methods, especially in carcinomas. This is changing with the advent of next-generation sequencing, which is detecting a substantial number of new fusion transcripts in individual cancer genomes. However, this poses the challenge of identifying those fusions with greater oncogenic potential amid a background of 'passenger' fusion sequences. RESULTS In the present work, we have used some recently identified genomic hallmarks of oncogenic fusion genes to develop a pipeline for the classification of fusion sequences, namely, Oncofuse. The pipeline predicts the oncogenic potential of novel fusion genes, calculating the probability that a fusion sequence behaves as 'driver' of the oncogenic process based on features present in known oncogenic fusions. Cross-validation and extensive validation tests on independent datasets suggest a robust behavior with good precision and recall rates. We believe that Oncofuse could become a useful tool to guide experimental validation studies of novel fusion sequences found during next-generation sequencing analysis of cancer transcriptomes. AVAILABILITY AND IMPLEMENTATION Oncofuse is a naive Bayes Network Classifier trained and tested using Weka machine learning package. The pipeline is executed by running a Java/Groovy script, available for download at www.unav.es/genetica/oncofuse.html.
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6
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A meta-analysis of TET2 mutations shows a distinct distribution pattern in de novo acute myeloid leukemia and chronic myelomonocytic leukemia. Leuk Lymphoma 2012; 53:1230-3. [PMID: 22080757 DOI: 10.3109/10428194.2011.639878] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
MESH Headings
- Age of Onset
- DNA-Binding Proteins/genetics
- Dioxygenases
- Gene Frequency
- Humans
- Leukemia, Myeloid, Acute/diagnosis
- Leukemia, Myeloid, Acute/epidemiology
- Leukemia, Myeloid, Acute/genetics
- Leukemia, Myelomonocytic, Chronic/diagnosis
- Leukemia, Myelomonocytic, Chronic/epidemiology
- Leukemia, Myelomonocytic, Chronic/genetics
- Mutation/physiology
- Myelodysplastic Syndromes/epidemiology
- Myelodysplastic Syndromes/genetics
- Myeloproliferative Disorders/epidemiology
- Myeloproliferative Disorders/genetics
- Proto-Oncogene Proteins/genetics
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7
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LIF, a Novel STAT5-Regulated Gene, Is Aberrantly Expressed in Myeloproliferative Neoplasms. Genes Cancer 2011; 2:593-6. [PMID: 21901172 DOI: 10.1177/1947601911420139] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 06/08/2011] [Accepted: 07/11/2011] [Indexed: 12/20/2022] Open
Abstract
A search for genes potentially regulated by STAT5 identified leukemia inhibitory factor (LIF) as a good candidate. Using various experimental approaches, we have validated LIF as a direct transcriptional target of STAT5 in myeloid cell lines: STAT5 binds to LIF promoter, and LIF expression is increased after activation of the JAK2/STAT5 pathway. We also found that LIF expression is significantly increased in patients with chronic myeloproliferative neoplasms with and without activating mutations of the pathway, indicating that LIF might play an important role in STAT5-mediated oncogenesis.
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8
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Quantification of PDGFRA alternative transcripts improves the screening for X-PDGFRA fusions by reverse transcriptase-polymerase chain reaction. Leuk Lymphoma 2010; 51:1720-6. [PMID: 20615084 DOI: 10.3109/10428194.2010.497575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Hematological malignancies with eosinophilia are often associated with fusions in PDGFRA, PDGFRB, or FGFR1 genes. RT-PCR has proved to be useful for finding new PDGFRA gene fusions, but some studies have shown overexpression of the TK domain which cannot be explained by the existence of such aberrations. This fact could be related to the expression of alternative PDGFRA transcripts. We show that quantification of the expression of three different PDGFRA fragments discriminates between PDGFRA alternative transcripts and fusion genes, and we have tested this novel methodological approach in a group of eosinophilia cases. Our data show that alternative PDGFRA transcripts should be taken into account when screening for PDGFRA aberrations, such as gene fusions, by RT-PCR. Expression from an internal PDGFRA promoter seems to be a frequent event, in both normal and leukemic samples, and is probably related to physiological conditions, but it could have a role in other tumors. Even so, we show that our RQ-PCR methodology can discriminate expression of alternative transcripts from the presence of X-PDGFRA fusion genes.
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9
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A new potential oncogenic mutation in the FERM domain of JAK2 in BCR/ABL1-negative and V617F-negative chronic myeloproliferative neoplasms revealed by a comprehensive screening of 17 tyrosine kinase coding genes. ACTA ACUST UNITED AC 2010; 199:1-8. [DOI: 10.1016/j.cancergencyto.2010.01.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2009] [Revised: 12/14/2009] [Accepted: 01/03/2010] [Indexed: 12/13/2022]
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10
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Signatures of selection in fusion transcripts resulting from chromosomal translocations in human cancer. PLoS One 2009; 4:e4805. [PMID: 19279687 PMCID: PMC2653638 DOI: 10.1371/journal.pone.0004805] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2008] [Accepted: 01/30/2009] [Indexed: 11/27/2022] Open
Abstract
Background The recurrence and non-random distribution of translocation breakpoints in human tumors are usually attributed to local sequence features present in the vicinity of the breakpoints. However, it has also been suggested that functional constraints might contribute to delimit the position of translocation breakpoints within the genes involved, but a quantitative analysis of such contribution has been lacking. Methodology We have analyzed two well-known signatures of functional selection, such as reading-frame compatibility and non-random combinations of protein domains, on an extensive dataset of fusion proteins resulting from chromosomal translocations in cancer. Conclusions Our data provide strong experimental support for the concept that the position of translocation breakpoints in the genome of cancer cells is determined, to a large extent, by the need to combine certain protein domains and to keep an intact reading frame in fusion transcripts. Additionally, the information that we have assembled affords a global view of the oncogenic mechanisms and domain architectures that are used by fusion proteins. This can be used to assess the functional impact of novel chromosomal translocations and to predict the position of breakpoints in the genes involved.
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11
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[Negative results related to drugs required in hospitalisation]. FARMACIA HOSPITALARIA 2009; 33:12-25. [PMID: 19401093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
OBJECTIVE To assess the prevalence of negative clinical outcomes associated with medication as a cause of hospital admission and to determine their characteristics (types, categories, avoidability, severity and the drug groups involved.) To determine possible risk factors related to the appearance of this problem. METHOD An observational study carried out over a three month period in a department of the university hospital, 163 patients were selected at random. The information obtained from the patient interview, the revision of clinical records and clinical sessions were used to then identify negative clinical outcomes using the Dader method. RESULTS In 27 cases (16.6 %; 95 % confidence interval [CI], 1.6 to 23.0), negative clinical outcomes associated with medication were considered to be the main cause of hospital admission. The most frequent negative clinical outcomes associated with medication were untreated health problems, non-quantitative ineffectiveness and quantitative safety problems respectively. The overall prevalence of preventable admissions due to negative clinical outcomes associated with medication was 88.9 %; (95 % CI, 71.9 to 96.1 %.) With regards to severity, 74.1 % (95 % CI, 55.3 to 86.1 %) of the total admissions were moderate. The most common drugs implicated in hospital admissions were: antibacterial for systemic use, cardiovascular and non steroidal anti-inflammatory agents. Apart from age, no other factors were found for hospital admissions due to negative results associated with medication. CONCLUSIONS Negative clinical outcomes associated with medication as cause of hospital admission are a prevalent problem and most of them are avoidable with pharmacotherapeutic follow-up.
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12
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Methylation status of SOCS1 and SOCS3 in BCR-ABL negative and JAK2V617F negative chronic myeloproliferative neoplasms. Leuk Res 2008; 32:1638-40. [PMID: 18440067 DOI: 10.1016/j.leukres.2008.03.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Revised: 03/14/2008] [Accepted: 03/15/2008] [Indexed: 01/26/2023]
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13
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TICdb: a collection of gene-mapped translocation breakpoints in cancer. BMC Genomics 2007; 8:33. [PMID: 17257420 PMCID: PMC1794234 DOI: 10.1186/1471-2164-8-33] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2006] [Accepted: 01/26/2007] [Indexed: 12/02/2022] Open
Abstract
Background Despite the importance of chromosomal translocations in the initiation and/or progression of cancer, a comprehensive catalog of translocation breakpoints in which these are precisely located on the reference sequence of the human genome is not available at present. Description We have created a database that describes the genomic location of 1,225 translocation breakpoints in human tumors, corresponding to 247 different genes, using information from publicly available sources. Junction sequences from reciprocal translocations were obtained from 655 different references (either from the literature or from nucleotide databases), and were mapped onto the reference sequence of the human genome using BLAST. All translocation breakpoints were thus referred to precise nucleotide positions (949 breakpoints) or gene fragments (introns or exons, 276 breakpoints) within specific Ensembl transcripts. Conclusion TICdb is a comprehensive collection of finely mapped translocation breakpoints, freely available at . It should facilitate the analysis of sequences encompassing translocation breakpoints and the identification of factors driving translocation events in human tumors.
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14
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Chromosome translocations in cancer: computational evidence for the random generation of double-strand breaks. Trends Genet 2006; 22:193-6. [PMID: 16499992 DOI: 10.1016/j.tig.2006.02.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2005] [Revised: 01/12/2006] [Accepted: 02/01/2006] [Indexed: 11/28/2022]
Abstract
In this article, we show that introns harboring translocation breakpoints in tumors are significantly longer than non-translocated introns of the same genes but are not enriched significantly in sequence elements potentially involved in chromosomal rearrangements. Our findings provide evidence that double-strand breaks, the type of DNA damage that leads to translocations in tumors, are created at random points in the genome, and that sequence elements do not have a widespread role in the localization of these breaks.
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15
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FISH analysis of hematological neoplasias with 1p36 rearrangements allows the definition of a cluster of 2.5 Mb included in the minimal region deleted in 1p36 deletion syndrome. Hum Genet 2005; 116:476-85. [PMID: 15744521 DOI: 10.1007/s00439-005-1268-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2004] [Accepted: 01/04/2005] [Indexed: 01/01/2023]
Abstract
Rearrangements in the distal region of the short arm of chromosome 1 are recurrent aberrations in a broad spectrum of human neoplasias. However, neither the location of the breakpoints (BP) on 1p36 nor the candidate genes have been fully determined. We have characterized, by fluorescence in situ hybridization (FISH), the BP in 26 patients with hematological neoplasias and 1p36 rearrangements in the G-banding karyotype. FISH allowed a better characterization of all samples analyzed. Nine cases (35%) showed reciprocal translocations, 15 (58%) unbalanced rearrangements, and two (7%) deletions. We describe two new recurrent aberrations. In 18 of the 26 cases analyzed the BP were located in band 1p36, which is 25.5 Mb long. In 14 of these 18 cases (78%) and without distinction between myeloid and lymphoid neoplasias, the BP clustered in a 2.5 Mb region located between 1p36.32 and the telomere. Interestingly, this region is contained in the 10.5 Mb cluster on 1p36.22-1pter defined in cases with 1p36 deletion syndrome. The 2.5 Mb region, located on 1p36.32-1pter, has a higher frequency of occurrence of tandem repeats and segmental duplications larger than 1 kb, when compared with the 25.5 Mb of the complete 1p36 band. This could explain its proneness for involvement in chromosomal rearrangements in hematological neoplasias.
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16
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Remission of acute monocytic leukemia, secondary to treatment with epipodophyllotoxins, in a patient with t(8;16)(p11;p13) and MYST3–CREBBP fusion. ACTA ACUST UNITED AC 2004; 152:177-8. [PMID: 15262444 DOI: 10.1016/j.cancergencyto.2003.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
MESH Headings
- Adult
- Antineoplastic Agents, Phytogenic/adverse effects
- Bone Marrow Transplantation
- Chromosome Banding
- Chromosomes, Human, Pair 16/genetics
- Chromosomes, Human, Pair 8/genetics
- Humans
- In Situ Hybridization, Fluorescence
- Karyotyping
- Leukemia, Monocytic, Acute/chemically induced
- Leukemia, Monocytic, Acute/genetics
- Leukemia, Monocytic, Acute/therapy
- Male
- Oncogene Proteins, Fusion/genetics
- Podophyllotoxin/adverse effects
- Remission Induction
- Translocation, Genetic/genetics
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17
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NIN, a Gene Encoding a CEP110-Like Centrosomal Protein, Is Fused to PDGFRB in a Patient with a t(5;14)(q33;q24) and an Imatinib-Responsive Myeloproliferative Disorder
1. Cancer Res 2004; 64:2673-6. [PMID: 15087377 DOI: 10.1158/0008-5472.can-04-0144] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We describe a new PDGFRB fusion associated with a t(5;14)(q33;q24) in a patient with a longstanding chronic myeloproliferative disorder with eosinophilia. After confirmation of PDGFRB involvement and definition of the chromosome 14 breakpoint by fluorescence in situ hybridization, candidate partner genes were selected on the basis of the presence of predicted oligomerization domains believed to be an essential feature of tyrosine kinase fusion proteins. We demonstrate that the t(5;14) fuses PDGFRB to NIN, a gene encoding a centrosomal protein with CEP110-like function. After treatment with imatinib, the patient achieved hematological and cytogenetical remission, but NIN-PDGFRB mRNA remained detectable by reverse transcription-PCR.
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MESH Headings
- Adult
- Antineoplastic Agents/therapeutic use
- Base Sequence
- Benzamides
- Chromosomes, Human, Pair 14/genetics
- Chromosomes, Human, Pair 5/genetics
- Gene Rearrangement
- Humans
- Imatinib Mesylate
- In Situ Hybridization, Fluorescence
- Male
- Molecular Sequence Data
- Myeloproliferative Disorders/drug therapy
- Myeloproliferative Disorders/genetics
- Oncogene Proteins, Fusion/genetics
- Piperazines/therapeutic use
- Pyrimidines/therapeutic use
- Receptor Protein-Tyrosine Kinases/genetics
- Receptor, Fibroblast Growth Factor, Type 1
- Receptor, Platelet-Derived Growth Factor beta/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Translocation, Genetic
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18
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TP53 is frequently altered by methylation, mutation, and/or deletion in acute lymphoblastic leukaemia. Mol Carcinog 2004; 38:201-8. [PMID: 14639659 DOI: 10.1002/mc.10159] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Different mechanisms, such as chromosomal rearrangements, deletions, mutations, and methylation/demethylation of the promoter regions of genes, have been shown to be involved in acute lymphoblastic leukaemia (ALL). These genetic and epigenetic alterations lead to the activation of protooncogenes or to inactivation of tumour suppressor genes promoting cell proliferation. One of the most frequently inactivated tumour suppressor genes is TP53, which is altered in 50% of human tumours. In this study, we have analysed: (1) the complete coding region, all intron-exon junctions and noncoding regions of exons 1-11 of TP53 by lexon-DGGE; (2) the methylation status of the 5' region of TP53 and (3) the deletion of one or both alleles of the gene by fluorescence in situ hybridisation (FISH) in 57 ALL patients. Using these techniques, we have found promoter methylation in 32% of the cases, missense mutations in 8.8%, and deletion of one allele in 7.5% of the samples, with TP53 being altered in 40% of the ALL samples studied in this series.
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19
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In vivo sustained release of adenoviral vectors from poly(d,l-lactic-co-glycolic) acid microparticles prepared by TROMS. J Control Release 2004; 94:229-35. [PMID: 14684286 DOI: 10.1016/j.jconrel.2003.10.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have prepared and characterised injectable adenovirus-loaded polymeric microparticles to be used for in vitro and in vivo gene transfer studies. Microparticles were prepared by the water-in-oil-in-water solvent evaporation method using a novel system where the emulsification process is carried out by the turbulent injection of the phases in the total recirculation one-machine system (TROMS) apparatus. In vitro studies were performed to assess the amount of infectious adenovirus released from the microparticles, showing that these microparticles release higher amounts of infectious adenovirus than microparticles prepared by standard emulsification techniques. We also tested whether sustained release in vivo could overcome the short-lived gene expression profile which is typical of adenovirus delivery into muscle. Intramuscular injection of adenovirus-loaded microparticles in immunocompetent mice showed transgene (beta-galactosidase) expression for at least 7 weeks in two out of four muscles injected with adenovirus-loaded microparticles prepared by TROMS, but not in control muscles injected with purified adenovirus stocks.
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t(10;16)(q22;p13) and MORF-CREBBP fusion is a recurrent event in acute myeloid leukemia. Genes Chromosomes Cancer 2003; 36:402-5. [PMID: 12619164 DOI: 10.1002/gcc.10174] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Recently, it was shown that t(10;16)(q22;p13) fuses the MORF and CREBBP genes in a case of childhood acute myeloid leukemia (AML) M5a, with a complex karyotype containing other rearrangements. Here, we report a new case with the MORF-CREBBP fusion in an 84-year-old patient diagnosed with AML M5b, in which the t(10;16)(q22;p13) was the only cytogenetic aberration. This supports that this is a recurrent pathogenic translocation in AML.
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MESH Headings
- Acetyltransferases/genetics
- Aged
- Aged, 80 and over
- CREB-Binding Protein
- Chromosomes, Human, Pair 10/genetics
- Chromosomes, Human, Pair 16/genetics
- Cytogenetic Analysis/methods
- Fatal Outcome
- Histone Acetyltransferases
- Humans
- Leukemia, Monocytic, Acute/diagnosis
- Leukemia, Monocytic, Acute/genetics
- Male
- Neoplasm Recurrence, Local/genetics
- Nuclear Proteins/genetics
- Oncogene Proteins, Fusion/genetics
- Saccharomyces cerevisiae Proteins/genetics
- Trans-Activators/genetics
- Translocation, Genetic/genetics
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21
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Methylation of CpG dinucleotides and/or CCWGG motifs at the promoter of TP53 correlates with decreased gene expression in a subset of acute lymphoblastic leukemia patients. Oncogene 2003; 22:1070-2. [PMID: 12592393 DOI: 10.1038/sj.onc.1206236] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
It has been shown that methylation of CpG dinucleotides located in the promoter region of TP53 is associated with low expression levels of this gene. We have analysed the methylation status of one CpG dinucleotide and of three CCWGG motifs, also located in the promoter region of the gene, in bone marrow samples obtained from patients with acute lymphoblastic leukemia (ALL). Eight out of 25 samples analysed showed methylation of either the CpG dinucleotide, the CCWGG motifs or both. Relative to nonmethylated leukemia samples, TP53 expression levels were decreased in all methylated samples in which TP53 expression could be measured. Methylation of CpG and CCWGG motifs in the promoter of TP53 could represent a novel mechanism leading to functional impairment of this tumor suppressor gene in ALL.
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22
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Loading of plasmid DNA into PLGA microparticles using TROMS (Total Recirculation One-Machine System): evaluation of its integrity and controlled release properties. J Control Release 2003; 86:123-30. [PMID: 12490378 DOI: 10.1016/s0168-3659(02)00371-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Loading plasmid DNA into poly(ester) microparticles usually involves the formation of a multiple emulsion, using homogenisation techniques such as sonication or Ultra-Turrax. These procedures may negatively affect the integrity of the macromolecule and consequently its activity. The aim of this study was to prepare and evaluate DNA-loaded microparticles by TROMS (Total Recirculation One-Machine System), a new procedure that is based on the formation of a multiple emulsion by the injection of the phases under a turbulent regime. Microparticles were prepared with either Resomer) RG 502 (MP 502) or RG 756 (MP 756) and DNA loading was quantified fluorimetrically. DNA loading in MP 756 was almost twice as high as in MP 502 (510 vs. 285 ng/mg, respectively). Under both formulations, the loaded plasmid was released while maintaining its integrity for at least 24 days (MP 502) and 40 days (MP 756). Finally, the transfection efficiency was studied after injection of the microparticles (MP 502) into rat skeletal muscle and compared with naked DNA injection. Injection of naked DNA (150 microg DNA per muscle) achieved higher but variable expression levels that decreased after 3 weeks. In contrast, the muscles injected with microparticles (6.8 microg DNA per muscle) showed lower but homogeneous expression values, which were maintained for at least 3 weeks.
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23
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24
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IGF1 gene transfer into skeletal muscle using recombinant adeno-associated virus in a rat model of liver cirrhosis. J Physiol Biochem 2002; 58:169-76. [PMID: 12603011 DOI: 10.1007/bf03179854] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Systemic administration of recombinant IGF1 at low levels has been shown to improve hepatic function, nutritional status and testicular atrophy in rats with CCl4-induced cirrhosis. We have developed a recombinant adeno-associated (rAAV) viral vector containing the cDNA for rat IGF1 and confirmed the expression of IGF1 after intramuscular injection of this vector in a rat model of liver cirrhosis. Although weight of injected muscles was significantly increased in rats with mild cirrhosis, this was not the case in rats with advanced, de-compensated cirrhosis. Furthermore, we found no significant amelioration of liver damage in treated rats at any stage of liver cirrhosis. Our results suggest that IGF1 gene transfer into muscle results in a local effect, at least at the vector dose employed here.
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25
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A novel gene, MDS2, is fused to ETV6/TEL in a t(1;12)(p36.1;p13) in a patient with myelodysplastic syndrome. Genes Chromosomes Cancer 2002; 35:11-9. [PMID: 12203785 DOI: 10.1002/gcc.10090] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
ETV6/TEL is the first transcription factor identified that is specifically required for hematopoiesis within the bone marrow. This gene has been found to have multiple fusion partners of which 16 have been cloned. Fluorescence in situ hybridization (FISH) analysis in a patient with myelodysplastic syndrome (MDS) revealed a t(1;12)(p36;p13) involving ETV6, with the breakpoint in this gene between exon 2 and exon 3. We report here the cloning of a novel ETV6 partner located on 1p36.1, involved in the t(1;12). 3' RACE-PCR from RNA identified a novel sequence fused to exon 2 of ETV6. Database searches localized this sequence in a bacterial artificial chromosome (BAC) mapped to 1p36 by fingerprint analysis. This result was confirmed by FISH using this BAC as probe. 5' and 3' RACE experiments with primers from this novel sequence were carried out on RNA from a healthy donor and identified a novel full-length mRNA, which we named MDS2 (myelodysplastic syndrome 2). RT-PCR experiments were performed on a panel of human cDNAs to analyze the expression pattern of this gene and they revealed four splicing variants. RT-PCR analysis showed that ETV6-MDS2, but not the reciprocal MDS2-ETV6 fusion transcript, was expressed in the bone marrow of the patient. The product of the ETV6-MDS2 fusion transcript predicts a short ETV6 protein containing the first 54 amino acids of ETV6 plus four novel amino acids, lacking both the PTN and the DNA-binding domains. Possible mechanisms to account for the development of MDS in this patient are discussed.
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MESH Headings
- Aged
- Amino Acid Sequence/genetics
- Base Sequence/genetics
- Bone Marrow Cells/metabolism
- Bone Marrow Cells/physiology
- Chromosome Painting
- Chromosomes, Human, Pair 1/genetics
- Chromosomes, Human, Pair 12/genetics
- Cloning, Molecular/methods
- DNA-Binding Proteins/genetics
- Female
- Gene Expression Regulation, Neoplastic/genetics
- Genes, Neoplasm/genetics
- Humans
- In Situ Hybridization, Fluorescence
- Karyotyping
- Molecular Sequence Data
- Myelodysplastic Syndromes/genetics
- Nuclear Proteins/genetics
- Oncogene Proteins, Fusion/genetics
- Proteins/genetics
- Proto-Oncogene Proteins c-ets
- RNA, Neoplasm/genetics
- Repressor Proteins/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Translocation, Genetic/genetics
- ETS Translocation Variant 6 Protein
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26
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Abstract
Mitochondrial uncoupling protein 1 (UCP1) mediates the thermogenic transport of protons through the inner mitochondrial membrane. This proton leak uncouples respiration from ATP synthesis. The current study assessed the possible contribution of UCP1 muscle gene transfer to impair mitochondrial respiration in a tissue lacking UCP1 gene expression. Rats received an intramuscular injection of plasmid pXC1 containing UCP1 cDNA in the right tibialis muscles, while left tibialis muscles were injected with empty plasmid as control. Ten days after DNA injection, mitochondria from tibialis anterior muscles were isolated and analyzed. UCP1 gene transfer resulted in protein expression as analyzed by inmunoblotting. Mitochondria isolated from UCP1-injected muscles showed a significant increase in state 2 and state 4 oxygen consumption rates and a decreased respiration control ratio in comparison to mitochondria from control muscles. Furthermore, UCP1-containing mitochondria had a lower membrane potential in those states (2 and 4) when compared with control mitochondria. Our results revealed that UCP1 muscle gene transfer is associated with an induced mitochondrial proton leak, which could contribute to increase energy expenditure.
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27
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[Prevalence of CYPD6 mutations in sporadic Parkinson's disease: case-control study]. An Sist Sanit Navar 2002; 25:147-54. [PMID: 12861292 DOI: 10.23938/assn.0795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Genetic factors seem to play an important role in the development of Parkinson's disease. The degeneration of the sustantia nigra, characteristic of this disease, might be due to the toxic effect of substances derived from cellular metabolism. The CYP2D6 gene codifies for the metabolising enzyme debrisoquie-4-hydroxilase involved in the detoxification of part of these products. The presence of determinate mutations in the gene implies a lack of enzymatic activity and generates the "poor metaboliser" phenotype. By means of the PCR-RFLP technique, the presence of the genetic mutations CYP2D6 3, CYP2D6 4, CYP2D6 6 and CYP2D6 8 has been analysed in a group of 46 patients with PD and in 54 controls, with the aim of studying the possible value of genotype CYP2D6 as a risk factor for Parkinson's disease in the population of Navarra. The alleles CYP2D6 3, 6 and 8 are not represented in the sample studied. We have not obtained a greater presence of CYP2D6 4 mutations in the patients with respect to the controls (30.43% vs. 44.44%). There is no correlation between Parkinson's disease and the presence of CYP2D6 4 mutations (odds ratio 0.55; 95% CI 0.24 to 1.25), in homozygosis (odds ratio 0.38; 95% CI 0.04 to 3.76) or in heterozygosis (odds ratio 0.62; 95% CI 0.27 to 1.44). In conclusion, the genotype CYP2D6 does not constitute a risk factor in PD.
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28
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Exon concatenation to increase the efficiency of mutation screening by DGGE. Biotechniques 2002; 32:1064-5, 1068-70. [PMID: 12019779 DOI: 10.2144/02325rr01] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
For genes that have a substantial number of exons and long intronic sequences, mutation screening by denaturing gradient gel electrophoresis (DGGE) requires the amplification of each exon from genomic DNA by PCR. This results in a high number of fragments to be analyzed by DGGE so that the analysis of large sample sets becomes labor intensive and time consuming. To address this problem, we have developed a new strategy for mutation analysis, lexon-DGGE, which combines the joining of different exons by PCR (also known as lexons) with a highly sensitive technique such as DGGE to screen for mutations. The lexon technique is based on the concatenation of several exons, adjacent or not, from genomic DNA into a single DNA fragment so that this approach could simultaneously be used to check the mutational status of several small genes. To show the feasibility of the approach, we have used the lexon-DGGE technique to analyze all coding exons, intron-exon junctions, noncoding exon 1, and part of the noncoding region of exon 11 of the TP53 gene. The validity and performance of the technique were confirmed by using negative and positive controls for each of the DNAfragments analyzed.
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29
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Interphase FISH assays for the detection of translocations with breakpoints in immunoglobulin light chain loci. Int J Cancer 2002; 98:470-4. [PMID: 11920602 DOI: 10.1002/ijc.10169] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Many B-cell malignancies bear chromosomal translocations juxtaposing immunoglobulin (IG) genes with oncogenes, resulting in deregulated expression of the latter. Translocations affecting the IG heavy chain (IGH) locus in chromosomal region 14q32 are most prevalent. However, variant translocations involving the IG kappa (IGK) locus in 2p12 or the IG lambda (IGL) locus in 22q11 occur recurrently in B-cell neoplasias. No routine methods for the detection of all breakpoints involving IG light chain loci independently of the translocation partner have been described. For this reason, we have designed 2 novel interphase fluorescence in situ hybridization (FISH) assays using differentially labeled probes flanking the IGK and IGL locus, respectively. Based on extensive control studies, the diagnostic thresholds for the detection of breakpoints were set at 0.3% for IGK and 1.4% for IGL. Fifteen cases of B-cell malignancies with cytogenetically detectable chromosomal abnormalities in 2p11-14 were investigated with the FISH assay for IGK. Breakpoints affecting the IGK locus were detected in 7 cases including all 4 variant Burkitt's translocations t(2;8)(p12;q24) and a variant BCL2-associated translocation t(2;18)(p12;q21). Other translocation partners were chromosome bands 7q21 and 16q24. Ten cases with abnormalities in 22q11-12 were investigated with the FISH assay for IGL. Breakpoints in the IGL locus were diagnosed in 7 cases including both variant Burkitt's translocations t(8;22)(q24;q11) and a t(3;22)(q27;q11) involving the BCL6 locus. Other translocation partners were 2p13-14, 4q13 and 16p12. Our results show that these FISH assays provide flexible, simple and reliable tools in the diagnosis and characterization of genetic changes in B-cell malignancies.
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MESH Headings
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Child
- Chromosome Aberrations
- Chromosomes, Human, Pair 14
- Chromosomes, Human, Pair 16
- Chromosomes, Human, Pair 2
- Chromosomes, Human, Pair 22
- Chromosomes, Human, Pair 4
- Chromosomes, Human, Pair 8
- Female
- Genes, Immunoglobulin/genetics
- Humans
- In Situ Hybridization, Fluorescence
- Interphase
- Lymphoma, B-Cell/genetics
- Male
- Middle Aged
- Translocation, Genetic
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30
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Abstract
Comparative genomic hybridization studies have shown gains in chromosome region 2p as the most common imbalance in classical Hodgkin lymphoma (cHL). The minimal region of gain contained 2 candidate oncogenes, REL and BCL11A. This study examined the involvement of REL and BCL11A loci in 44 primary cases of cHL by combined immunophenotyping and interphase cytogenetics (FICTION). A median 2p13 copy number above the tetraploid range was detected in 24 (55%) cases. Adjustment for centromere 2 copy number indicated gains of 2p13 in 11 of 31 cHLs (35%) with 8 (26%) high-level amplifications. One cHL displayed selective amplification of the REL locus not affecting BCL11A; another case studied by FICTION and a cHL with cytogenetic 2p change investigated by fluorescence in situ hybridization showed signal patterns suggesting breakpoints in the region spanned by the REL probe. These data indicate that REL rather than BCL11A may be the target of the 2p13 alterations in cHL.
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31
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Amplification of ERBB2, RARA, and TOP2A genes in a myelodysplastic syndrome transforming to acute myeloid leukemia. CANCER GENETICS AND CYTOGENETICS 2001; 127:174-6. [PMID: 11425459 DOI: 10.1016/s0165-4608(00)00431-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A patient is described with myelodysplastic syndrome (MDS) progressing to acute myeloid leukemia (AML) FAB M4. Cytogenetic analysis revealed an unusual rearrangement between chromosomes 9 and 17, leading to a dicentric chromosome with an insertion of material of unknown origin between both chromosomes. By fluorescence in situ hybridization (FISH), the insertion was shown to be an amplification of part of 17q, involving ERBB2, RARA, and TOP2A genes. The median copy number of ERBB2, RARA, and TOP2A genes in the tumor cells was six (range: 4--10). Only one copy of the MPO gene at 17q21.3 was detected, suggesting a deletion of the telomeric part of 17q. To our knowledge, this is the first report of a 17q amplification in AML.
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MESH Headings
- Antigens, Neoplasm/genetics
- Antineoplastic Combined Chemotherapy Protocols/administration & dosage
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Cell Transformation, Neoplastic/genetics
- Chromosome Aberrations
- Chromosome Mapping
- Chromosomes, Human, Pair 17
- Chromosomes, Human, Pair 9
- Cytarabine/administration & dosage
- DNA Topoisomerases, Type II/genetics
- DNA-Binding Proteins
- Daunorubicin/administration & dosage
- Female
- Genes, erbB-2
- Humans
- In Situ Hybridization, Fluorescence
- Isoenzymes/genetics
- Karyotyping
- Leukemia, Myelomonocytic, Acute/drug therapy
- Leukemia, Myelomonocytic, Acute/genetics
- Leukemia, Myelomonocytic, Acute/pathology
- Metaphase
- Middle Aged
- Myelodysplastic Syndromes/genetics
- Myelodysplastic Syndromes/pathology
- Poly-ADP-Ribose Binding Proteins
- Receptors, Retinoic Acid/genetics
- Retinoic Acid Receptor alpha
- Thioguanine/administration & dosage
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32
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Insertion (22;9)(q11;q34q21) in a patient with chronic myeloid leukemia characterized by fluorescence in situ hybridization. ACTA ACUST UNITED AC 2001; 125:167-70. [PMID: 11369063 DOI: 10.1016/s0165-4608(00)00370-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An unusual cytogenetic rearrangement, described as ins(22;9)(q11;q34q21), was detected in a 49-year-old male patient diagnosed with chronic myeloid leukemia (CML). Reverse transcriptase polymerase chain reaction (RT-PCR) revealed a b3a2 fusion transcript. In order to confirm the cytogenetic findings and fully characterize the inverted insertion, we performed fluorescence in situ hybridization (FISH) assays using locus-specific and whole chromosome painting probes. Our FISH analysis showed the presence of the BCR/ABL fusion gene, verified the insertion and determined that the breakpoint on chromosome 22 where the insertion took place was located proximal to the BCR gene and distal to the TUPLE1 gene on 22q11.
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MESH Headings
- Biomarkers, Tumor/analysis
- Biomarkers, Tumor/genetics
- Bone Marrow/pathology
- Chromosome Banding
- Chromosome Breakage
- Chromosome Inversion
- Chromosome Painting
- Chromosomes, Human, Pair 22/genetics
- Chromosomes, Human, Pair 22/ultrastructure
- Chromosomes, Human, Pair 9/genetics
- Chromosomes, Human, Pair 9/ultrastructure
- Clone Cells/pathology
- Fusion Proteins, bcr-abl/analysis
- Fusion Proteins, bcr-abl/genetics
- Humans
- Karyotyping
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Male
- Middle Aged
- Models, Genetic
- Mutagenesis, Insertional
- Reverse Transcriptase Polymerase Chain Reaction
- Translocation, Genetic
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33
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Abstract
OBJECTIVE The aim of this work was to evaluate the effect of uncoupling protein 2 (UCP2) muscle gene transfer on mitochondrial activity. DESIGN Five week-old male Wistar rats received an intramuscular injection of plasmid pXU1 containing UCP2 cDNA in the right tibialis anterior muscles. Left tibialis anterior muscles were injected with vehicle as control. Ten days after DNA injection, tibialis anterior muscles were dissected and muscle mitochondria isolated and analyzed. RESULTS There were two mitochondrial populations in the muscle after UCP2 gene transfer, one of low fluorescence and complexity and the other, showing high fluorescence and complexity. UCP2 gene transfer resulted in a 3.6 fold increase in muscle UCP2 protein levels compared to control muscles assessed by Western blotting. Furthermore, a significant reduction in mitochondria membrane potential assessed by spectrofluorometry and flow cytometry was observed. The mitochondria membrane potential reduction might account for a decrease in fluorescence of the low fluorescence mitochondrial subpopulation. CONCLUSION It has been demonstrated that UCP2 muscle gene transfer in vivo is associated with a lower mitochondria membrane potential. Our results suggest the potential involvement of UCP2 in uncoupling respiration. International Journal of Obesity (2001) 25, 68-74
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34
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[Significance of human mitochondrial genome in medicine]. REVISTA DE MEDICINA DE LA UNIVERSIDAD DE NAVARRA 2001; 45:29-42. [PMID: 11488205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Mitochondrial function is necessary for energy production, but also plays important roles in oxidative stress and apoptosis. Part of the complexes responsible for mitochondrial metabolism are encoded in mitochondrial DNA (mtDNA). Knowledge of the structure and function of mtDNA affords a better understanding of (1) the physiopathology of mitochondrial disorders; (2) the pattern of inheritance of mitochondrial diseases; and (3) the strategies that can be employed in the molecular diagnosis of these disorders. In the near future important breakthroughs are expected regarding the understanding of the cross-talk between nuclear and mitochondrial genomes, and its relevance in the biogenesis and maintenance of mitochondria.
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35
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[Genetic alterations in hematological neoplasias of lymphoid origin: implications for clinical practice]. An Sist Sanit Navar 2000; 23:451-65. [PMID: 12886300 DOI: 10.23938/assn.0763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The improvement of the conventional cytogenetic techniques, the development of molecular cytogenetics and the application of techniques of molecular biology to genetic analysis have led to an authentic revolution in the knowledge of the processes implied in the development and progression of lymphoid neoplasias. In this way, a great part of the alterations present in malign cells have been characterised, and the genes involved in the transformative process have been established. This has important consequences for the clinical handling of this type of disease and makes possible a more exact diagnosis through a systematisation of the different entities based on their biological characteristics. On the other hand, the introduction of new techniques of analysis, such as real time PCR, will make it possible to monitor the disease quantitatively, making it possible to evaluate response to the different treatments and to establish predictive values for relapses. In the future, all of this knowledge will make it possible to establish genotype-specific therapies and to develop new medicines aimed at the alteration responsible for the malignant process and with less undesired collateral effects.
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36
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Method to decrease the titers of contaminating helper adenovirus during the production of recombinant adeno-associated virus. Biotechniques 2000; 28:1096, 1098, 1100. [PMID: 10868274 DOI: 10.2144/00286bm08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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37
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Abstract
The production of peptide hormones by skeletal muscle tissue is a promising area of gene therapy. Skeletal muscle myogenesis can be induced in vitro, resulting in the fusion of mononucleate myoblasts to form multinucleate myotubes, and delivery vectors are first tested in vitro. C2C12 myoblasts transfected with pcDNA3-GH, which used the human cytomegalovirus (CMV) promoter, secreted immunoreactive GH with comparable biological activity to pituitary GH. Mouse myeloid leukaemia cells, which express the mouse GH receptor were used for the bioassay, and activation of these cells by GH was measured by a colorimetric microculture tetrazolium assay. Cells were incubated with a tetrazolium salt (MTS) and an intermediate electron acceptor (phenazine methosulphate, PMS), and formazan production was measured as optical density (O.D.) at 490 nm. The efficiencies of several plasmid expression vectors were compared in differentiated and non-differentiated muscle cells, as a function of bioactive GH secreted by the transfected cells. Ten-day differentiated C2C12 myotubes transfected with pcDNA3E-GH, which used the CMV promoter and a rat myosin light chain enhancer element, secreted significantly more biologically active GH than myotubes transfected with pcDNA3-GH (0.82 O.D. units+/-0.06 vs 0.57+/-0.05 respectively, P<0.001). This was consistent with reduced CMV promoter activity in myotubes. Myoblasts transfected with pcDNA3-GH secreted more bioactive GH than 10-day transfected myotubes (1.1+/-0. 1 vs 0.77+/-0.07 respectively). However, the responses were indistinguishable (both 1.0+/-0.09) if both the myotubes and myoblasts had been transfected with pcDNA3E-GH. Substitution of the vector pMHLC-GH, which used a muscle-specific truncated rabbit myosin heavy chain promoter, and the myosin enhancer resulted in a marked decrease in the responses to the conditioned medium from fused myotubes compared with the vectors pcDNA3-GH and pcDNA3E-GH (0. 24+/-0.02 vs 0.57+/-0.05 vs 0.82+/-0.06 respectively). We concluded that the combination of CMV promoter and myosin light chain enhancer in pcDNA3E-GH had the greatest expression efficiency of the several plasmid vectors which we investigated.
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38
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Degree and distribution of variability in the 5' untranslated, E1, E2/NS1 and NS5 regions of the hepatitis C virus (HCV). J Viral Hepat 1998; 5:227-40. [PMID: 9751009 DOI: 10.1046/j.1365-2893.1998.00110.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Hepatitis C virus (HCV) shows a high degree of variability resulting in many different variants. In this work we described the variability of several subgenomic fragments from the 5' untranslated region (5'-UTR) and E1, E2/NS1 and NS5 regions comparing, for every position, all the sequences published in GenBank v. 88 (July 1995) as well as new sequences obtained in this work. Variability was determined in two ways. First, we analysed the degree and type of substitutions found in these regions. Second, we defined the most variable and conserved segments in each region and compared our prediction with previous studies. Our results confirm that HCV variability changes along the different regions. Although we found four variable domains in the 5'-UTR, this region was the only one to contain conserved domains. Envelope (E1, E2/NS1) and NS5 regions showed high variability throughout; however, we were able to define six and three hypervariable domains, respectively. The degree and distribution of variability established in this work is supported by the high number of sequences and the different types included in the study. Knowledge of how variability is distributed along the different regions of the HCV genome could be of use in the design of new diagnostic and therapeutic strategies against HCV infection.
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39
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Leptin gene transfer into muscle increases lipolysis and oxygen consumption in white fat tissue in ob/ob mice. Biochem Biophys Res Commun 1998; 246:859-62. [PMID: 9618302 DOI: 10.1006/bbrc.1998.8539] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effects of leptin production in ob/ob mice injected with a plasmid expression vector containing mouse leptin cDNA in the tibialis anterior muscle were investigated. A significant reduction in food intake (-18%, p < 0.01) along the experimental period was found after DNA injection, while differences in body weight gain were only significant (-41%, p < 0.05) when determined between days 2.9 of the study. Concerning adipocytes metabolism, there was a significant increase in oxygen consumption in vitro (+34%, p < 0.05) and in basal lipolysis (+151%, p < 0.05) in DNA-injected mice compared to PBS-injected animals. Our results confirm that functional leptin can be produced in muscle and released into the blood stream and give new support to the fact that leptin may have direct auto- or paracrine effects on adipocytes, possible contributing to the weight- and fat-reducing effects of leptin in ob/ob mice.
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40
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Gene transfer and expression of human alpha-galactosidase from mouse muscle in vitro and in vivo. Gene Ther 1997; 4:488-92. [PMID: 9274727 DOI: 10.1038/sj.gt.3300410] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Lysosomal storage disorders are amenable to treatment by enzyme replacement. Genetic modification of muscle via direct injection of expression vectors might represent an alternative method of providing the defective enzymes, if adequate and long-lasting expression levels can be achieved in muscle. We have used the C2C12 mouse myogenic cell line to study the effect of combination of muscle-specific regulatory elements on the expression of the human lysosomal enzyme alpha-galactosidase (alpha-gal). In differentiated myotubes, a construct containing the myosin light chain 1/3 enhancer in combination with the human cytomegalovirus promoter resulted in higher expression than constructs combining the same enhancer with the rabbit beta-myosin heavy chain promoter, or containing the CMV promoter only. Increased enzymatic activity was detectable both in cell extracts and in supernatants. Furthermore, human fibroblasts deficient in alpha-gal were able to take up the enzyme from medium conditioned by transfected myoblasts. This did not occur in the presence of mannose-6-phosphate which indicates that the uptake was via mannose-6-phosphate receptors. To our knowledge, this is the first report in which a correctly processed form of human alpha-gal was expressed and secreted from differentiated muscle cells. Direct injection of a plasmid expression vector into mouse tibialis anterior muscle showed significantly increased levels of alpha-gal 7 days after injection.
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41
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Editors and embryos. Nat Med 1996; 2:1280. [PMID: 8946815 DOI: 10.1038/nm1296-1280a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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42
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Editing of human alpha-galactosidase RNA resulting in a pyrimidine to purine conversion. Nucleic Acids Res 1995; 23:2636-40. [PMID: 7503918 PMCID: PMC307086 DOI: 10.1093/nar/23.14.2636] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
During a study of the gene coding for alpha-galactosidase (EC 3.2.1.22), the lysosomal enzyme deficient in Fabry's disease, RT-PCR amplification of alpha-galactosidase mRNAs obtained from three different tissues isolated from males revealed a substantial number of clones with a U to A conversion at the nucleotide position 1187. Such a modification of the coding sequence would result in an amino acid substitution in the C-terminal region (Phe396Tyr) of the enzyme. Neither PCR analysis of the genomic sequence nor the RT-PCR amplification of RNA obtained by in vitro transcription of the wild-type cDNA showed this change in the sequence. Multiple genes, pseudogenes are allelic variants were excluded. Hence, we propose RNA editing as a mechanism responsible for this base change in the alpha-galactosidase RNA.
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43
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Abstract
A total of 54 YAC clones have been isolated from the region of Xp22.2-p22.3 extending from the amelogenin gene locus to DXS31. Restriction analysis of these clones in association with STS contenting and end clone analysis has facilitated the construction of 6 contigs covering a total of 7 Mb in which 20 potential CpG islands have been located. Thirty new STSs have been developed from probe and YAC end clone sequences, and these have been used in the analysis of patients suffering from different combinations of chondrodysplasia punctata, mental retardation, X-linked ichthyosis, and Kallmann syndrome. The results suggest that (1) the gene for chondrodysplasia punctata must lie between the X chromosome pseudoautosomal boundary (PABX) and DXS1145; (2) a gene for mental retardation lies between DXS1145 and the sequence tagged site GS1; and (3) the gene for ocular albinism type 1 lies proximal to the STS G13. The CpG islands within the YAC contigs constitute valuable markers for the potential positions of genes. Genes found associated with any of these potential CpG islands would be possible candidates for the disease genes mentioned above.
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A de-sialylated isoform of serum 5'-nucleotidase: clinical and biological significance in hepatobiliary disease. Br J Biomed Sci 1994; 51:119-23. [PMID: 8049608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Using an electrophoretic technique on cellulose acetate, three multiple forms of the 5'-nucleotidase (5'NU) with mobilities alpha 1, alpha 2, and beta appear in the serum of healthy subjects. The difference between the alpha 1 and alpha 2 isoforms lies in their sialylation degree, the alpha 2-5'NU being a de-sialylated form. In 147 patients with different hepatobiliary diseases the alpha 2 isoform was present in only 19% of cases, and there was no significant difference in the activity of total 5'NU, alpha 1-5'NU and beta-5'NU between patients with or without alpha 2-5'NU, alpha 1-5'NU and beta-5'NU (P < 0.001), as with other biochemical indicators of liver damage. It is suggested that in hepatobiliary diseases an increase of the sialylation of serum 5'NU occurs, which would explain the absence of the desialylated alpha 2 isoform in the majority of cases. However, the decrease of hepatic receptors of asialoglycoproteins would lead to an increase of this de-sialylated isoform in the serum of certain patients.
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45
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Changes in Alkaline Phosphatase and 5'-Nucleotidase Multiple Forms After Surgical Management of Biliary Obstruction. Clin Chem 1992. [DOI: 10.1093/clinchem/38.7.1340] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Serial measurements of alkaline phosphatase and 5'-nucleotidase multiple forms in two patients undergoing surgical procedures to release biliary obstruction suggested an inverse relationship between high-M(r) isoforms and serum bile acids concentrations. Furthermore, the study of several groups of patients with cholestatic disorders confirmed this inverse correlation. Mechanisms responsible for these observations are discussed.
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46
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Changes in alkaline phosphatase and 5'-nucleotidase multiple forms after surgical management of biliary obstruction. Clin Chem 1992; 38:1340-2. [PMID: 1623601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Serial measurements of alkaline phosphatase and 5'-nucleotidase multiple forms in two patients undergoing surgical procedures to release biliary obstruction suggested an inverse relationship between high-M(r) isoforms and serum bile acids concentrations. Furthermore, the study of several groups of patients with cholestatic disorders confirmed this inverse correlation. Mechanisms responsible for these observations are discussed.
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Wheat germ agglutinin binding to serum 5'-nucleotidase and alkaline phosphatase. Clin Chim Acta 1991; 203:101-2. [PMID: 1663008 DOI: 10.1016/0009-8981(91)90162-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Abstract
A procedure is proposed for the separation of multiple forms of 5'-nucleotidase (EC 3.1.3.5) by cellulose acetate electrophoresis. The effects of various treatments (wheat-germ lectin, neuraminidase, n-butanol, papain, Triton X-100 and precipitation of LDL and VLDL) on the electrophoretic pattern of 5'-nucleotidase and alkaline phosphatase were studied. In healthy controls, the presence of three fractions with alpha 1, alpha 2 and beta mobilities was observed, the latter being the major one. In different hepatobiliary diseases a close relationship between the presence of high molecular weight alkaline phosphatase and the increase in the ratio Total/beta 5'-nucleotidase was observed, showing that the increase in total 5'-nucleotidase in these patients is mainly due to the alpha 1 isoform. The nature of these forms is discussed.
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