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1.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806448

RESUMO

Lambda interferons mediate antiviral immunity by inducing interferon-stimulated genes (ISGs) in epithelial tissues. A common variant rs368234815TT/∆G creating functional gene from an IFNL4 pseudogene is associated with the expression of major ISGs in the liver but impaired clearance of hepatitis C. To explain this, we compared Halo-tagged and non-tagged IFNL3 and IFNL4 signaling in liver-derived cell lines. Transfection with non-tagged IFNL3, non-tagged IFNL4 and Halo-tagged IFNL4 led to a similar degree of JAK-STAT activation and ISG induction; however, the response to transfection with Halo-tagged IFNL3 was lower and delayed. Transfection with non-tagged IFNL3 or IFNL4 induced no transcriptome change in the cells lacking either IL10R2 or IFNLR1 receptor subunits. Cytosolic overexpression of signal peptide-lacking IFNL3 or IFNL4 in wild type cells did not interfere with JAK-STAT signaling triggered by interferons in the medium. Finally, expression profile changes induced by transfection with non-tagged IFNL3 and IFNL4 were highly similar. These data do not support the hypothesis about IFNL4-specific non-canonical signaling and point out that functional studies conducted with tagged interferons should be interpreted with caution.


Assuntos
Hepatócitos/imunologia , Hepatócitos/metabolismo , Interferons/genética , Interferons/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Linhagem Celular , Expressão Gênica , Técnicas de Inativação de Genes , Células Hep G2 , Humanos , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Interferons/deficiência , Subunidade beta de Receptor de Interleucina-10/deficiência , Subunidade beta de Receptor de Interleucina-10/genética , Subunidade beta de Receptor de Interleucina-10/metabolismo , Interleucinas/deficiência , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Interferon/deficiência , Receptores de Interferon/genética , Receptores de Interferon/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Transfecção
2.
Genes Chromosomes Cancer ; 59(7): 396-405, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32170980

RESUMO

The karyotype of bone-marrow cells at the time of diagnosis is one of the most important prognostic factors in patients with myelodysplastic syndromes (MDS). In some cases, the acquisition of additional genetic aberrations (clonal evolution [CE]) associated with clinical progression may occur during the disease. We analyzed a cohort of 469 MDS patients using a combination of molecular cytogenomic methods to identify cryptic aberrations and to assess their potential role in CE. We confirmed CE in 36 (8%) patients. The analysis of bone-marrow samples with a combination of cytogenomic methods at diagnosis and after CE identified 214 chromosomal aberrations. The early genetic changes in the diagnostic samples were frequently MDS specific (17 MDS-specific/57 early changes). Most progression-related aberrations identified after CE were not MDS specific (131 non-MDS-specific/155 progression-related changes). Copy number neutral loss of heterozygosity (CN-LOH) was detected in 19% of patients. MDS-specific CN-LOH (4q, 17p) was identified in three patients, and probably pathogenic homozygous mutations were found in TET2 (4q24) and TP53 (17p13.1) genes. We observed a statistically significant difference in overall survival (OS) between the groups of patients divided according to their diagnostic cytogenomic findings, with worse OS in the group with complex karyotypes (P = .021). A combination of cytogenomic methods allowed us to detect many cryptic genomic changes and identify genes and genomic regions that may represent therapeutic targets in patients with progressive MDS.


Assuntos
Evolução Clonal , Síndromes Mielodisplásicas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Proteínas de Ligação a DNA/genética , Dioxigenases , Feminino , Humanos , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Mutação , Síndromes Mielodisplásicas/classificação , Síndromes Mielodisplásicas/patologia , Prognóstico , Proteínas Proto-Oncogênicas/genética , Análise de Sobrevida , Proteína Supressora de Tumor p53/genética
3.
Cas Lek Cesk ; 158(1): 22-27, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31046388

RESUMO

In patients with hematological malignancies one of the most substantial findings is the karyotype of bone marrow cells at the time of diagnosis. The detection of clonal chromosome aberrations in diagnostic samples not only confirms a neoplastic or premalignant process but also provides important diagnostic and prognostic information essential for precise disease classification and choice of suitable therapy. Karyotype analysis during the disease course also allows monitoring of the treatment success reflected as well in the revised WHO classification where patients are often classified into the different diagnostic subtypes based on the finding of specific chromosome and/or genetic changes. Recently, also increases the number of advanced treatment approaches that directly or indirectly target the genetic aberrations present in tumor cells. Despite the large development of new sequencing technologies in recent years, cytogenetic analysis supplemented by the molecular cytogenetic methods still remains a very important part of diagnostics of hematological malignancies.


Assuntos
Aberrações Cromossômicas , Análise Citogenética , Neoplasias Hematológicas , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/genética , Humanos , Cariotipagem , Prognóstico
4.
Hematol Oncol ; 36(1): 110-115, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29083050

RESUMO

Implementation of cytarabine into induction therapy became standard of care for younger patients with mantle cell lymphoma (MCL). On the basis of its beneficial impact, many centers incorporated cytarabine at lower doses also into first-line treatments of elderly patients. We conducted a multicenter observational study that prospectively analyzed safety and efficacy of alternating 3 + 3 cycles of R-CHOP and R-cytarabine for newly diagnosed transplant-ineligible MCL patients. A total of 73 patients were enrolled with median age 70 years. Most patients had intermediate (39.7%) and high-risk (50.7%) disease according to MCL international prognostic index. Rituximab maintenance was initiated in 58 patients. Overall response rate reached 89% by positron emission tomography-computed tomography, including 75.3% complete remissions. Two patients (2.7%) did not complete the induction therapy because of toxicity. Three patients (4.1%) were considered nonresponders, which led to therapy change before completion of induction. Estimated progression-free survival and overall survival were 51.3% and 68.6% at 4 years, respectively. Mantle cell lymphoma international prognostic index, bulky disease (≥ 5 cm), and achievement of positron emission tomography-negativity independently correlated with progression-free survival. Grade 3 to 4 hematologic and nonhematologic toxicity was documented in 48% and 20.5% patients, respectively. Alternation of R-CHOP and R-cytarabine represents feasible and very effective regimen for elderly/comorbid MCL patients. This study was registered at GovTrial (clinicaltrials.gov) NCT03054883.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Citarabina/uso terapêutico , Linfoma de Célula do Manto/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Murinos/farmacologia , Anticorpos Monoclonais Murinos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ciclofosfamida/farmacologia , Ciclofosfamida/uso terapêutico , Citarabina/farmacologia , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Feminino , Humanos , Linfoma de Célula do Manto/patologia , Masculino , Pessoa de Meia-Idade , Prednisona/farmacologia , Prednisona/uso terapêutico , Rituximab , Vincristina/farmacologia , Vincristina/uso terapêutico
5.
Int J Cancer ; 139(10): 2252-60, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27407063

RESUMO

Richter syndrome represents the transformation of the chronic lymphocytic leukemia (CLL) into an aggressive lymphoma, most frequently the diffuse large B-cell lymphoma (DLBCL). In this report we describe a patient with CLL, who developed a clonally-related pleomorphic highly-aggressive mantle cell lymphoma (MCL) after five cycles of a fludarabine-based second-line therapy for the first relapse of CLL. Molecular cytogenetic methods together with whole-exome sequencing revealed numerous gene alterations restricted to the MCL clone (apart from the canonical t(11;14)(q13;q32) translocation) including gain of one copy of ATM gene or emergence of TP53, CREBBP, NUP214, FUBP1 and SF3B1 gene mutations. Similarly, gene expression analysis revealed vast differences between the MCL and CLL transcriptome, including overexpression of cyclin D1, downregulation of cyclins D2 and D3, or downregulation of IL4R in the MCL clone. Backtracking analysis using quantitative PCR specifically detecting an MCL-restricted focal deletion of TP53 revealed that the pre-MCL clone appeared in the bone marrow and peripheral blood of the patient approximately 4 years before the clinical manifestation of MCL. Both molecular cytogenetic and sequencing data support the hypothesis of a slow development of the pre-MCL clone in parallel to CLL over several years, and thereby exclude the possibility that the transformation event occurred at the stage of the CLL relapse clone by mere t(11;14)(q13;q32) acquisition.


Assuntos
Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 14 , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Leucemia Linfocítica Crônica de Células B/metabolismo , Perda de Heterozigosidade , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Linfoma de Célula do Manto/metabolismo , Pessoa de Meia-Idade , Translocação Genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
6.
Genes Chromosomes Cancer ; 54(11): 655-67, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26303387

RESUMO

Diffuse astrocytomas and oligodendrogliomas (WHO grade II) are the most common histological subtypes of low-grade gliomas (LGGs). Several molecular and epigenetic markers have been identified that predict tumor progression. Our aim was in detail to investigate the genetic and epigenetic background of LGGs and to identify new markers that might play a role in tumor behavior. Twenty-three patients with oligodendroglioma or oligoastrocytoma (LGO) and 22 patients with diffuse astrocytoma (LGA) were investigated using several molecular-cytogenetic and molecular methods to assess their copy number variations, mutational status and level of promoter methylation. The most frequent findings were a 1p/19q codeletion in 83% of LGO and copy-neutral loss of heterozygosity (CN-LOH) of 17p in 72% of LGA. Somatic mutations in the isocitrate dehydrogenase 1 or 2 (IDH1/IDH2) genes were detected in 96% of LGO and 91% of LGA. The O-6-methylguanine-DNA-methyltransferase (MGMT) promoter was methylated in 83% of LGO and 59% of LGA. MutL homolog 3 (MLH3) promoter methylation was observed in 61% of LGO and 27% of LGA. Methylation of the MGMT promoter, 1p/19q codeletion, mutated IDH1, and CN-LOH of 17p were the most frequent genetic aberrations in LGGs. The findings were more diverse in LGA than in LGO. To the best of our knowledge, this is the first time description of methylation of the MLH3 gene promoter in LGGs. Further studies are required to determine the role of the methylated MLH3 promoter and the other aberrations detected.


Assuntos
Astrocitoma/genética , Neoplasias Encefálicas/genética , Proteínas de Transporte/genética , Metilação de DNA , Epigênese Genética , Oligodendroglioma/genética , Astrocitoma/metabolismo , Biomarcadores Tumorais , Neoplasias Encefálicas/metabolismo , Proteínas de Transporte/metabolismo , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas MutL , Gradação de Tumores , Oligodendroglioma/metabolismo , Prognóstico
7.
Eur J Haematol ; 95(4): 352-60, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25600340

RESUMO

OBJECTIVE: A new interleukin-6 (IL-6)-dependent plasma cell leukemia cell line UHKT-944 was established from bone marrow cells derived from a 55-yr-old man with plasma cell leukemia. RESULTS: The cell line possesses phenotypic characteristics of plasma cells including the production of a monoclonal immunoglobulin IgA1-kappa. VH3-9 region of IgVH genes was rearranged and somatically hypermutated. The UHKT-944 cells were found to be negative for most of tested B-cell, T-cell, and myeloid markers. According to cytogenetic analysis, the cells were classified as near tetraploid with several numerical and structural abnormalities including the t(14;20) involving IgH locus. CONCLUSION: The established permanent plasma cell leukemia cell line is a suitable model for the study of cellular and molecular mechanisms of pathogenesis of this rare malignant disease.


Assuntos
Leucemia Plasmocitária/metabolismo , Leucemia Plasmocitária/patologia , Biomarcadores , Linhagem Celular Tumoral , Proliferação de Células , Análise Citogenética , Humanos , Imunoglobulinas/genética , Imunoglobulinas/metabolismo , Imunofenotipagem , Leucemia Plasmocitária/diagnóstico , Masculino , Pessoa de Meia-Idade
8.
Eur J Haematol ; 95(1): 35-43, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25287904

RESUMO

OBJECTIVES: Lenalidomide is a potent drug with pleiotropic effects in patients with myelodysplastic syndrome (MDS) with deletion of the long arm of chromosome 5 [del(5q)]. We investigated its effect on regulation of microRNA (miRNA) expression profiles in del(5q) patients with MDS in vivo. METHODS: We used miRNA expression microarrays to study changes in miRNA levels in peripheral blood CD14+ monocytes collected from patients before and during lenalidomide treatment and compared them with those from healthy donors. RESULTS: Before treatment, we observed strong upregulation of pro-apoptotic miR-34a and miR-34a* that diminished during lenalidomide exposure. Upregulation of HOX-related miR-196b and erythroid-specific miR-451 seen in untreated patients remained unchanged after the treatment. At the time of hematologic response, expression of several miRNAs clustering to the 14q32 locus was reduced. Additionally, we focused more deeply on miRNAs from the 5q commonly deleted region and found that levels of miR-378 and miR-378* followed haploinsufficiency trend. CONCLUSIONS: This report describes changes in miRNA expression in del(5q) patients with MDS treated with lenalidomide, likely arising from deregulation of pathways implicated in lenalidomide action.


Assuntos
Anemia Macrocítica/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica , Fatores Imunológicos/uso terapêutico , MicroRNAs/genética , Síndromes Mielodisplásicas/tratamento farmacológico , Talidomida/análogos & derivados , Idoso , Anemia Macrocítica/genética , Anemia Macrocítica/metabolismo , Anemia Macrocítica/patologia , Estudos de Casos e Controles , Deleção Cromossômica , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 5/genética , Cromossomos Humanos Par 5/metabolismo , Feminino , Perfilação da Expressão Gênica , Loci Gênicos , Estudo de Associação Genômica Ampla , Haploinsuficiência , Humanos , Lenalidomida , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia , Cultura Primária de Células , Splicing de RNA , Transdução de Sinais , Talidomida/uso terapêutico
9.
Eur J Haematol ; 95(1): 27-34, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25284710

RESUMO

Downregulation of cereblon (CRBN) gene expression is associated with resistance to the immunomodulatory drug lenalidomide and poor survival outcomes in multiple myeloma (MM) patients. However, the importance of CRBN gene expression in patients with myelodysplastic syndrome (MDS) and its impact on lenalidomide therapy are not clear. In this study, we evaluate cereblon expression in mononuclear cells isolated from bone marrow [23 lower risk MDS patients with isolated 5q deletion (5q-), 37 lower risk MDS patients with chromosome 5 without the deletion of long arms (non-5q-), and 24 healthy controls] and from peripheral blood (38 patients with 5q-, 52 non-5q- patients and 25 healthy controls) to gain insight into, firstly, the role of cereblon in lower risk MDS patients with or without 5q deletion and, secondly, into the mechanisms of lenalidomide action. Patients with 5q- lower risk MDS have the highest levels of CRBN mRNA in comparison with both lower risk MDS without the deletion of long arms of chromosome 5 and healthy controls. CRBN gene expression was measured using the quantitative TaqMan real-time PCR. High levels of CRBN mRNA were detected in all lenalidomide responders during the course of therapy. A significant decrease of the CRBN mRNA level during lenalidomide treatment is associated with loss of response to treatment and disease progression. These results suggest that, similar to the treatment of MM, high levels of full-length CRBN mRNA in lower risk 5q- patients are necessary for the efficacy of lenalidomide.


Assuntos
Anemia Macrocítica/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica , Fatores Imunológicos/uso terapêutico , Síndromes Mielodisplásicas/tratamento farmacológico , Peptídeo Hidrolases/genética , RNA Mensageiro/genética , Talidomida/análogos & derivados , Proteínas Adaptadoras de Transdução de Sinal , Anemia Macrocítica/genética , Anemia Macrocítica/metabolismo , Anemia Macrocítica/patologia , Estudos de Casos e Controles , Deleção Cromossômica , Cromossomos Humanos Par 5/genética , Cromossomos Humanos Par 5/metabolismo , Humanos , Lenalidomida , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia , Peptídeo Hidrolases/metabolismo , Polimorfismo de Nucleotídeo Único , Splicing de RNA , RNA Mensageiro/metabolismo , Transdução de Sinais , Talidomida/uso terapêutico , Resultado do Tratamento , Ubiquitina-Proteína Ligases
10.
Lab Invest ; 94(7): 806-17, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24862967

RESUMO

Mantle cell lymphoma (MCL) is an aggressive type of B-cell non-Hodgkin lymphoma (NHL) associated with poor prognosis. Animal models of MCL are scarce. We established and characterized various in vivo models of metastatic human MCL by tail vein injection of either primary cells isolated from patients with MCL or established MCL cell lines (Jeko-1, Mino, Rec-1, Hbl-2, and Granta-519) into immunodeficient NOD.Cg-Prkdc(scid) Il2rg(tm1Wjl)/SzJ mice. MCL infiltration was assessed with immunohistochemistry (tissues) and flow cytometry (peripheral blood). Engraftment of primary MCL cells was observed in 7 out of 12 patient samples. The pattern of engraftment of primary MCL cells varied from isolated involvement of the spleen to multiorgan infiltration. On the other hand, tumor engraftment was achieved in all five MCL cell lines used and lymphoma involvement of murine bone marrow, spleen, liver, and brain was observed. Overall survival of xenografted mice ranged from 22 ± 1 to 54 ± 3 days depending on the cell line used. Subsequently, we compared the gene expression profile (GEP) and phenotype of the engrafted MCL cells compared with the original in vitro growing cell lines (controls). We demonstrated that engrafted MCL cells displayed complex changes of GEP, protein expression, and sensitivity to cytotoxic agents when compared with controls. We further demonstrated that our MCL mouse models could be used to test the therapeutic activity of systemic chemotherapy, monoclonal antibodies, or angiogenesis inhibitors. The characterization of MCL murine models is likely to aid in improving our knowledge in the disease biology and to assist scientists in the preclinical and clinical development of novel agents in relapsed/refractory MCL patients.


Assuntos
Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Linfoma de Célula do Manto/genética , Transcriptoma/genética , Idoso , Animais , Medula Óssea/metabolismo , Encéfalo/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Imunofenotipagem , Subunidade gama Comum de Receptores de Interleucina/deficiência , Subunidade gama Comum de Receptores de Interleucina/genética , Estimativa de Kaplan-Meier , Fígado/metabolismo , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Pessoa de Meia-Idade , Baço/metabolismo , Transplante Heterólogo , Células Tumorais Cultivadas
11.
Hematol Oncol ; 32(2): 82-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23949951

RESUMO

The translocation t(2;11)(p21;q23) is associated with de novo myelodysplastic syndromes (MDS) and has an overall frequency of approximately 1%. The outcome of MDS patients with this translocation is not clear until now, because most of the clinical data addressing the t(2;11)(p21;q23) has been collected without investigating the status of the mixed lineage leukemia (MLL) gene. In this report, we present seven new patients with MDS diagnosis and the t(2;11)(p21;q23) in bone marrow cells; all of them without MLL gene rearrangement. They were found in two databases consisting of 1185 patients of two Czech institutions. These patients tended to be younger and showed a strong male predominance. A cytological and histological assessment of bone marrow at diagnosis revealed only mild MDS with marked dysplasia in megakaryopoiesis. Similar to other primary abnormalities in MDS (e.g. deletion of 11q), the t(2;11)(p21;q23) was frequently associated with deletion of 5q. Our results stress the common clinicopathological features of this entity and indicate that the t(2;11)(p21;q23) may be associated with a good prognosis for MDS patients (median survival 72 months).


Assuntos
Cromossomos Humanos Par 11 , Cromossomos Humanos Par 2 , Síndromes Mielodisplásicas/genética , Proteína de Leucina Linfoide-Mieloide/genética , Translocação Genética , Adulto , Idoso , Rearranjo Gênico , Histona-Lisina N-Metiltransferase , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/patologia , Prognóstico
12.
Genes Chromosomes Cancer ; 52(7): 619-35, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23580398

RESUMO

Chromosome 11 abnormalities are found in many hematological malignancies. In acute myeloid leukemia (AML), a proto-oncogene MLL (11q23.3) is frequently altered. However, rearrangements involving other regions of chromosome 11 have been reported. Therefore, we have characterized the chromosome 11 breakpoints and common deleted and amplified areas in the bone marrow or peripheral blood cells of newly diagnosed patients with AML. Using molecular-cytogenetic methods (multicolor fluorescence in situ hybridization (mFISH), multicolor banding (mBAND), microarrays, and FISH with bacterial artificial chromosome (BAC) probes, chromosome 11 abnormalities were delineated in 54 out of 300 (18%) newly diagnosed AML patients. At least 36 different chromosome 11 breakpoints were identified; two were recurrent (11p15.4 in the NUP98 gene and 11q23.3 in the MLL gene), and three were possibly nonrandom: 11p13 (ch11:29.31-31.80 Mb), 11p12 (ch11:36.75-37.49 Mb) and 11q13.2 (68.31-68.52 Mb). One new MLL gene rearrangement is also described. No commonly deleted region of chromosome 11 was identified. However, some regions were affected more often: 11pter-11p15.5 (n = 4; ch11:0-3.52 Mb), 11p14.1-11p13 (n = 4; ch11:28.00-31.00 Mb) and 11p13 (n = 4; ch11:31.00-31.50 Mb). One commonly duplicated (3 copies) region was identified in chromosomal band 11q23.3-11q24 (n = 9; ch11:118.35-125.00 Mb). In all eight cases of 11q amplification (>3 copies), only the 5' part of the MLL gene was affected. This study highlights several chromosome 11 loci that might be important for the leukemogeneic process in AML.


Assuntos
Pontos de Quebra do Cromossomo , Deleção Cromossômica , Cromossomos Humanos Par 11/genética , Leucemia Mieloide Aguda/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Feminino , Amplificação de Genes , Humanos , Hibridização in Situ Fluorescente , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Proto-Oncogene Mas , Adulto Jovem
13.
Ann Hematol ; 92(1): 11-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22965552

RESUMO

Friend leukemia virus integration 1 (Fli1) and erythroid Krüppel-like factor (EKLF) participate under experimental conditions in the differentiation of megakaryocytic and erythroid progenitor in cooperation with other transcription factors, cytokines, cytokine receptors, and microRNAs. Defective erythropoiesis with refractory anemia and effective megakaryopoiesis with normal or increased platelet count is typical for 5q- syndrome. We decided to evaluate the roles of EKLF and Fli1 in the pathogenesis of this syndrome and of another ribosomopathy, Diamond-Blackfan anemia (DBA). Fli1 and EKLF mRNA levels were examined in mononuclear blood and bone marrow cells from patients with 5q- syndrome, low-risk MDS patients with normal chromosome 5, DBA patients, and healthy controls. In 5q- syndrome, high Fli1 mRNA levels in the blood and bone marrow mononuclear cells were found. In DBA, Fli1 expression did not differ from the controls. EKLF mRNA level was significantly decreased in the blood and bone marrow of 5q- syndrome and in all DBA patients. We propose that the elevated Fli1 in 5q- syndrome protects megakaryocytic cells from ribosomal stress contrary to erythroid cells and contributes to effective though dysplastic megakaryopoiesis.


Assuntos
Anemia de Diamond-Blackfan/genética , Anemia Macrocítica/genética , Eritropoese/genética , Fatores de Transcrição Kruppel-Like/fisiologia , Proteína Proto-Oncogênica c-fli-1/fisiologia , Trombopoese/genética , Adolescente , Adulto , Anemia de Diamond-Blackfan/metabolismo , Anemia Macrocítica/metabolismo , Células da Medula Óssea/metabolismo , Criança , Deleção Cromossômica , Cromossomos Humanos Par 5/genética , Cromossomos Humanos Par 5/metabolismo , Ilhas de CpG , Feminino , Humanos , Fatores de Transcrição Kruppel-Like/biossíntese , Fatores de Transcrição Kruppel-Like/genética , Leucócitos Mononucleares/metabolismo , Masculino , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Proteína Proto-Oncogênica c-fli-1/biossíntese , Proteína Proto-Oncogênica c-fli-1/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/sangue , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Ribossômicas/fisiologia , Transcrição Gênica , Adulto Jovem
14.
Genes Chromosomes Cancer ; 51(5): 419-28, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22250017

RESUMO

Myelodysplastic syndrome (MDS), a clonal disorder originating from hematopoietic stem cell, is characterized by a progressive character often leading to transformation to acute myeloid leukemia. We used single nucleotide polymorphism arrays (SNP-A) to identify previously cryptic chromosomal abnormalities such as copy number alterations and uniparental disomies (UPD) in cytogenetically normal MDS. In the aberrant regions, we attempted to localize candidate genes with potential relevance to the disease. Using SNP-A, we analyzed peripheral blood granulocytes from 37 MDS patients. The analysis identified 13 cryptic chromosomal defects in 10 patients (27%). Four UPD (affecting chromosomes 3q, 7q, 17q, and 20p), 5 deletions and 4 duplications were detected. Gene expression data measured on CD34+ cells were available for 4 patients with and 6 patients without SNP-A lesions. We performed an integrative analysis of genotyping and gene expression microarrays and found several genes with an altered expression located in the aberrant regions. The expression microarrays suggested BMP2 and TRIB3 located in 20p UPD as potential candidate genes contributing to MDS. We showed that the genome-wide integrative approach is beneficial to the comprehension of molecular backgrounds of diseases with incompletely understood etiopathology.


Assuntos
Aberrações Cromossômicas , Perfilação da Expressão Gênica , Cariótipo , Síndromes Mielodisplásicas/genética , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/mortalidade , Reprodutibilidade dos Testes , Análise de Sobrevida , Adulto Jovem
15.
Blood ; 116(19): 3766-9, 2010 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-20802024

RESUMO

To identify cytogenetic risk factors predicting outcome in children with advanced myelodysplastic syndrome, overall survival of 192 children prospectively enrolled in European Working Group of Myelodysplastic Syndrome in Childhood studies was evaluated with regard to karyotypic complexity. Structurally complex constitutes a new definition of complex karyotype characterized by more than or equal to 3 chromosomal aberrations, including at least one structural aberration. Five-year overall survival in patients with more than or equal to 3 clonal aberrations, which were not structurally complex, did not differ from that observed in patients with normal karyotype. Cox regression analysis revealed the presence of a monosomal and structurally complex karyotype to be strongly associated with poor prognosis (hazard ratio = 4.6, P < .01). Notably, a structurally complex karyotype without a monosomy was associated with a very short 2-year overall survival probability of only 14% (hazard ratio = 14.5; P < .01). The presence of a structurally complex karyotype was the strongest independent prognostic marker predicting poor outcome in children with advanced myelodysplastic syndrome.


Assuntos
Síndromes Mielodisplásicas/genética , Adolescente , Anemia Refratária com Excesso de Blastos/genética , Anemia Refratária com Excesso de Blastos/mortalidade , Anemia Refratária com Excesso de Blastos/terapia , Criança , Aberrações Cromossômicas , Análise Citogenética , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Estimativa de Kaplan-Meier , Cariotipagem , Masculino , Monossomia , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/terapia , Prognóstico , Estudos Prospectivos , Fatores de Risco
16.
Haematologica ; 97(8): 1272-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22371180

RESUMO

The European Myeloma Network has organized two workshops on fluorescence in situ hybridization in multiple myeloma. The first aimed to identify specific indications and consensus technical approaches of current practice. A second workshop followed a quality control exercise in which 21 laboratories analyzed diagnostic cases of purified plasma cells for recurrent abnormalities. The summary report was discussed at the EHA Myeloma Scientific Working Group Meeting 2010. During the quality control exercise, there was acceptable agreement on more than 1,000 tests. The conclusions from the exercise were that the primary clinical applications for FISH analysis were for newly diagnosed cases of MM or frank relapse cases. A range of technical recommendations included: 1) material should be part of the first draw of the aspirate; 2) samples should be sent at suitable times to allow for the lengthy processing procedure; 3) most importantly, PCs must be purified or specifically identified; 4) positive cut-off levels should be relatively conservative: 10% for fusion or break-apart probes, 20% for numerical abnormalities; 5) informative probes should be combined to best effect; 6) in specialist laboratories, a single experienced analyst is considered adequate; 7) at least 100 PC should be scored; 8) essential abnormalities to test for are t(4;14), t(14;16) and 17p13 deletions; 9) suitable commercial probes should be available for clinically relevant abnormalities; 10) the clinical report should be expressed clearly and must state the percentage of PC involved and the method used for identification; 11) a retrospective European based FISH data bank linked to clinical data should be generated; and 12) prospective analysis should be centralized for upcoming trials based on the recommendations made. The European Myeloma Network aims to build on these recommendations to establish standards for a common European data base to define subgroups with prognostic significance.


Assuntos
Hibridização in Situ Fluorescente/normas , Mieloma Múltiplo/diagnóstico , Humanos , Hibridização in Situ Fluorescente/métodos , Guias de Prática Clínica como Assunto
17.
Eur J Haematol ; 88(2): 128-35, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21967546

RESUMO

OBJECTIVES: Recently, mutations in DNMT3A gene have been described in about 25% acute myeloid leukemia (AML) cases, preferentially in monocytic AML. They were found to predict worse overall survival (OS) of mutated patients. PATIENTS AND METHODS: RT-PCR followed by direct sequencing was used to test the presence of DNMT3A mutations in 226 AML patients with an intermediate-risk (IR) cytogenetics. RESULTS: Sixty-seven patients of 226 (29.6%) carried a mutation in the DNMT3A gene. Occurrence of DNMT3A mutations was associated with female sex (P = 0.027) and with the presence of FLT3/ITD (P = 0.003), but not with particular FAB subtypes. Patients with DNMT3A mutation had higher initial WBC counts than those without it (P = 0.064) only because of higher incidence of FLT3/ITD within these cases. There was no difference between mutated and wild-type groups in reaching complete remission (CR) (P = 0.380). OS was not affected by DNMT3A mutation (P = 0.251), but OS of patients who reached CR was longer in DNMT3A negative cases (P = 0.025). Patients with DNMT3A mutation had a higher relapse rate (P = 0.007). Patients carrying both the DNMT3A mutation and FLT3/ITD relapsed more often than either patients with single DNMT3A mutation (P = 0.044) or patients with FLT3/ITD only (P = 0.058). DNMT3A mutations were associated with higher relapse rate even within the FLT3/ITD-negative group (P = 0.072). After reaching CR, these two genetic factors were independent predictors of relapse at multivariate analysis (P < 0.001). Only three of 30 'double-mutated' (FLT3/ITD+, DNMT3A+) patients are still alive, all of them having undergone hematopoietic stem cell transplant. CONCLUSIONS: We have confirmed the high incidence of DNMT3A mutations in patients with AML with IR cytogenetics. Patients with DNMT3A mutations relapse more often and have inferior OS when only patients achieving CR are analyzed. 'Double-mutated' patients have a very poor prognosis.


Assuntos
Aberrações Cromossômicas , DNA (Citosina-5-)-Metiltransferases/genética , Leucemia Mieloide Aguda/genética , Mutação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Códon , DNA Metiltransferase 3A , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Indução de Remissão , Fatores de Risco , Adulto Jovem , Tirosina Quinase 3 Semelhante a fms/metabolismo
18.
Histochem Cell Biol ; 136(1): 93-101, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21695473

RESUMO

Posterior polymorphous corneal dystrophy (PPCD) is a rare, bilateral autosomal dominant disorder affecting primarily the corneal endothelium and descemet membrane (DM). The aim of this study was to establish the origin of abnormal endothelium in a patient with PPCD exhibiting cornea graft failure after keratoplasty surgery. A sex-mismatched graft obtained from a patient with PPCD who underwent repeat penetrating keratoplasty and the patient's original cornea were investigated. Combined fluorescent immunohistochemistry for cytokeratin (CK) 19 (a marker of aberrant PPCD endothelium) with fluorescence in situ hybridization (FISH) of the sex chromosomes were used in order to characterize the cells on the posterior graft surface. The pathological endothelium of the failed PPCD cornea revealed strong positivity for CK19 using fluorescent immunohistochemistry. In all the CK19-positive cells, both X and Y chromosomes were simultaneously detected using FISH. The results clearly showed the original cells of the patient (XY), within 3.5 years, almost totally overgrown the posterior corneal surface of the graft (XX). Moreover, an abnormal posterior collagenous layer populated by fibroblast-like cells was observed between DM and the endothelium in the failed graft, but its exact origin could not be established due to the low number of cells. Simultaneous detection of CK19 using fluorescent immunohistochemistry together with the detection of gonosomes using FISH was performed for the first time in the cornea and allowed us to prove that the recurrence of PPCD was caused by pathological abnormal proliferation and migration of recipient cells into donor graft.


Assuntos
Distrofias Hereditárias da Córnea/patologia , Endotélio Corneano/patologia , Cromossomos Humanos X , Cromossomos Humanos Y , Distrofias Hereditárias da Córnea/genética , Lâmina Limitante Posterior/patologia , Endotélio Corneano/citologia , Endotélio Corneano/metabolismo , Feminino , Humanos , Hibridização in Situ Fluorescente , Queratinas/metabolismo , Masculino , Pessoa de Meia-Idade
19.
Acta Haematol ; 126(3): 129-34, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21701158

RESUMO

Patients with near-tetraploid acute myeloid leukemia (NT-AML) typically have poor survival. We present the case of a 67-year-old Caucasian male with NT-AML M0 who had an unusually long first complete remission of 51 months and an overall survival of 80 months. The only characteristic distinguishing him from other previously described patients with NT-AML was the absence of erythroblastic and/or megakaryocytic dysplasia (EMD) at diagnosis. Molecular-genetic testing for AML fusion transcripts associated with a favorable prognosis (PML/RARα,AML1/ETO, and CBFß/MYH11) were negative, as were other prognostic markers like MLL-PTD,FLT3-ITD, or mutations of FLT3-D835,NPM1, or CEBPA. Expression studies of ERG,MN1, and EVI1 revealed overexpression of ERG only. The absence of EMD may be a useful prognostic/diagnostic feature of this new rare subtype of NT-AML.


Assuntos
Leucemia Mieloide Aguda/patologia , Análise de Sobrevida , Idoso , Humanos , Masculino , Nucleofosmina , Indução de Remissão
20.
Biol Blood Marrow Transplant ; 16(4): 548-54, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20005965

RESUMO

The prognostic significance of 1q21 gain, del(13)(q14), del(17)(p13), t(4;14)(p16.3;q32), and t(11;14)(q13;q32) detected by interphase fluorescein in situ hybridization (FISH) was studied in a cohort of 91 patients with newly diagnosed multiple myeloma (MM). 1q21 gain was detected in 37 of 91 patients (40.7%). In comparison with patients lacking 1q21 gain, patients with 1q21 gain had significantly shorter progression-free survival (PFS) (14.9 versus 27.4 months; P = .044) and worse 4-year overall survival (OS) (40.1% versus 76.2% of patients; P = <.001). PFS or OS were not influenced by the presence or absence of the other studied chromosomal abnormalities. Although the occurrence of 1q21 gain correlated with deletion of 13q14, the presence of 1q21 gain can be considered an independent prognostic factor, as no impact of del(13)(q14) as an isolated chromosomal abnormality on either PFS or OS has been observed. In comparison with patients lacking 1q21 gain, patients with 1q21 gain were significantly more likely to discontinue the preplanned treatment protocol because of disease progression or death. We conclude that 1q21 gain defines a prognostically unfavorable group of MM patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Aberrações Cromossômicas , Cromossomos Humanos Par 1 , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Adulto , Idoso , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida
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