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1.
Am J Hematol ; 98(2): 264-271, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36588407

RESUMO

Familial forms of monoclonal gammopathy, defined as multiple myeloma (MM) or Monoclonal Gammopathy of Undetermined Significance (MGUS), are relatively infrequent and most series reported in the literature describe a limited number of families. MM rarely occurs in a familial context. MGUS is observed much more commonly, which can in some cases evolve toward full-blown MM. Although recurrent cytogenetic abnormalities have been described in tumor cells of sporadic cases of MM, the pathogenesis of familial MM remains largely unexplained. In order to identify genetic factors predisposing to familial monoclonal gammopathy, the Intergroupe Francophone du Myélome identified 318 families with at least two confirmed cases of monoclonal gammopathy. There were 169 families with parent/child pairs and 164 families with cases in at least two siblings, compatible with an autosomal transmission. These familial cases were compared with sporadic cases who were matched for age at diagnosis, sex and immunoglobulin isotype, with 10 sporadic cases for each familial case. The gender distribution, age and immunoglobulin subtypes of familial cases were unremarkable in comparison to sporadic cases. With a median follow-up of 7.4 years after diagnosis, the percentage of MGUS cases having evolved to MM was 3%. The median overall survival of the 148 familial MM cases was longer than that of matched sporadic cases, with projected values of 7.6 and 16.1 years in patients older and younger than 65 years, respectively. These data suggest that familial cases of monoclonal gammopathy are similar to sporadic cases in terms of clinical presentation and carry a better prognosis.


Assuntos
Gamopatia Monoclonal de Significância Indeterminada , Mieloma Múltiplo , Paraproteinemias , Criança , Humanos , Gamopatia Monoclonal de Significância Indeterminada/diagnóstico , Paraproteinemias/genética , Paraproteinemias/complicações , Mieloma Múltiplo/patologia , Prognóstico , Aberrações Cromossômicas
2.
Cancer Gene Ther ; 29(8-9): 1263-1275, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35194200

RESUMO

DNA methylation, a major biological process regulating the transcription, contributes to the pathophysiology of hematologic malignancies, and hypomethylating agents are commonly used to treat myelodysplastic syndromes (MDS) and acute myeloid leukemias (AML). In these diseases, bone marrow mesenchymal stromal cells (MSCs) play a key supportive role through the production of various signals and interactions. The DNA methylation status of MSCs, likely to reflect their functionality, might be relevant to understand their contribution to the pathophysiology of these diseases. Consequently, the aim of our study was to analyze the modifications of DNA methylation profiles of MSCs induced by MDS or AML. MSCs from MDS/AML patients were characterized via 5-methylcytosine quantification, gene expression profiles of key regulators of DNA methylation, identification of differentially methylated regions (DMRs) by methylome array, and quantification of DMR-coupled genes expression. MDS and AML-MSCs displayed global hypomethylation and under-expression of DNMT1 and UHRF1. Methylome analysis revealed aberrant methylation profiles in all MDS and in a subgroup of AML-MSCs. This aberrant methylation was preferentially found in the sequence of homeobox genes, especially from the HOX family (HOXA1, HOXA4, HOXA5, HOXA9, HOXA10, HOXA11, HOXB5, HOXC4, and HOXC6), and impacted on their expression. These results highlight modifications of DNA methylation in MDS/AML-MSCs, both at global and focal levels dysregulating the expression of HOX genes well known for their involvement in leukemogenesis. Such DNA methylation in MSCs could be the consequence of the malignant disease or could participate in its development through defective functionality or exosomal transfer of HOX transcription factors from MSCs to hematopoietic cells.


Assuntos
Leucemia Mieloide Aguda , Células-Tronco Mesenquimais , Síndromes Mielodisplásicas , Medula Óssea/patologia , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Metilação de DNA , Genes Homeobox/genética , Humanos , Leucemia Mieloide Aguda/patologia , Células-Tronco Mesenquimais/metabolismo , Síndromes Mielodisplásicas/genética , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/metabolismo
3.
Haematologica ; 95(8): 1278-86, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20179084

RESUMO

BACKGROUND: Protein 4.2 deficiency caused by mutations in the EPB42 gene results in hereditary spherocytosis with characteristic alterations of CD47, CD44 and RhAG. We decided to investigate at which stage of erythropoiesis these hallmarks of protein 4.2 deficiency arise in a novel protein 4.2 patient and whether they cause disruption to the band 3 macrocomplex. DESIGN AND METHODS: We used immunoprecipitations and detergent extractability to assess the strength of protein associations within the band 3 macrocomplex and with the cytoskeleton in erythrocytes. Patient erythroblasts were cultured from peripheral blood mononuclear cells to study the effects of protein 4.2 deficiency during erythropoiesis. RESULTS: We report a patient with two novel mutations in EPB42 resulting in complete protein 4.2 deficiency. Immunoprecipitations revealed a weakened ankyrin-1-band 3 interaction in erythrocytes resulting in increased band 3 detergent extractability. CD44 abundance and its association with the cytoskeleton were increased. Erythroblast differentiation revealed that protein 4.2 and band 3 appear simultaneously and associate early in differentiation. Protein 4.2 deficiency results in lower CD47, higher CD44 expression and increased RhAG glycosylation starting from the basophilic stage. The normal downregulation of CD44 expression was not seen during protein 4.2(-) erythroblast differentiation. Knockdown of CD47 did not increase CD44 expression, arguing against a direct reciprocal relationship. CONCLUSIONS: We have established that the characteristic changes caused by protein 4.2 deficiency occur early during erythropoiesis. We postulate that weakening of the ankyrin-1-band 3 association during protein 4.2 deficiency is compensated, in part, by increased CD44-cytoskeleton binding.


Assuntos
Proteínas do Citoesqueleto/deficiência , Membrana Eritrocítica/metabolismo , Eritropoese , Proteínas de Membrana/metabolismo , Adulto , Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Anquirinas/metabolismo , Sequência de Bases , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Antígeno CD47/genética , Antígeno CD47/metabolismo , Diferenciação Celular , Células Cultivadas , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Citoesqueleto/metabolismo , Eritroblastos/citologia , Eritroblastos/metabolismo , Humanos , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Immunoblotting , Imunoprecipitação , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Dados de Sequência Molecular , Mutação , Ligação Proteica , Homologia de Sequência do Ácido Nucleico
4.
Haematologica ; 91(8): 1027-32, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16885042

RESUMO

BACKGROUND AND OBJECTIVES: In non-randomized studies, thalidomide appeared to be effective in myeloid metaplasia with myelofibrosis (MMM). We compared thalidomide to placebo for treatment of anemia in MMM. DESIGN AND METHODS: A prospective phase II B, randomized double-blind multicenter trial comparing thalidomide 400 mg/d with placebo for 180 days was conducted in 52 anemic patients (hemoglobin pounds Sterling 9 g/dL or transfused). The main outcome measure was a 2 g/L increase in hemoglobin or 20% reduction in transfusions. RESULTS: In the thalidomide group only 10 patients completed 6 months of treatment. At 180 days, in an intention-to-treat analysis, no difference was observed between the thalidomide and placebo groups as regards improvement of hemoglobin levels (one patient in each group) or reduction of red blood cell transfusions (three vs five patients, respectively). The spleen size, determined by ultrasonography, increased significantly less in the thalidomide group than in the placebo group (p < 0.05). Thalidomide had no apparent benefit on the Dupriez score, the severity score, survival, death, or any other clinical or biological parameter. Somnolence, gastro-intestinal signs, weight gain, and edema were significantly more frequent in the thalidomide group. Outpatient discontinuation of thalidomide was significantly correlated with a high severity score > 4 (odds ratio, OR = 16; p < 0.01), and g-glutamyl transferase levels > 40 IU/L (OR = 12; p < 0.05). INTERPRETATION AND CONCLUSIONS: Thalidomide (200-400 mg/d) does not demonstrate substantial efficacy in anemic MMM patients. The natural history of disease in the placebo group revealed spontaneous periods of remission of anemia. Tolerance of thalidomide was significantly correlated wih the severity and liver involvement of the disease.


Assuntos
Mielofibrose Primária/complicações , Mielofibrose Primária/tratamento farmacológico , Talidomida/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Método Duplo-Cego , França , Humanos , Placebos , Reprodutibilidade dos Testes , Projetos de Pesquisa , Talidomida/toxicidade
6.
Clin Cancer Res ; 19(17): 4634-7, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23857603

RESUMO

PURPOSE: Although the translocation t(4;14) is supposed to be a primary event in multiple myeloma, we have been surprised to observe that in large relapse series of patients, the t(4;14) can be observed only in subpopulations of plasma cells, in contrast to what is seen at diagnosis. This observation raised the question of possible subclones harboring the translocation that would be observable only at the time of relapse. EXPERIMENTAL DESIGN: To address this issue, we analyzed by FISH a cohort of 306 patients for whom we had at least two samples obtained at different disease phases. RESULTS: We observed a "gain" of the t(4;14) in 14 patients, and conversely, a "loss" of the translocation in 11 patients. Two hypotheses were raised: either an acquisition of the translocation during evolution or the existence of small t(4;14)-positive subclones at the time of diagnosis. To address this question, we had the opportunity to analyze two patients at the time of diagnosis by RT-PCR (reverse transcription-polymerase chain reaction) to look for the chimeric Eµ-MMSET transcript, and one patient positive at diagnosis, but negative at relapse. The samples were positive, supporting the second hypothesis. Furthermore, the IGH sequences of two patients who "lose" the t(4;14) were identical at diagnosis and relapse, confirming the existence of a common ancestral clone. CONCLUSION: Thus, the conclusion of this study is that the t(4;14) is not a primary event in multiple myeloma and that it can be present in silent subclones at diagnosis, but also at relapse.


Assuntos
Mieloma Múltiplo/genética , Recidiva Local de Neoplasia/genética , Proteínas de Fusão Oncogênica/genética , Translocação Genética , Idoso , Sequência de Bases , Linhagem da Célula , Cromossomos Humanos Par 14/genética , Cromossomos Humanos Par 4/genética , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Recidiva Local de Neoplasia/patologia , Proteínas de Fusão Oncogênica/isolamento & purificação
7.
Bull Cancer ; 93 Suppl 1: S5-9, 2006 Feb 01.
Artigo em Francês | MEDLINE | ID: mdl-16483940

RESUMO

Oxaliplatin in combination with 5-fluorouracil/leucovorin (LV5FU) improves the response rate and survival of patients with metastatic colorectal cancer. The objective of the Mosaic study was to evaluate the efficacy of this association in the adjuvant treatment of stage II and III colon cancer. This international study, including 2,246 patients, compared the efficacy of standard treatment with LV5FU2 alone to that of oxaliplatin-LV5FU (Folfox4 regimen) following R0 resection of the primary tumour. Both treatments were administered every two weeks for six months. At 3-year follow-up, the risk of relapse was decreased by 23% in the Folfox4 group (p = 0.002). The protocol was well tolerated, with an identical overall mortality during treatment (0.5%) in both groups. The main specific complication, peripheral sensory neuropathy was reversible in the great majority of cases. A new analysis at 4-year follow-up (median 48.6 months) confirmed the superior efficacy of the Folfox4 regimen compared to the standard treatment, the reduction in relapse risk being 24% (p = 0.0008). On the strength of these results, oxaliplatin was granted a marketing authorization for the indication adjuvant treatment of stage III colon cancer. Based on the data currently available, physicians should consider adjuvant treatment for stage II patients, making each individual decision for treatment on a case-by-case basis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Quimioterapia Adjuvante , Ensaios Clínicos como Assunto , Fluoruracila/uso terapêutico , Humanos , Leucovorina/uso terapêutico , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina
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