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1.
Br J Haematol ; 174(2): 218-26, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27061303

RESUMO

Polycythaemia vera (PV), essential thrombocythaemia (ET) and primary myelofibrosis (PMF) represent typical myeloproliferative neoplasms (MPN), usually characterized by specific somatic driver mutations (JAK2 V617F, CALR and MPL). JAK2 46/1 haplotype and telomerase reverse transcriptase gene (TERT) rs2736100 A>C single nucleotide polymorphism (SNP) could represent a large fraction of the genetic predisposition seen in MPN. The rs10974944 C>G SNP, tagging the JAK2 46/1 haplotype, and the TERT rs2736100 A>C SNP were genotyped in 529 MPN patients with known JAK2 V617F, CALR and MPL status, and 433 controls. JAK2 46/1 haplotype strongly correlated to JAK2 V617F-positive MPN and, to a lesser extent, CALR-positive MPN. The TERT rs2736100 A>C SNP strongly correlated to all MPN, regardless of the phenotype (PV, ET or PMF) and major molecular subtype (JAK2 V617F- or CALR-positive). While both variants have a significant contribution, they have nuanced consequences, with JAK2 46/1 predisposing essentially to JAK2 V617F-positive MPN, and TERT rs2736100 A>C having a more general, non-specific effect on all MPN, regardless of phenotype or major molecular subtype.


Assuntos
Calreticulina/genética , Haplótipos/genética , Janus Quinase 2/genética , Transtornos Mieloproliferativos/genética , Telomerase/genética , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Fenótipo , Policitemia Vera/genética , Polimorfismo de Nucleotídeo Único , Mielofibrose Primária/genética , Trombocitemia Essencial/genética , Adulto Jovem
2.
Crit Rev Clin Lab Sci ; 52(5): 232-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26218036

RESUMO

The incidence of HIV-related lymphomas (HRLs) is increased by 60-100 times in patients with HIV. When compared to the general population, patients with HRLs often present with extranodal lymphoid proliferation, most frequently of the gastrointestinal tract, central nervous system, liver and bone marrow. MicroRNAs (miRs) are non-coding double-stranded RNA molecules of 18-25 nucleotides that regulate post-translational gene expression by inhibiting translation or promoting degradation of messenger RNA complementary sequences. Before their discovery, tumorigenesis was thought to have been caused by the alteration of protein-coding oncogenes and tumor-suppressor genes, but once identified in B-cell chronic lymphocytic leukemia, miRs function as either oncogenes or tumor-suppressor genes was confirmed in different types of malignancies. Since miRs are clearly involved in tumorigenesis in many cancers, their role in HRLs is now receiving attention. A few studies have been conducted thus far in some HRLs on the involvement of miR in the pathogenesis of lymphoid malignancies. Since B-cell lymphomas arise from various stages of B-cell development in both HIV-infected and HIV-naïve patients, investigators have tried to determine the different miR signatures in B-cell development. As classic immunohistochemistry staining is sometimes not enough for the differential diagnosis of HRLs, in the present review, we have described the potential use of miRs in the prognosis and diagnosis of these diseases.


Assuntos
Carcinogênese/metabolismo , Regulação Neoplásica da Expressão Gênica , Hospedeiro Imunocomprometido , Vigilância Imunológica , Linfoma Relacionado a AIDS/metabolismo , MicroRNAs/metabolismo , Modelos Biológicos , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Humanos , Linfoma Relacionado a AIDS/diagnóstico , Linfoma Relacionado a AIDS/etiologia , Linfoma Relacionado a AIDS/imunologia , Prognóstico , Microambiente Tumoral
3.
Ann Hematol ; 94(7): 1081-92, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25900787

RESUMO

Allogeneic hematopoietic stem cell transplantation (HCT) is a well-established treatment for many malignant and non-malignant hematological disorders. As frequent complication in up to 50 % of all patients, graft-versus-host disease (GVHD) is still the main cause for morbidity and non-relapse mortality. Diagnosis of GVHD is usually done clinically, even though confirmation by pathology is often used to support the clinical findings. Effective treatment requires intensified immunosuppression as early as possible. Although several promising biomarkers have been proposed for an early diagnosis, no internationally recognized consensus has yet been established. Here, microRNAs (miRs) represent an interesting tool since miRs have been recently reported to be an important regulator of various cells, including immune cells such as T cells. Therefore, we could assume that miRs play a key role in the pathogenesis of acute GVHD, and their detection might be an interesting possibility in the early diagnosis and monitoring of acute GVHD. Recent studies additionally demonstrated the implication of miRs in the pathogenesis of acute GVHD. In this review, we aim to summarize the previous reports of miRs, focusing on the pathogenesis of acute GVHD and possible implications in diagnostic approaches.


Assuntos
Doença Enxerto-Hospedeiro/metabolismo , MicroRNAs/biossíntese , Transplante de Células-Tronco/efeitos adversos , Animais , Biomarcadores/metabolismo , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/genética , Humanos , MicroRNAs/genética , Transplante de Células-Tronco/tendências , Transplante Homólogo/efeitos adversos , Transplante Homólogo/tendências
4.
Blood ; 120(18): 3670-6, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22915649

RESUMO

Rozrolimupab, a recombinant mixture of 25 fully human RhD-specific monoclonal antibodies, represents a new class of recombinant human antibody mixtures. In a phase 1 or 2 dose escalation study, RhD(+) patients (61 subjects) with primary immune thrombocytopenia received a single intravenous dose of rozrolimupab ranging from 75 to 300 µg/kg. The primary outcome was the occurrence of adverse events. The principal secondary outcome was the effect on platelet levels 7 days after the treatment. The most common adverse events were headache and pyrexia, mostly mild, and reported in 20% and 13% of the patients, respectively, without dose relationship. Rozrolimupab caused an expected transient reduction of hemoglobin concentration in the majority of the patients. At the dose of 300 µg/kg platelet responses, defined as platelet count ≥ 30 × 10(9)/L and an increase in platelet count by > 20 × 10(9)/L from baseline were observed after 72 hours and persisted for at least 7 days in 8 of 13 patients (62%). Platelet responses were observed within 24 hours in 23% of patients and lasted for a median of 14 days. Rozrolimupab was well tolerated and elicited rapid platelet responses in patients with immune thrombocytopenia and may be a useful alternative to plasma-derived products. This trial is registered at www.clinicaltrials.gov as #NCT00718692.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Imunoglobulina G/administração & dosagem , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Proteínas Recombinantes/administração & dosagem , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacocinética , Relação Dose-Resposta a Droga , Feminino , Humanos , Imunoglobulina G/efeitos adversos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/farmacocinética
5.
Ann Hematol ; 93(2): 203-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23828072

RESUMO

Arterial and venous thrombosis are the most frequent complications in patients with polycythemia vera and essential thrombocythemia. We sought to demonstrate a possible contribution of the factor V Leiden, prothrombin G20210A, and methylenetetrahydrofolate reductase (MTHFR) 677 C > T and 1298 A > C mutations to the thrombotic risk in patients with polycythemia vera and essential thrombocythemia along with other biological features of these patients. We included 86 patients with polycythemia vera, of which 34 (39.5 %) had major thrombosis and 95 patients with essential thrombocythemia, of which 22 (23.1 %) had major thrombosis. In the whole cohort of patients, only the factor V Leiden mutation was significantly associated with both arterial and venous thrombosis in univariate and multivariate analysis (odds ratio (OR) = 4.3; 95 % confidence interval (CI) = 1.5-12.5; p = 0.008 and OR = 4.3; 95 % CI = 1.2-15.9; p = 0.02, respectively). Other factors significantly associated with thrombosis in both univariate and multivariate analysis were male sex (OR = 2.8, 95 % CI = 1.4-5.4, p = 0.002 and OR = 3.5, 95 % CI = 1.6-7.6, p = 0.002, respectively) and the JAK2 V617F mutation (OR = 5.5, 95 % CI = 2.1-15, p = 0.0001 and OR = 6.9, 95 % CI = 2.2-21.2, p = 0.001, respectively). In conclusion, among the four mutations analyzed (factor V Leiden, prothrombin G20210A, and MTHFR 677 C > T and 1298 A > C), only factor V Leiden is a major contributor to thrombosis in polycythemia vera and essential thrombocythemia.


Assuntos
Fator V/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Mutação de Sentido Incorreto , Policitemia Vera/genética , Protrombina/genética , Trombocitemia Essencial/genética , Trombose/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Janus Quinase 2/genética , Masculino , Pessoa de Meia-Idade , Policitemia Vera/complicações , Estudos Retrospectivos , Fatores de Risco , Trombocitemia Essencial/complicações , Trombose/etiologia
8.
Ann Hematol ; 89(10): 979-83, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20422415

RESUMO

Polycythemia vera, essential thrombocythemia, and primary myelofibrosis are myeloproliferative neoplasms, characterized in a majority of cases by a unique somatic point mutation, JAK2 V617F. Recently, it was shown that JAK2 V617F occurs more frequently on a specific JAK2 haplotype, named JAK2 46/1. We genotyped 149 myeloproliferative neoplasms patients (69 had polycythemia vera, 65 had essential thrombocythemia, and 15 had primary myelofibrosis) with a known JAK2 V617F mutational status and 150 controls for the JAK2 rs10974944 (C/G) single nucleotide polymorphism, in which the G allele tags the 46/1 haplotype. We found that the rs10974944 GG/CG genotypes were significantly enriched in patients compared to controls (p < 0.0001). After stratifying for the JAK2 V617F mutational status and for the mutant allele burden, we demonstrated that GG/CG genotypes were significantly more frequent in V617F positive compared to V617F negative patients (p = 0.001), but not in V617F negative patients compared to controls (p = 0.29). Similarly, the GG/CG genotypes were significantly enriched in V617F positive patients with a mutant allele burden >50% compared to those with a mutant allele burden <50% (p = 0.0006). Our results indicate that the G allele, part of the JAK2 46/1 haplotype, contributes significantly to the occurrence of JAK2 V617F-positive myeloproliferative neoplasms. Moreover, JAK2 46/1 seems to be associated with mutant allele burden >50% in JAK2 V617F-positive myeloproliferative neoplasms patients.


Assuntos
Alelos , Haplótipos , Neoplasias Hematológicas , Janus Quinase 2/genética , Transtornos Mieloproliferativos , Polimorfismo de Nucleotídeo Único , Genótipo , Neoplasias Hematológicas/enzimologia , Neoplasias Hematológicas/genética , Humanos , Pessoa de Meia-Idade , Mutação , Transtornos Mieloproliferativos/enzimologia , Transtornos Mieloproliferativos/genética
11.
Med Hypotheses ; 66(2): 352-4, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16226391

RESUMO

Multiple myeloma (MM) is a B cell lymphoproliferative disorder in which malignant plasma cells accumulate in the bone marrow and usually produce monoclonal immunoglobulin in excess. Interleukin-6 (IL-6), is known to be an essential survival factor of myeloma cells, high IL-6 levels being correlated with an adverse prognosis. IL-6 modulates the transcription of several liver-specific acute phase protein genes, including C-reactive protein and hepcidin. Anemia is one of the prominent features of MM, along with recurrent osteolytic lesions, bacterial infections and renal insufficiency. The current treatment strategies of MM related anemia are often inadequate and many patients rely on transfusions. Several causes have been implicated, but anemia of chronic disease (ACD) related to the inflammatory cytokines appears to be one of the main culprits. The pathogenesis of ACD had been poorly understood, but recently it has been shown that increased Il-6 upregulates the hepatic production of hepcidin, which, by binding to its cellular receptor, ferroportin, causes anemia by blocking iron export from enterocytes and macrophages. We hereby argue that by virtue of its biological characteristics, multiple myeloma should be an ideal clinical setting to test the role of hepcidin in the pathogenesis of ACD. Hepcidin levels should be higher in MM patients and might correlate with prognosis. Anemic MM patients should also be among those who would benefit mostly from hepcidin targeted therapies.


Assuntos
Anemia/fisiopatologia , Peptídeos Catiônicos Antimicrobianos/fisiologia , Mieloma Múltiplo/fisiopatologia , Anemia/complicações , Hepcidinas , Humanos , Interleucina-6/fisiologia , Mieloma Múltiplo/complicações
12.
Int J Nanomedicine ; 11: 641-60, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26929621

RESUMO

BACKGROUND AND AIMS: Every year, in Europe, acute myeloid leukemia (AML) is diagnosed in thousands of adults. For most subtypes of AML, the backbone of treatment was introduced nearly 40 years ago as a combination of cytosine arabinoside with an anthracycline. This therapy is still the worldwide standard of care. Two-thirds of patients achieve complete remission, although most of them ultimately relapse. Since the FLT3 mutation is the most frequent, it serves as a key molecular target for tyrosine kinase inhibitors (TKIs) that inhibit FLT3 kinase. In this study, we report the conjugation of TKIs onto spherical gold nanoparticles. MATERIALS AND METHODS: The internalization of TKI-nanocarriers was proved by the strongly scattered light from gold nanoparticles and was correlated with the results obtained by transmission electron microscopy and dark-field microscopy. The therapeutic effect of the newly designed drugs was investigated by several methods including cell counting assay as well as the MTT assay. RESULTS: We report the newly described bioconjugates to be superior when compared with the drug alone, with data confirmed by state-of-the-art analyses of internalization, cell biology, gene analysis for FLT3-IDT gene, and Western blotting to assess degradation of the FLT3 protein. CONCLUSION: The effective transmembrane delivery and increased efficacy validate its use as a potential therapeutic.


Assuntos
Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Ouro/química , Leucemia Mieloide Aguda/tratamento farmacológico , Nanopartículas Metálicas/química , Inibidores de Proteínas Quinases/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Proliferação de Células/efeitos dos fármacos , Ouro/administração & dosagem , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Nanopartículas Metálicas/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/química , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo
15.
Med Hypotheses ; 65(1): 107-13, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15893127

RESUMO

Despite the common clinical, hematological and prognostic features that define acute myeloid leukemia (AML) there is considerable heterogeneity among individual cases, suggesting different pathogenic pathways. Based on a simple theoretical model, according to the vital characteristics of the leukemic clone (proliferative rate and resistance to apoptosis), I propose a classification of AML into two broad categories: (a) high leukemic clone vitality (HLV) AML or "dominant type" AML, corresponding roughly to the World Health Organization (WHO) classification group of entities "AML with recurrent cytogenetic abnormalities" and (b) low leukemic clone vitality (LLV) or "opportunistic type" AML corresponding to the WHO groups "AML with multilineage dysplasia" and "alkylating agent-related AML". HLV-AML leukemic clones are characterized by rate-limiting genomic mutations capable of conferring proliferation/survival advantage over a normal hematopoietic environment while in LLV-AML, the leukemic clones are not particularly proliferative or apoptosis-resistant, but are nevertheless selected against an impaired, previously damaged hematopoietic environment. Such a pathogenesis-oriented classification might have therapeutic and prognostic implications, providing a theoretical basis for a further adaptation of the current standard treatment strategies to the individual characteristics of the AML patients.


Assuntos
Células Clonais , Leucemia Mieloide Aguda/classificação , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/etiologia , Apoptose , Linhagem da Célula , Proliferação de Células , Análise Citogenética , Humanos , Cinética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/fisiopatologia , Leucemia Mieloide Aguda/terapia , Modelos Biológicos , Mutação , Prognóstico , Seleção Genética , Análise de Sobrevida , Organização Mundial da Saúde
16.
Rom J Gastroenterol ; 14(3): 273-8, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16200239

RESUMO

Primary gastrointestinal non-Hodgkin lymphoma accounts for 13-18% of all malignant tumours of small bowel and only 1 % of large bowel tumours (1). Multiple lymphomatous polyposis is a rare entity, characterized by the presence of multiple lymphomatous polyps along the gut (2). Majority of cases with gastrointestinal primary lymphoma are classified histologically as "mantle cell" lymphomas. A 59 year old patient was admitted to our clinic for fatigue and rectal bleeding. Endoscopic examination of the colon revealed an infiltrative-exulcerative lesion of the terminal ileon, a polypoid mass on ileocecal valve and multiple polyps over the entire colon and rectum. Gastroscopy revealed polyps into the duodenal bulb. Histopathological and immunohistochemical studies on biopsy specimens from colon and duodenum confirmed gastrointestinal non-Hodgkin lymphoma, probably "mantle cell" lymphoma. Because she was in an advanced stage she received only cytostatic treatment. A clinical, endoscopical and histopathological follow up at 3, 6 and 12 months was performed.


Assuntos
Pólipos Intestinais/patologia , Linfoma de Célula do Manto/patologia , Colonoscopia , Feminino , Gastroscopia , Humanos , Pólipos Intestinais/etiologia , Linfoma de Célula do Manto/complicações , Pessoa de Meia-Idade , Prognóstico
17.
Exp Hematol ; 43(3): 158-67, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25462020

RESUMO

Multiple myeloma (MM) is a hematologic malignancy characterized as an abnormal proliferation and invasion of plasma cells into the bone marrow. Toll-like receptors (ТLRs) connect the innate and adaptive immune responses and represent a significant and potentially linking element between inflammation and cancer. When TLRs bind to their ligands, they trigger two major signaling pathways such that both share overlapping downstream signals: one is a myeloid differentiation primary response 88 (MyD88)-dependent production and activation of nuclear factor-κB, whereas the other is a MyD88-independent production of type-I interferon. Whereas the MyD88 pathway results in proinflammatory cytokine production, the other pathway stimulates cell proliferation. Dysregulations of these pathways may eventually lead to abnormal cell proliferation and MM. Despite recent biomedical advances, MM continues to be an incurable disease. There are an increasing number of TLR-based therapeutic approaches currently being tested in a number of preclinical and clinical studies. We here attempt to outline in detail the currently available information on TLRs in various types of cancer.


Assuntos
Mieloma Múltiplo/fisiopatologia , Receptores Toll-Like/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos/tendências , Humanos , Mieloma Múltiplo/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos
18.
Case Rep Hematol ; 2014: 841787, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25525531

RESUMO

Familial essential thrombocythemia features the acquisition of somatic mutations and an evolution similar to the sporadic form of the disease. Here we report two patients-father and daughter-with essential thrombocythemia who displayed a heterogeneous pattern of somatic mutations. The JAK2 V617F mutation was found in the daughter, while the father harbored the MPL W515L mutation. This case report may constitute further proof that in familial essential thrombocythemia there are other, still undefined, constitutional, inherited genetic factors predisposing to the acquisition of various somatic mutations (e.g., JAK2 V617F and MPL).

19.
Rom J Morphol Embryol ; 55(1): 23-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24715161

RESUMO

Diagnosis of myeloid malignancies with erythroid hyperplasia may sometimes confront hematologists with a mathematical dilemma, if cut-off criteria of blast percentage as proposed by the World Health Organization (WHO) 2008 Classification are applied. Several questions have been raised regarding differentiation of acute erythroid leukemia (AEL) from myelodysplastic syndrome with erythroid hyperplasia and some aspects still remain unclear. This paper discusses the differential diagnosis and presents our own experience in a series of patients with acute myeloid leukemia. Although the diagnostic criteria of AEL have been repeatedly refined, it remains a diagnosis primarily based on morphology and on exclusion criteria. Many of the cases designated before 2001 as AEL, actually fit into other disease categories, most often into myelodysplasia related changes - acute myeloid leukemia.


Assuntos
Células Eritroides/patologia , Leucemia Mieloide Aguda/patologia , Adulto , Idoso , Células da Medula Óssea/patologia , Contagem de Células , Núcleo Celular/patologia , Diagnóstico Diferencial , Feminino , Humanos , Hiperplasia , Imunofenotipagem , Cariotipagem , Leucemia Mieloide Aguda/diagnóstico , Masculino , Pessoa de Meia-Idade
20.
Clujul Med ; 87(3): 192-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26528023

RESUMO

BACKGROUND AND AIMS: Castleman's disease is a rare disorder situated at the boundary between reactive and neoplastic conditions. The pathogenesis is a subject of debate and the limited number of cases renders the study of the disease difficult. In our paper we present a series of six cases of Castleman disease with emphasis on the clinical presentation, pathology examination and the use of immunohistochemistry in the final diagnosis of the cases. PATIENTS AND METHOD: The classification of the disease was based on clinical, imaging and pathological assessment. Specimens were obtained by surgical excision and were routinely processed for the pathology examination. RESULTS: All cases were unicentric disease. Two cases were locally extensive. The clinical symptoms were related mostly to compression effects. Five case were of the hyaline-vascular type and one was included in the plasma cell variant. One case showed angiomyoid differentiation. CONCLUSIONS: We strongly believe that by understanding the pathogenesis of the precursor lesions we will gain better understanding of the pathways that lead to neoplasia and that Castleman disesase is a very interesting "natural experiment" illustrating the progression from chronic antigen stimulation to reactive lymphoid hyperplasia and finally to overt lymphoid neoplasia.

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