RESUMO
BACKGROUND: Chronic myeloid leukemia (CML) is a hematological disorder that in rare cases, mainly in CML neutrophilic, presents the e19a2 rearrangement. The encoded product is a 230-KDa protein. Despite the remarkable responses to treatment of most patients, a small but significant fraction of them develop clinical resistance to the tyrosine kinase inhibitors (TKIs). The most common mechanism of resistance is point mutations in the ABL1 kinase domain. The recently approved third-generation TKI ponatinib demonstrated remarkable activity in patients with multi-TKI-resistant disease. Particularly impressive was its efficacy in patients with T315I mutation that is resistant to all other TKIs. METHODS: Qualitative PCR was carried out by multiplex approach. Relative transcripts quantification was performed by one-step real-time PCR, with a specific Taqman probe and primers for the e19a2 rearrangement. We carried out a mutational screening by high-resolution melting, and the mutation was identified by Sanger method. The mutation burden was quantified by quantitative PCR using allele-specific primers. RESULTS: In a patient with CML, we identified a PCR product corresponding to e19a2 rearrangement harboring T315I mutation. At the time of mutational analysis, during dasatinib treatment, the T315I clone was 100% and the quantification of BCR-ABL1 was 18%. After ponatinib therapy, the T315I mutation burden decreased down to undetectable levels and the BCR-ABL1 transcripts showed a very low value (0.011%). CONCLUSIONS: Here, we report the hematological, cytogenetic, and molecular response of a patient with refractory CML in chronic phase with e19a2 transcripts, carrying T315I mutation that was successfully treated with ponatinib.
Assuntos
Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Imidazóis/uso terapêutico , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Piridazinas/uso terapêutico , RNA Mensageiro/antagonistas & inibidores , Dasatinibe , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Expressão Gênica , Humanos , Hidroxiureia/uso terapêutico , Leucemia Mieloide de Fase Crônica/genética , Leucemia Mieloide de Fase Crônica/patologia , Pessoa de Meia-Idade , Mutação , Pirimidinas/uso terapêutico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Tiazóis/uso terapêutico , Resultado do TratamentoRESUMO
En la medicina popular se utiliza el leño de Picrasma crenata en infusión como pediculicida y como tónico amargo no astringente. Los principios activos responsables de la actividad son los quasinoides. Los objetivos de este trabajo son: determinar la actividad de las infusiones sobre el desarrollo de raíces y la división celular mediante el Test de Allium cepa; analizar la correlación de las concentraciones y los parámetros macro y microscópicos e interpretar la posible genotoxicidad de la infusión. Las concentraciones empleadas fueron 2,5 mg%; 5,0 mg%, 10,0 mg%, 20,0 mg% y 40,0 mg%. Se observó una correlación estadísticamente significativa de las concentraciones con las longitudes de las raíces y las anomalías macroscópicas; además, una correlación significativa de los índices mitóticos con las longitudes de las raíces y las anomalías microscópicas. Así, se puede inferir que los extractos en las concentraciones ensayadas podrían presentar actividad genotóxica.
Infusions of Picrasma crenata woods are used in folk medicine against lice and as a non astringent bitter tonic. The active principles responsible for the activity are the quasinoides. The objectives of this work are: to establish the activity of the infusions on the development by roots and the cellular division by means of the Test of Allium cepa; to analyze the correlation of the concentrations with macro and microscopic parameters and to conclude about the possible genotoxicity of the infusion. The used concentrations were 2.5 mg%; 5,0 mg%, 10,0 mg%, 20,0 mg% and 40,0 mg%. A statistically significant correlation between the concentrations and the roots lengths and macroscopic aberrations and a significant correlation between the mitotic index and the roots lengths and microscopic aberrations have been observed. Thus, it is possible to deduce that the extracts in the tested concentrations could present genotoxic activity.
Assuntos
Cebolas/genética , Picrasma/genética , Picrasma/toxicidade , Argentina , Medicina Tradicional , Preparações de Plantas/toxicidadeRESUMO
OBJECTIVES: Diffuse large B-cell lymphoma (DLBCL) is the most common form of non-Hodgkin lymphomas. Cytogenetic studies have revealed a broad spectrum of clonal genetic abnormalities and complex karyotypes. The purpose of this study was to contribute to the understanding of the genomic alterations associated with this group of lymphomas. METHODS: Cytogenetic, fluorescence in situ hybridization (FISH) and molecular analyses were performed in 30 cases with DLBCL: 20 de novo DLBCL (dn-DLBCL) and 10 DLBCL secondary to follicular lymphoma (S-DLBCL). RESULTS: A total of 37 different structural chromosomal rearrangements were found: 27% translocations, 54% deletions, and 19% other alterations. Chromosomes 8, 6, 2, and 9 were the most commonly affected. Interestingly, translocation t(3;14)(q27;q32) and/or BCL-6 gene rearrangements were not observed either by cytogenetic studies or by FISH analysis. Fifteen novel cytogenetic alterations were detected, among them translocations t(2;21)(p11;q22) and t(8;18)(q24;p11.3) appeared as sole structural abnormalities. Translocation t(14;18)(q32;q21) and/or BCL-2-IGH gene rearrangements were the genomic alterations most frequently observed: 50% of S-DLBCL and 30% of dn-DLBCL. Deletions del(4)(q21), del(6)(q27), del(8)(q11), and del(9)(q11) were recurrent. The most common gains involved chromosome regions at 12q13-q24, 7q10-q32, and 17q22-qter; 6q was the most frequently deleted region, followed by losses at 2q35-qter, 7q32-qter, and 9q13-qter. Four novel regions of loss were identified: 5q13-q21, 2q35-qter (both recurrent in our series), 4p11-p12, and 17q11-q12. CONCLUSIONS: These studies emphasize the value of combining conventional cytogenetics with FISH and molecular studies to allow a more accurate definition of the genomic aberrations involved in DLBCL.
Assuntos
Cromossomos Humanos/genética , Linfoma de Células B/genética , Linfoma Folicular/genética , Linfoma Difuso de Grandes Células B/genética , Segunda Neoplasia Primária/genética , Translocação Genética/genética , Adolescente , Adulto , Idoso , Argentina , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Hibridização in Situ Fluorescente/métodos , Cariotipagem , Linfoma de Células B/patologia , Linfoma Folicular/patologia , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Segunda Neoplasia Primária/patologia , Proteínas Proto-Oncogênicas c-bcl-6 , Deleção de Sequência/genéticaRESUMO
Telomeres are essential for maintaining chromosomal integrity and stability. We studied here telomere length (TL) in bone marrow and/or lymph node from 36 patients: 29 with follicular lymphoma (FL) at diagnosis and 7 with diffuse large B cell lymphoma secondary to FL (S-DLBCL). TL was evaluated using terminal restriction fragments (TRF) assay. BCL-2 gene rearrangement was analyzed by nested and long distance PCR. Mean TRF values showed significant telomere shortening in FL (4.18 +/- 0.18 Kb) and S-DLBCL (3.31 +/- 0.25 Kb) respect to controls (8.50 +/- 0.50 Kb) (p<0.001). Differences between both histological subtypes (p=0.036) were also detected. Moreover, the samples positive for BCL-2 rearrangements showed longer TL (4.25 +/- 0.19 Kb) than the negative ones (3.39 +/- 0.30 Kb) (p=0.023). A trend to telomere shortening was observed when Major Breakpoint Region (MBR-JH), minor cluster region (mcr-JH) and BCL-2 negative patients were compared (4.35 +/- 0.21 Kb; 3.84 +/- 0.45 Kb and 3.39 +/- 0.30 Kb, respectively). Our results show a TL reduction in FL and S-DLBCL, with significant short TRFs in the last group, suggesting the participation of telomere shortening in tumor progression. Furthermore, the differences detected between BCL-2 positive and negative FL support the involvement of diverse pathogenic mechanisms.
Assuntos
Linfoma de Células B/genética , Linfoma Folicular/genética , Linfoma Difuso de Grandes Células B/genética , Telômero/fisiologia , Adulto , Idoso , Medula Óssea/patologia , Feminino , Gânglios/patologia , Genes bcl-2/genética , Humanos , Masculino , Pessoa de Meia-Idade , Telômero/genéticaRESUMO
Telomeres are essential for maintaining chromosomal integrity and stability. We studied here telomere length (TL) in bone marrow and/or lymph node from 36 patients: 29 with follicular lymphoma (FL) at diagnosis and 7 with diffuse large B cell lymphoma secondary to FL (S-DLBCL). TL was evaluated using terminal restriction fragments (TRF) assay. BCL-2 gene rearrangement was analyzed by nested and long distance PCR. Mean TRF values showed significant telomere shortening in FL (4.18 +/- 0.18 Kb) and S-DLBCL (3.31 +/- 0.25 Kb) respect to controls (8.50 +/- 0.50 Kb) (p<0.001). Differences between both histological subtypes (p=0.036) were also detected. Moreover, the samples positive for BCL-2 rearrangements showed longer TL (4.25 +/- 0.19 Kb) than the negative ones (3.39 +/- 0.30 Kb) (p=0.023). A trend to telomere shortening was observed when Major Breakpoint Region (MBR-JH), minor cluster region (mcr-JH) and BCL-2 negative patients were compared (4.35 +/- 0.21 Kb; 3.84 +/- 0.45 Kb and 3.39 +/- 0.30 Kb, respectively). Our results show a TL reduction in FL and S-DLBCL, with significant short TRFs in the last group, suggesting the participation of telomere shortening in tumor progression. Furthermore, the differences detected between BCL-2 positive and negative FL support the involvement of diverse pathogenic mechanisms.
