Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
BMC Cancer ; 22(1): 1024, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36175852

RESUMO

BACKGROUND: Telomere dysfunction results in aneuploidy, and ongoing chromosomal abnormalities. The three-dimensional (3D) nuclear organization of telomeres allows for a distinction between normal and tumor cells. On the other hand, aurora kinase genes (AURKA and AURKB) play an important role regulating the cell cycle. A correlation between overexpression of aurora kinase genes and clinical aggressiveness has been demonstrated in different types of neoplasias. To better understand cellular and molecular mechanisms of CML evolution, it was examined telomere dysfunction (alterations in the 3D nuclear telomere architecture), and the expression levels of AURKA and AURKB genes in two clinical distinct subgroups of CML samples, from the same patient. METHODS: Eighteen CML patients, in total, 36 bone marrow samples (18 patients, chronic vs. accelerated/blast phase) were eligible for 3D telomeric investigations. Quantitative 3D imaging, cytologic diagnosis and cytogenetic determination of additional chromosomal abnormalities were assessed according to standard protocols. RESULTS: Using TeloView software, two CML subgroups were defined based on their 3D telomeric profiles, reflecting the different stages of the disease (chronic vs. accelerated/blast phase). Statistical analyses showed significant differences between the CML subgroups (p < 0.001). We also found that AURKA and AURKB mRNA were expressed at significantly higher levels in both CML subgroups, when compared with healthy donors. Our findings suggest that the evolution of CML progresses from a low to a high level of telomere dysfunction, that is, from an early stage to a more aggressive stage, followed by disease transformation, as demonstrated by telomere, additional chromosomal abnormalities, and gene expression profile dynamics. CONCLUSIONS: Thus, we demonstrated that 3D telomere organization, in accordance with the genomic instability observed in CML samples were able to distinguish subgroup CML patients. Classifying CML patients based on these characteristics might represent an important strategy to define better therapeutic strategies.


Assuntos
Doença Enxerto-Hospedeiro , Leucemia Mielogênica Crônica BCR-ABL Positiva , Leucemia Mieloide , Aurora Quinase A/genética , Crise Blástica , Aberrações Cromossômicas , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , RNA Mensageiro , Telômero/genética
2.
BMC Public Health ; 21(1): 152, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-33461508

RESUMO

BACKGROUND: The first case of COVID-19 infection was diagnosed in Brazil 26th February 2020. By March 16th, physical distancing and confinement measures were implemented by the Brazilian government. Little is known about how these measures were followed up by the Brazilian people and their impact on daily routine. METHODS: In early April 2020, using an online platform, we organized an online survey among adults living in Brazil about their COVID-19 preventive behavior and impact on their daily routine. RESULTS: Data from 23,896 respondents were analyzed (mean age: 47.4 years). Due to COVID-19 restrictions, half (51.1%) of the professionals reported working from home. Regular handwashing was practiced by 98.7% of participants; 92.6% reported adhering to the 1.5-2 m physical distancing rule, but only 45.5% wore a face mask when going outside. While 29.3% of respondents found it relatively easy to stay at home, indoor confinement was extremely difficult for 7.9% of participants. Moreover, 11% of participants were extremely worried about their health during the COVID-19 epidemic. Younger people, male, persons living in a rural area/village or popular neighbourhoods, students and workers reported less preventive behaviour. CONCLUSION: Restrictive measures markedly affected the daily and professional routines of Brazilians. Participants showed a satisfactory level of adherence to national COVID-19 prevention guidelines. Qualitative and follow-up studies are needed to monitor the impact of COVID-19 in the Brazilian society.


Assuntos
COVID-19/epidemiologia , COVID-19/prevenção & controle , Surtos de Doenças , Fidelidade a Diretrizes/estatística & dados numéricos , Atividades Cotidianas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Feminino , Guias como Assunto , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Distanciamento Físico , Quarentena/estatística & dados numéricos , Inquéritos e Questionários , Adulto Jovem
4.
Perm J ; 242020.
Artigo em Inglês | MEDLINE | ID: mdl-32097117

RESUMO

INTRODUCTION: Delivering bad news is a difficult task for physicians, and medical schools do not always prepare future physicians for this inevitable task. OBJECTIVE: To examine training in breaking bad news, to improve medical students' competence and confidence in dealing with this important aspect of clinical practice. METHODS: An exploratory study using a qualitative approach was done at a Brazilian public university's medical school, which receives 30 medical students per semester. Two focus groups were conducted in 2018, with 15 students per group, before and after the training. The intervention consisted of a 6-month (4 h/wk) course about breaking bad news offered to 30 third-year medical students. The communication course included the perspectives of health care professionals, patients, and their families; the SPIKES protocol and the "ABCDE" mnemonic for delivering bad news; general guidelines; and role-playing/simulation strategies to improve students' skills and reduce their personal limitations. RESULTS: Results of the preintervention focus group demonstrated that only 30% of the students were aware of the importance of breaking bad news and of the existence of specific protocols to guide physicians in these situations. Findings from the postintervention focus group indicated that 90% of students understood the importance and began to apply protocols in their practice. DISCUSSION: Breaking bad news is a challenge for undergraduate medical students. The results of our qualitative study showed that students' perceptions about their capability in delivering bad news increased significantly after regular and focused training. The knowledge, skills, and attitudes acquired strengthened the students' self-reported ability to deal with situations requiring breaking bad news. CONCLUSION: The activities offered helped students develop communication skills. They made connections between their formal training (communication and cognitive skills) and actual clinical practice in a community-based rotation. The knowledge and skills acquired gave them tools needed to deliver bad news in their future clinical practice.


Assuntos
Comunicação , Processos Grupais , Aprendizagem , Estudantes de Medicina/psicologia , Revelação da Verdade , Brasil , Competência Clínica , Currículo , Emoções , Feminino , Grupos Focais , Humanos , Masculino , Relações Médico-Paciente , Pesquisa Qualitativa , Desempenho de Papéis
5.
Tumour Biol ; 37(7): 9473-81, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26790435

RESUMO

SET and MYND domain containing 2 (SMYD2) and the SET and MYND domain containing 3 (SMYD3) are the most studied and well-characterized members of SMYD family. It has been demonstrated that their altered expression is associated with the progression of several solid tumors. Nevertheless, whether these methyltransferases exert any impact in chronic lymphocytic leukemia (CLL) remains unknown. Here, we investigated the gene expression profile of SMYD2 and SMYD3 in 59 samples of CLL and 10 normal B cells. The obtained results were associated with white blood cells (WBC) and platelet counts, ZAP-70 protein expression, and cytogenetic analysis. We found that SMYD2 and SMYD3 are overexpressed in CLL patients and, interestingly, patients with residual expression of both genes presented a high WBC count and complex karyotype. Furthermore, a strong correlation between SMYD2 and SMYD3 gene expression was unveiled. Our data demonstrate the association of a residual expression of SMYD2 and SMYD3 with CLL progression indicators and suggests both genes are regulated by a common transcriptional control in this type of cancer. These results may provide the basis for the development of new therapeutic strategies to prevent CLL progression.


Assuntos
Biomarcadores Tumorais/genética , Aberrações Cromossômicas , Regulação Neoplásica da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Leucemia Linfocítica Crônica de Células B/genética , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real
6.
Blood Cells Mol Dis ; 54(1): 97-102, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25131810

RESUMO

EZH2, a histone methyltransferase, is overexpressed in several human tumors, but whether it exerts any impact in chronic lymphocytic leukemia (CLL) remains unknown. We used real time PCR to investigate the expression profile of EZH1 and EZH2 in 59 CLL patients, 10 samples of purified B-cells from healthy donors and 12 normal adult tissues. EZH2 was overexpressed in CLL patients and correlates with high white blood cell count, ZAP-70 expression and chromosomal abnormalities. EHZ1 expression does not correlate with CLL progression. EZH2 overexpression is related to a poor prognosis of CLL and could be a useful tool to assess its aggressiveness.


Assuntos
Regulação Enzimológica da Expressão Gênica , Regulação Leucêmica da Expressão Gênica , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/enzimologia , Complexo Repressor Polycomb 2/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína Potenciadora do Homólogo 2 de Zeste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Proteína-Tirosina Quinase ZAP-70/biossíntese
7.
Med Oncol ; 31(5): 931, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24683001

RESUMO

We compared the levels of AURKA and AURKB in 24 (mantle cell lymphoma) MCL patients harboring 8q abnormalities and its relationship with MYCC gene status. Two distinct subgroups were observed, in terms of MYCC expression. Except for the patients with Burkitt's-like translocation, none of the patients harboring 8q abnormalities, including balanced translocations or duplications of MYCC band, identified both by G-banding and SKY, showed differential expression levels of MYCC. These previous findings also reflected in the differential expression of AURKA and AURKB genes. We found that AURKA and AURKB mRNA were expressed at significantly higher levels in MCL patients harboring Burkitt's-like translocation, when compared to patients with 8q rearrangements. The high expression of aurora kinase genes is reported to be associated with some parameters of clinical oncologic aggressiveness, such as high histological grade, invasion and increased rates of metastasis in several types of cancers. It is possible that in MCL patients expressing abnormal levels of MYCC together with a high expression of AURKA might offer some resistant to the conventional therapy purposes. Thus, aurora kinase inhibitors may also be considered for this specific subgroup on MCL, whose aggressive clinical course resembles high-grade lymphoma.


Assuntos
Aurora Quinase A/metabolismo , Aurora Quinase B/metabolismo , Linfoma de Burkitt/genética , Cromossomos Humanos Par 8/genética , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/metabolismo , Translocação Genética/genética , Idoso , Idoso de 80 Anos ou mais , Aurora Quinase A/genética , Aurora Quinase B/genética , Western Blotting , Mapeamento Cromossômico , Feminino , Seguimentos , Humanos , Linfoma de Célula do Manto/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Proteínas Proto-Oncogênicas c-myc/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Med Oncol ; 30(1): 483, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23389918

RESUMO

We investigated the prevalence of TET2 deletion by using a new FISH probe in a cohort of 362 Brazilian patients with myeloid neoplasms and their association with cytogenetic information (G-banding analysis). Normal karyotype was observed in 45.8 % of MDS (n = 44), 43.8 % of AML (n = 39) and 46.3 % of MPN (n = 82). Abnormalities of 4q24 (deletions, translocations or inversions) were associated with another chromosomal abnormality in four patients by G-banding analysis (2 MDS, 1 AML and 1 MPN). Interphase FISH analysis revealed deletion of TET2 in 21 patients (6 patients with abnormal karyotype and in 15 patients with normal karyotype). arrayCGH analysis revealed a cryptic deletion of the region 4q24 in all eight patients selected with myeloid malignancies (3 MDS, 1 AML and 4 MPN). Considering the significantly high cost of determining the mutational status of TET2 in patient samples by using conventional sequencing methods and sometimes the lack of regular use of SNP/aCGH array methodologies, FISH for the detection of TET2 abnormalities may become a potentially useful clinical tool. The search for alterations in TET2 gene may be important for the prediction of prognosis in normal/altered AML patients' karyotype or in the disease evolution of patients with MNP and MDS.


Assuntos
Proteínas de Ligação a DNA/genética , Hibridização in Situ Fluorescente , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicas/genética , Proteínas Proto-Oncogênicas/genética , Cariótipo Anormal , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Bandeamento Cromossômico , Cromossomos Humanos Par 4 , Estudos de Coortes , Hibridização Genômica Comparativa/métodos , Dioxigenases , Feminino , Deleção de Genes , Neoplasias Hematológicas/genética , Humanos , Masculino , Pessoa de Meia-Idade
9.
Clin Cancer Res ; 18(12): 3293-304, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22539801

RESUMO

PURPOSE: Myelodysplastic syndromes (MDS) are a group of disorders characterized by cytopenias, with a propensity for evolution into acute myeloid leukemias (AML). This transformation is driven by genomic instability, but mechanisms remain unknown. Telomere dysfunction might generate genomic instability leading to cytopenias and disease progression. EXPERIMENTAL DESIGN: We undertook a pilot study of 94 patients with MDS (56 patients) and AML (38 patients). The MDS cohort consisted of refractory cytopenia with multilineage dysplasia (32 cases), refractory anemia (12 cases), refractory anemia with excess of blasts (RAEB)1 (8 cases), RAEB2 (1 case), refractory anemia with ring sideroblasts (2 cases), and MDS with isolated del(5q) (1 case). The AML cohort was composed of AML-M4 (12 cases), AML-M2 (10 cases), AML-M5 (5 cases), AML-M0 (5 cases), AML-M1 (2 cases), AML-M4eo (1 case), and AML with multidysplasia-related changes (1 case). Three-dimensional quantitative FISH of telomeres was carried out on nuclei from bone marrow samples and analyzed using TeloView. RESULTS: We defined three-dimensional nuclear telomeric profiles on the basis of telomere numbers, telomeric aggregates, telomere signal intensities, nuclear volumes, and nuclear telomere distribution. Using these parameters, we blindly subdivided the MDS patients into nine subgroups and the AML patients into six subgroups. Each of the parameters showed significant differences between MDS and AML. Combining all parameters revealed significant differences between all subgroups. Three-dimensional telomeric profiles are linked to the evolution of telomere dysfunction, defining a model of progression from MDS to AML. CONCLUSIONS: Our results show distinct three-dimensional telomeric profiles specific to patients with MDS and AML that help subgroup patients based on the severity of telomere dysfunction highlighted in the profiles.


Assuntos
Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicas/genética , Telômero/ultraestrutura , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Células da Medula Óssea/patologia , Núcleo Celular/patologia , Estudos de Coortes , Progressão da Doença , Feminino , Instabilidade Genômica , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/patologia , Projetos Piloto , Telômero/metabolismo , Adulto Jovem
10.
Med Oncol ; 29(4): 2332-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22209840

RESUMO

Chronic myelogenous leukemia (CML) is a common myeloproliferative disease that is characterized by the clonal expansion of marrow stem cells, and is associated with the Philadelphia chromosome. As the disease progresses, additional chromosome abnormalities may arise. The prognostic impact of secondary chromosomal abnormalities in CML is complex, heterogeneous, and sometimes related to previous treatment. Here, we describe a CML patient in lymphoid blast crisis associated with a new chromosomal abnormality identified, dic(7;12)(p12.21;p12.2) and i(12)(q10) using classical cytogenetics and spectral karyotype analysis. To the best of our knowledge, this is the first report of t(7;12)(p11.1;q11.1) and i(12)(q10) in a CML patient with lymphoid evolution.


Assuntos
Crise Blástica/genética , Cromossomos Humanos Par 12 , Cromossomos Humanos Par 7 , Isocromossomos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Translocação Genética , Adulto , Proteínas de Homeodomínio/genética , Humanos , Masculino , Cromossomo Filadélfia
11.
Med Oncol ; 29(2): 1227-30, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21528409

RESUMO

We report a case of a 57-year-old man diagnosed with chronic lymphocytic leukemia (CLL) and presence of a rare t(6;13)(p21;q14.1) in association with an extra copy of chromosome 12. Classical cytogenetic analysis using the immunostimulatory combination of DSP30 and IL-2 showed the karyotype 47,XY,t(6;13)(p21;q14.1), +12 in 75% of the metaphase cells. Spectral karyotype analysis (SKY) confirmed the abnormality previously seen by G-banding. Additionally, interphase fluorescence in situ hybridization using an LSI CEP 12 probe performed on peripheral blood cells without any stimulant agent showed trisomy of chromosome 12 in 67% of analyzed cells (134/200). To the best of our knowledge, the association of t(6;13)(p21;q14.1) and +12 in CLL has never been described. The prognostic significance of these new findings in CLL remains to be elucidated. However, the patient has been followed up since 2009 without any therapeutic intervention and has so far remained stable.


Assuntos
Cromossomos Humanos Par 12/genética , Cromossomos Humanos Par 13/genética , Cromossomos Humanos Par 6/genética , Leucemia Linfocítica Crônica de Células B/genética , Translocação Genética/genética , Trissomia/genética , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Pessoa de Meia-Idade
12.
Med Oncol ; 29(2): 1114-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21380778

RESUMO

Translocation (8;21)(q22;q22)/RUNX1-RUNX1T1 is a molecular marker that is usually associated with a favorable outcome in both pediatric and adult patients with acute myeloid leukemia (AML). The present report describes the results of hematologic, cytogenetic, and fluorescence in situ hybridization analysis of a case of AML with maturation in a 23-year-old woman. Cytogenetic analysis revealed a balanced translocation involving chromosomal band 21q22, which disrupts the RUNX1 gene, and 10q22, with the following karyotype: 45,X,-X,t(10;21)(q24;q22)[cp16]/46,XX [4]. Interphase FISH showed, in 67% of the 300 interphase nuclei analyzed, three signals for RUNX1 and two RUNX1T1, but no signals corresponding to RUNX1-RUNX1T1 fusion gene. These results were corroborated by RT-PCR, which revealed negative results for the amplification of RUNX1-RUNX1T1 fusion gene. The patient was refractory to conventional and salvage chemotherapy regimens and early relapsed after unrelated donor bone marrow transplantation (BMT), dying of pneumonia, acute respiratory failure, and sepsis on day +80 after BMT, 1 year after diagnosis.


Assuntos
Cromossomos Humanos Par 10/genética , Cromossomos Humanos Par 21/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Leucemia Mieloide Aguda/genética , Translocação Genética/genética , Adulto , Transplante de Medula Óssea , Evolução Fatal , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Mieloide Aguda/terapia , Doadores não Relacionados , Adulto Jovem
13.
Leuk Res ; 35(2): 260-4, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20732714

RESUMO

In the present study, we analyzed AURKA and AURKB gene expression in 70 acute myeloid leukemia (AML) patients. There was no difference between leukemic samples and bone marrow mononuclear cells (BMMCs, n = 8) or CD34(+) progenitors (n = 10) from healthy donors. High white blood cells (WBC) counts were observed in the AURKA(+) and AURKB(+) groups, but no significant differences regarding age, gender, platelet counts or frequency of FLT3-ITD mutations. AURKA, but not AURKB, expression was independently associated with high WBC counts (OR: 3.15, 95%CI 1.07-9.24, p = 0.03). Moreover, the majority of cases that overexpressed AURKA and AURKB presented unfavorable cytogenetic abnormalities (p < 0.001). In conclusion, we described a significant association between overexpression of AURKA/B and cytogenetics findings in AML, which may be relevant to new therapeutic approaches, based on Aurora kinase inhibitors.


Assuntos
Aberrações Cromossômicas , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Proteínas Serina-Treonina Quinases/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aurora Quinase A , Aurora Quinase B , Aurora Quinases , Criança , Pré-Escolar , Feminino , Perfilação da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , Leucemia Mieloide Aguda/metabolismo , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Serina-Treonina Quinases/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem , Tirosina Quinase 3 Semelhante a fms
15.
Cancer Genet Cytogenet ; 198(2): 166-9, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20362233

RESUMO

We report a case of a 47-year-old man diagnosed with chronic lymphocytic leukemia (CLL) with two extra copies of chromosome 8. Classical cytogenetic analysis by the immunostimulatory combination of DSP30 and interleukin 2 showed tetrasomy of chromosome 8 in 60% of the metaphase cells (48,XY,+8,+8[12]/46,XY[8]). Spectral karyotype analysis confirmed the abnormality previously seen by G banding. Additionally, interphase fluorescence in situ hybridization using an LSI CEP 8 probe performed on peripheral blood cells without any stimulant agent showed tetrasomy of chromosome 8 in 54% of analyzed cells (108 of 200). To our knowledge, tetrasomy 8 as the sole chromosomal abnormality in CLL has not been previously described. The prognostic significance of tetrasomy 8 in CLL remains to be elucidated. However, the patient has been followed up in the outpatient hospital since 2004 without any therapeutic intervention and has so far remained stable.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 8 , Leucemia Linfocítica Crônica de Células B/genética , Poliploidia , Análise Citogenética , Humanos , Masculino , Pessoa de Meia-Idade
16.
J Pediatr Hematol Oncol ; 31(3): 215-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19262252

RESUMO

The occurrence of pediatric cancer in children born from assisted reproductive technologies has been sporadically reported. Chromosomal characterization of the neoplasic disease in this setting is poorly described. In the present study, neuroblastoma cells from a 13-month-old infant boy born after intracytoplasmatic sperm injection were characterized by combining conventional cytogenetics, fluorescence in situ hybridization (FISH), comparative genomic hybridization, and quantitative polymerase chain reaction methods. Cytogenetic analysis of neuroblastoma (NB) metaphase spreads at the time of diagnosis revealed numerous centromere-free extrachromosomal double minutes, suggesting high MYCN amplification. Comparative genomic hybridization analysis demonstrated the amplification of 2q24 approximately pter, with additional gain of the long arm of chromosome 17. Chromosome losses involved 8q, 9q, and 11q. No deletion of 1p was found. MYCN amplification was confirmed by quantitative polymerase chain reaction and fluorescence in situ hybridization analysis. This report describes several chromosomal abnormalities that were present in NB of a child born after intracytoplasmatic sperm injection. Besides some well described and prognostic genetic findings in NB as MYCN amplification, gain on 17q and losses on 9q and 11q23, we report an unusual deletion involving 8q region in this disease. Whether this genetic abnormality may be associated to assisted reproductive technologies deserves further investigation.


Assuntos
Neoplasias Abdominais/genética , Neuroblastoma/genética , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , Injeções de Esperma Intracitoplásmicas/efeitos adversos , Neoplasias Abdominais/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Aberrações Cromossômicas , Humanos , Hibridização in Situ Fluorescente , Lactente , Recém-Nascido , Masculino , Proteína Proto-Oncogênica N-Myc , Neuroblastoma/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Neuropathology ; 29(5): 585-90, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19077038

RESUMO

Meningiomas are recognized as the most common late complication following radiotherapy. However, cytogenetic studies in childhood atypical radiation-induced meningioma are sporadic, mainly because this condition generally occurs after a long latent period. In the present study we show the results of conventional and molecular cytogenetics in a 14-year-old boy with a secondary atypical meningioma. Apart from numerical changes, we found complex aberrations with the participation of chromosomes 1, 6 and 12. The invariable presence of loss of 1p was demonstrated by fluorescent in situ hybridization (FISH) analysis with probes directed to telomeric regions and by comparative genome hybridization (CGH). Previous cytogenetic studies on adult spontaneous and radiation-associated meningiomas showed loss of chromosome 22 as the most frequent change, followed by loss of the short arm of chromosome 1. To the best of our knowledge this is the first report of highly complex chromosome aberrations in the pediatric setting of meningioma.


Assuntos
Neoplasias Encefálicas/genética , Aberrações Cromossômicas , Meningioma/genética , Neoplasias Induzidas por Radiação/genética , Segunda Neoplasia Primária/genética , Adolescente , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/radioterapia , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 12/genética , Cromossomos Humanos Par 6/genética , Terapia Combinada , Hibridização Genômica Comparativa , Humanos , Hibridização in Situ Fluorescente , Imageamento por Ressonância Magnética , Masculino , Meduloblastoma/tratamento farmacológico , Meduloblastoma/patologia , Meduloblastoma/radioterapia , Meningioma/patologia , Neoplasias Induzidas por Radiação/patologia , Segunda Neoplasia Primária/patologia
18.
Childs Nerv Syst ; 25(1): 39-45, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18946672

RESUMO

BACKGROUND: Resistance to drug is a major cause of treatment failure in pediatric brain cancer. The multidrug resistance (MDR) phenotype can be mediated by the superfamily of adenosine triphosphate-binding cassette (ABC) transporters. The dynamics of expression of the MDR genes after exposure to chemotherapy, especially the comparison between pediatric brain tumors of different histology, is poorly described. OBJECTIVE: To compare the expression profiles of the multidrug resistance genes ABCB1, ABCC1, and ABCG2 in different neuroepithelial pediatric brain tumor cell lines prior and following short-term culture with vinblastine. METHODS: Immortalized lineages from pilocytic astrocytoma (R286), anaplasic astrocytoma (UW467), glioblastoma (SF188), and medulloblastoma (UW3) were exposed to vinblastine sulphate at different schedules (10 and 60 nM for 24 and 72 h). Relative amounts of mRNA expression were analyzed by real-time quantitative polymerase chain reaction. Protein expression was assessed by immunohistochemistry for ABCB1, ABCC1, and ABCG2. RESULTS: mRNA expression of ABCB1 increased together with augmenting concentration and time of exposure to vinblastine for R286, UW467, and UW3 cell lines. Interestingly, ABCB1 levels of expression diminished in SF188. Following chemotherapy, mRNA expression of ABCC1 decreased in all cell lines other than glioblastoma. ABCG2 expression was influenced by vinblastine only for UW3. The mRNA levels showed consistent association to protein expression in the selected sets of cell lines analyzed. CONCLUSIONS: The pediatric glioblastoma cell line SF188 shows different pattern of expression of multidrug resistance genes when exposed to vinblastine. These preliminary findings may be useful in determining novel strategies of treatment for neuroepithelial pediatric brain tumors.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Resistencia a Medicamentos Antineoplásicos/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Vimblastina/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Criança , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Imuno-Histoquímica , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Leuk Res ; 33(3): 495-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18495245

RESUMO

Chronic myeloid leukemia (CML) is a rare disease in childhood which is almost exclusively associated with bcr-abl p210 (M-bcr) rearrangements. It has been suggested that co-expression of p190 and p210 may be a pathway of CML progression in adult patients. We report two cases of pediatric patients with a diagnosis of CML who presented co-expression of the p210 and p190 transcripts during progression to the blastic phase. The present data suggest that p190 may be a secondary event in at least some cases of childhood CML, suggesting an association with progression to a blastic crisis in these patients.


Assuntos
Transformação Celular Neoplásica/genética , Proteínas de Fusão bcr-abl/genética , Rearranjo Gênico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Crise Blástica , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Masculino , RNA Neoplásico/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...