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1.
Klin Padiatr ; 227(3): 108-15, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25985445

RESUMO

Curative therapies for Ewing sarcoma have been developed within cooperative groups. Consecutive clinical trials have systematically assessed the impact and timing of local therapy and the activity of cytotoxic drugs and their combinations. They have led to an increase of long-term disease-free survival to around 70% in patients with localized disease. Translational research in ES remains an area in which interdisciplinary and international cooperation is essential for future progress. This article reviews current state-of-the art therapy, with a focus on trials performed in Europe, and summarizes novel strategies to further advance both the cure rates and quality of survival.


Assuntos
Neoplasias Ósseas/terapia , Comportamento Cooperativo , Comunicação Interdisciplinar , Sarcoma de Ewing/terapia , Neoplasias de Tecidos Moles/terapia , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Ósseas/mortalidade , Criança , Ensaios Clínicos como Assunto , Terapia Combinada , Progressão da Doença , Humanos , Terapia Neoadjuvante , Osteotomia , Radioterapia Adjuvante , Sarcoma de Ewing/mortalidade , Neoplasias de Tecidos Moles/mortalidade , Taxa de Sobrevida
2.
Sex Dev ; 5(4): 197-204, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21654156

RESUMO

We identified Bcar3 in the course of a screen for developmentally regulated genes at early developmental stages in mouse embryos. In this study, we explored the spatio-temporal expression pattern of Bcar3 during the critical time period of sex determination using in situ hybridization, real-time RT-PCR, and immunohistochemistry. We found that Bcar3 is expressed in XY gonads during early stages of gonad development and that BCAR3 localizes to Sertoli cells and germs cells. In addition, we identified a new alternative Bcar3 transcript in which exons 4-7 are deleted. This deletion could result in the generation of a truncated BCAR3 protein lacking functional domains including the SH2 domain. The data presented here suggest that Bcar3 could play a role in gonad development.


Assuntos
Expressão Gênica , Fatores de Troca do Nucleotídeo Guanina/genética , Células de Sertoli/metabolismo , Espermatozoides/metabolismo , Testículo/embriologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Éxons/genética , Feminino , Deleção de Genes , Idade Gestacional , Imuno-Histoquímica , Hibridização In Situ , Masculino , Camundongos , Ovário/química , Ovário/embriologia , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células de Sertoli/química , Processos de Determinação Sexual/genética , Espermatozoides/química , Testículo/química
3.
Gut ; 54(10): 1456-60, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15987793

RESUMO

BACKGROUND: Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene-many of which cause cystic fibrosis-have also been reported in patients with chronic pancreatitis. The authors examine whether mild or severe CFTR mutations, homozygous or compound heterozygous CFTR mutations, or even simple cystic fibrosis carrier status alone increases the risk of developing pancreatitis. METHODS: After exclusion of patients with trypsinogen (PRSS1) mutations, cystic fibrosis, or pulmonary disease, and with known risk factors for pancreatitis 67 patients with idiopathic chronic pancreatitis (ICP) from northwest Germany and 60 geographically and ethnically matched controls were recruited. The entire coding region of the CFTR gene was sequenced in all patients and controls. ICP patients were also analysed for serine protease inhibitor Kazal type 1 (SPINK1) gene mutations. RESULTS: Abnormal CFTR alleles were found to be twice as frequent in ICP patients as in controls (25/134 v 11/120; p<0.05). Three of four severe CFTR mutations detected in patients were compound heterozygous with another abnormal CFTR allele, whereas among controls three severe CFTR mutations were found in heterozygous cystic fibrosis carriers. In ICP patients 19 uncommon/mild mutations, including combinations of the 5T allele with 12TG repeats, were identified compared with only five in controls (p = 0.012). Heterozygous SPINK1 mutations were detected in eight ICP patients (15% v 1% in controls) but only one also carried an additional mild CFTR mutation. CONCLUSIONS: These data show that not only compound heterozygosity, but also cystic fibrosis carrier status for different types of CFTR mutations, including uncommon/mild mutations, significantly increase the risk of developing pancreatitis. Although 45% of the study's ICP patients carried predisposing genetic risk factors (for example, mutations in CFTR or SPINK1), the authors found no evidence that the risk conveyed by CFTR mutations depends on co-inherited SPINK1 mutations.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Pancreatite/genética , Adolescente , Adulto , Idoso , Alelos , Sequência de Bases , Proteínas de Transporte/genética , Criança , Pré-Escolar , Doença Crônica , Estudos de Coortes , Éxons/genética , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Fatores de Risco , Inibidor da Tripsina Pancreática de Kazal
4.
Neoplasma ; 51(6): 456-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15640955

RESUMO

There have been no reports on choromosomal aberrations of benign bone tumors revealed by comparative genomic hybridization (CGH). CGH analysis of benign tumors may be useful in understanding the mechanism of tumorigenesis with comparisons to malignant tumors. There were 4 tumors (2 enchondromas, one chondromyxoid fibroma, and one osteoid osteoma) and 8 tumor-like conditions (4 aneurysmal bone cysts (ABCs), one eosinophilic granuloma, one fibrous dysplasia, one solitary bone cyst, and one Rosai-Dorfman disease) available for analysis. One of 2 enchondromas and one of 4 ABCs exhibited rapid growth. Six lesions showed chromosomal aberrations, while 6 others did not. The most frequent aberrations were the loss of a whole chromosome-19 in 6 cases, the loss of chromosome-arm 22q in 4 cases, and the loss of chromosome-arm 17p in 3 cases. Gains were seen in 13q21 in 2 cartilaginous tumors and at 12q15-q21 in eosinophilic granulomas. Therefore, in benign bone tumors or tumor-like lesions, chromosomal aberrations are not frequent; however, some clear tendencies of clustering of aberrations can be observed.


Assuntos
Neoplasias Ósseas/genética , Aberrações Cromossômicas , Adolescente , Adulto , Criança , Deleção Cromossômica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico
5.
Ann Oncol ; 13(10): 1656-64, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12377657

RESUMO

BACKGROUND: The incidence of Ewing's tumors (ETs) is lower in Asians or African-Americans than in Caucasians. PATIENTS AND METHODS: Japanese ETs were available for analysis of chromosomal aberrations by comparative genomic hybridization (n = 16) and for expression of chimeric EWS transcripts by reverse-transcriptase polymerase chain reaction (n = 11). These results in Japanese patients were compared with those of 62 ETs in European Caucasian patients registered in the European Intergroup Cooperative Ewing's Sarcoma Study. RESULTS: Japanese patients with ET had lower overall survival (P = 0.0446) and relapse-free survival (P = 0.0371) compared with European Caucasian patients. Ten of 11 Japanese ETs and 31 of 62 European Caucasian ETs had type I (EWS exon 7 to FLI1 exon 6) fusion transcripts. In Japanese ETs, the median numbers of chromosomal aberrations were 2.0 and 6.0 in 11 primary tumors and five relapsed tumors, respectively. In European Caucasian ETs, the median number of changes were 2.5 and 5.0 in 52 primary and 10 relapsed tumors, respectively. Frequent gains were 8q (38%), 8p (31%) and 12q (25%) in Japanese ETs and 8q (52%), 8p (48%) and 12q (19%) in European Caucasian ETs. Frequent losses were 19q (44%), 19p (38%) and 17p (25%) in Japanese ETs and 16q (21%), 19q (18%) and 17p (15%) in European Caucasian ETs. The incidence of losses of 19p (P = 0.0215) and 19q (P = 0.0277) were significantly higher in Japanese ETs than in European Caucasian ETs. An amplification (1p33-p34) was observed in only one Japanese ET. CONCLUSIONS: Japanese patients with ET in this study had a worse prognosis than European Caucasian patients. In molecular genetic analyses, Japanese ETs had a higher frequency of loss of chromosome 19 than European Caucasian ETs. Different genetic aberrations may explain the different incidences and prognoses of ET between Caucasian and Japanese patients.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 19 , DNA de Neoplasias/genética , Sarcoma de Ewing/etnologia , Sarcoma de Ewing/genética , População Branca , Adolescente , Adulto , Criança , Europa (Continente)/etnologia , Feminino , Genes erbB-2 , Humanos , Incidência , Japão/etnologia , Masculino , Hibridização de Ácido Nucleico , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoma de Ewing/patologia , Sobrevida
7.
Int J Pediatr Otorhinolaryngol ; 63(1): 61-5, 2002 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11879931

RESUMO

Synovial sarcomas of the head and neck are rare. Typically, they are localized laterally in the parapharyngeal space. We report the case of an 8-year-old girl with a monophasic round cell synovial sarcoma of the anterior neck, clinically resembling a thyroglossal duct cyst. Histologic, immunohistochemic and cytogenetic findings are presented with a brief review of the literature. This case reaffirms the importance of considering malignant neoplasms in the differential diagnosis of pediatric neck masses.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Sarcoma Sinovial/diagnóstico , Criança , Diagnóstico Diferencial , Feminino , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Sarcoma Sinovial/cirurgia , Cisto Tireoglosso/diagnóstico
8.
Nephrol Dial Transplant ; 16(12): 2323-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11733623

RESUMO

BACKGROUND: Previous studies concerning Alu I/D polymorphism in the ACE gene and ADPKD severity have used the Alu genotypes as a representative of the true biological variable, namely ACE activity. However, wide individual and ethnic differences in the proportion of variance in ACE activity explained by the I/D genotype may have confounded these studies. This investigation examines the association between ADPKD severity and ACE in terms of plasma enzyme activity and I/D genotypes in individuals from three different countries. METHODS: Blood samples were collected from 307 ADPKD patients (116 Australian, 124 Bulgarian and 67 Polish) for determination of ACE activity levels and I/D genotypes. Chronic renal failure (CRF) was present in 117 patients and end-stage renal failure (ESRF) in 68 patients. RESULTS: ACE activity was related to the I/D genotype, showing a dosage effect of the D allele (P=0.006). The proportion of variance due to the Alu polymorphism was 14%. No difference in ACE activity and I/D genotype distribution was found between patients with CRF versus normal renal function (P=0.494; P=0.576) or between those with ESRF versus those without ESRF (P=0.872; P=0.825). No effect of the I/D genotype on age at development and progression to renal failure (CRF; ESRF) was detected in the overall group, and in subgroups based on ethnic origin, linkage status and sex. CONCLUSION: ACE is not likely to play a role as a determinant of ADPKD phenotype severity.


Assuntos
Peptidil Dipeptidase A/sangue , Peptidil Dipeptidase A/genética , Rim Policístico Autossômico Dominante/enzimologia , Rim Policístico Autossômico Dominante/genética , Polimorfismo Genético , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Criança , Elementos de DNA Transponíveis , Feminino , Deleção de Genes , Humanos , Hipertensão/complicações , Rim/fisiopatologia , Falência Renal Crônica/etiologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Rim Policístico Autossômico Dominante/complicações , Rim Policístico Autossômico Dominante/fisiopatologia , Índice de Gravidade de Doença
9.
Eur J Clin Invest ; 31(10): 907-14, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11737230

RESUMO

OBJECTIVES: EPB4.1 has been previously mapped to human chromosome 1p33-p34.2. In contradiction to this chromosomal location, we have mapped EPB4.1-1p36 by using fluorescence in situ hybridization and radiation hybrid mapping. In neuroblastomas, deletions of the telomeric end of chromosome 1 (1p36) are the most common genetic aberration. METHODS: We investigated whether genetic aberrations of EPB4.1 can be detected in some neuroblastomas by analyzing 72 tumours for EPB4.1 mutation, expression, and alternative splicing pattern. Furthermore, EPB4.1 protein from a neuroblastoma cell line was studied for its subcellular localization. RESULTS: Sequence changes could be detected in 14 out of 72 neuroblastomas, including missense, silent, and intronic changes. Duplex RT-PCR analysis revealed a subset of 11 tumours expressing significantly low levels of EPB4.1. Significant EPB4.1 sequence changes that were detected included an exon 4 G/A missense mutation (amino acid: V/I) that was shown to be associated with absence of wild-type EPB4.1 expression (3 tumours), an exon 8 G/A missense mutation (V/M) (1 tumour), and an intronic sequence change that was shown to be associated with the presence of an aberrant transcript (1 tumour). Splicing pattern analysis revealed that all EPB4.1 transcripts from tumours exclude exon 3, a splicing pattern for generating the 135 kDa isoform. EPB4.1 cDNA cloned from a neuroblastoma cell line produced a 135-kDa protein with a cytoplasm/membrane localization. CONCLUSIONS: Out of 72 neuroblastomas we have identified 11 tumours with impaired EPB4.1 expression and 5 tumours with significant sequence changes. We also found that the 135 kDa isoform is the main EPB4.1 product in neuroblastoma. EPB4.1 cDNA from a neuroblastoma cell line produced a 135-kDa protein and displayed a cytoplasm/membrane localization in transfected cells.


Assuntos
Cromossomos Humanos Par 1/genética , Proteínas do Citoesqueleto , Proteínas de Membrana/genética , Neuroblastoma/genética , Neuropeptídeos , Processamento Alternativo , Sequência de Bases , Deleção Cromossômica , Mapeamento Cromossômico , Análise Mutacional de DNA , DNA Complementar/genética , DNA de Neoplasias/genética , Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , Proteínas de Membrana/metabolismo , Membranas/metabolismo , Mutação , Neuroblastoma/metabolismo , Isoformas de Proteínas/genética , Células Tumorais Cultivadas
10.
Hum Mutat ; 18(6): 546, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11748850

RESUMO

Haemophilia A is a X-linked bleeding disorder, caused by deficiency in the activity of coagulation factor VIII due to mutations in the corresponding gene. The most common defect in patients is an inversion of the factor VIII gene that accounts for nearly 45% of individuals with severe hemophilia A. Point mutations and small deletions/insertions are responsible for the majority of cases with moderate to mild clinical course and for half of the severe hemophilia A occurrences. The majority of these mutations are "private", because of the high mutation rate for this particular gene. We report on eleven pathological changes in the factor VIII sequence detected in male patients with haemophilia A or in female obligate carriers. Seven of these mutations are novel [E204N, E265X, M320T, F436C, S535C, N2129M and R2307P] and four have been previously identified [V162M, R527W, R1966X, and R2159C]. Genotype-phenotype correlations and computer prediction analysis on the effect of missense mutations on the secondary structure of the factor VIII protein are performed and the relationships evaluated.


Assuntos
Fator VIII/genética , Hemofilia A/genética , DNA/química , DNA/genética , Análise Mutacional de DNA , Feminino , Genótipo , Hemofilia A/patologia , Heterozigoto , Humanos , Masculino , Mutação de Sentido Incorreto , Fenótipo , Mutação Puntual
11.
Oncogene ; 20(41): 5865-77, 2001 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-11593392

RESUMO

Resistance of tumors to treatment with cytotoxic drugs, irradiation or immunotherapy may be due to disrupted apoptosis programs. Here, we report in a variety of different tumor cells including Ewing tumor, neuroblastoma, malignant brain tumors and melanoma that caspase-8 expression acts as a key determinant of sensitivity for apoptosis induced by death-inducing ligands or cytotoxic drugs. In tumor cell lines resistant to TRAIL, anti-CD95 or TNFalpha, caspase-8 protein and mRNA expression was decreased or absent without caspase-8 gene loss. Methylation-specific PCR revealed hypermethylation of caspase-8 regulatory sequences in cells with impaired caspase-8 expression. Treatment with the demethylation agent 5-Aza-2'-deoxycytidine (5-dAzaC) reversed hypermethylation of caspase-8 resulting in restoration of caspase-8 expression and recruitment and activation of caspase-8 at the CD95 DISC upon receptor cross-linking thereby sensitizing for death receptor-, and importantly, also for drug-induced apoptosis. Inhibition of caspase-8 activity also inhibited apoptosis sensitization by 5-dAzaC. Similar to demethylation, introduction of caspase-8 by gene transfer sensitized for apoptosis induction. Hypermethylation of caspase-8 was linked to reduced caspase-8 expression in different tumor cell lines in vitro and, most importantly, also in primary tumor samples. Thus, these findings indicate that re-expression of caspase-8, e.g. by demethylation or caspase-8 gene transfer, might be an effective strategy to restore sensitivity for chemotherapy- or death receptor-induced apoptosis in various tumors in vivo.


Assuntos
Neoplasias Ósseas/metabolismo , Caspases/metabolismo , Resistencia a Medicamentos Antineoplásicos/fisiologia , Glicoproteínas de Membrana/farmacologia , Proteínas de Neoplasias/metabolismo , Sarcoma de Ewing/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Apoptose , Proteínas Reguladoras de Apoptose , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Neoplasias Ósseas/tratamento farmacológico , Caspase 3 , Caspase 8 , Caspase 9 , Caspases/genética , Metilases de Modificação do DNA/farmacologia , Decitabina , Regulação para Baixo , Indução Enzimática/efeitos dos fármacos , Técnicas de Transferência de Genes , Humanos , Metilação , Proteínas de Neoplasias/genética , RNA Mensageiro/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Sarcoma de Ewing/tratamento farmacológico , Ligante Indutor de Apoptose Relacionado a TNF , Células Tumorais Cultivadas
12.
Genes Chromosomes Cancer ; 32(2): 164-71, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11550284

RESUMO

Ewing tumors are characterized by reciprocal translocations involving the EWS gene on 22q12 fused to ETS transcription-factor family members. Little is known about further aberrations contributing to tumor development and progression. Sixty-two frozen tumors with known EWS rearrangements (52 primary tumors, 10 relapses) of ET patients registered in the EICESS protocol were analyzed by comparative genomic hybridization (CGH). The median number of changes in 52 primary and 10 relapsed cases was 2.5 and 5.0 per tumor (P = 0.153). Frequent abnormalities included gains of chromosomes 8, 12, 20, and 1q and losses of 16q and 19q. Neither number nor type of aberration was associated with histology, tumor size, disease stage, tumor localization, or histologic tumor response to chemotherapy. Among the 52 primary tumors, 26 with Type I fusion (EWS exon 7 to FLI1 exon 6) and 26 with other fusion types had a median of 2.0 and 3.0 aberrations per tumor, respectively (P = 0.031). Combinations of gains of chromosomes 8 and 12, gains of chromosome 20, and either gains of 8q or 18q and losses of 16q and 17p frequently occurred. The cumulative overall survival (OAS) was different between 35 patients with <5 aberrations and 13 patients with > or =5 aberrations (P = 0.009). Univariate analysis showed that patients with gains of 1q, 2q, 12, and 20 or losses of 16q and 17p had significantly lower OAS than those without aberrations. By multivariate analysis, loss of 16q (relative risk [RR] = 5.3; P = 0.0006) was an independent prognostic factor.


Assuntos
Neoplasias Ósseas/genética , Deleção Cromossômica , Hibridização de Ácido Nucleico/métodos , Sarcoma de Ewing/genética , Adolescente , Adulto , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/patologia , Criança , Pré-Escolar , Aberrações Cromossômicas/genética , Transtornos Cromossômicos , Feminino , Seguimentos , Amplificação de Genes/genética , Humanos , Masculino , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/patologia , Sarcoma de Ewing/secundário , Fatores Sexuais , Translocação Genética/genética
13.
Klin Padiatr ; 213(4): 186-90, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11528552

RESUMO

BACKGROUND: Neuroblastomas (NB) are a heterogeneous group of childhood tumours with a wide range of likelihood for tumour progression. As traditional parameters do not ensure completely accurate prognostic grouping, new molecular markers are needed for assessing the individual patient's prognosis more precisely. PATIENTS AND METHODS: 133 NB of all stages were analysed in blind-trial fashion for telomerase activity (TA), expression of surviving, and MYCN status. These data were correlated with other traditional prognostic indicators and disease outcome. RESULTS AND CONCLUSIONS: TA is a powerful independent prognostic marker for all stages and is capable of differentiating between good and poor outcome in putative "favourable" clinical or biological subgroups of NB patients. High surviving expression is associated with an adverse outcome, but is more difficult to interprete than TA because survivin expression needs to be accurately quantified to be of predictive value. We propose an extended progression model for NB including emerging prognostic markers, with emphasis on telomerase activity.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/diagnóstico , Proteínas Cromossômicas não Histona/genética , Genes myc/genética , Proteínas Associadas aos Microtúbulos , Neuroblastoma/diagnóstico , Telomerase/genética , Southern Blotting , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Pré-Escolar , Progressão da Doença , Feminino , Imunoensaio de Fluorescência por Polarização , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas In Vitro , Lactente , Proteínas Inibidoras de Apoptose , Masculino , Modelos Biológicos , Proteínas de Neoplasias , Neuroblastoma/genética , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Neuroblastoma/terapia , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Método Simples-Cego , Análise de Sobrevida , Survivina , Resultado do Tratamento
14.
Oncogene ; 20(29): 3835-44, 2001 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-11439347

RESUMO

Telomere maintenance is regarded as a key mechanism in overcoming cellular senescence in tumor cells and in most cases is achieved by the activation of telomerase. However there is at least one alternative mechanism of telomere lengthening (ALT) which is characterized by heterogeneous and elongated telomeres in the absence of telomerase activity (TA). We evaluated the prevalence of TA, gene expression of telomerase subunits and ALT in relation to telomere morphology and function in matrix producing bone tumors and in osteosarcoma cell lines and present evidence of a direct association of ALT with telomere dysfunction and chromosomal instability. Telomere fluorescence in situ hybridization (T-FISH) in ALT cells revealed elongated and shortened telomeres, partly in unusual configurations and loci, dicentric marker chromosomes and signal-free chromosome ends. Free ends give rise to end-to-end associations and may induce breakage-fusion-bridge cycles resulting in an increased number of complex chromosomal rearrangements, as detected by multiplex-FISH (M-FISH). We propose that ALT cannot be seen as an equivalent to telomerase activity in telomere maintenance. Its association with telomere dysfunction and chromosomal instability may have major implications for tumor progression.


Assuntos
Neoplasias Ósseas/genética , Osteossarcoma/genética , Telômero , Adulto , Neoplasias Ósseas/patologia , Humanos , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Osteossarcoma/patologia , Telomerase/metabolismo , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
15.
Med Pediatr Oncol ; 36(1): 11-3, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11464859

RESUMO

PROCEDURE: To establish the significance of chromosome 17 aberrations in the biology of neuroblastomas, the fresh-frozen material of 53 primary neuroblastomas (average patient age: 20.8 months; stage 1 or 2: n = 10; stage 3: n = 10; stage 4: n = 10; stage 4s: n = 23) was studied by means of comparative genomic hybridization (CGH). Follow-up data were available for 52 of 53 cases studied (average follow-up period: 26.4 months). Except for one, all cases had previously been analyzed for MYCN status (semiquantitative Southern blot analysis). Studies of LOH 1p36 (VNTR-PCR) had been performed on 28 of 53 cases. RESULTS: Chromosome 17 gains were detected in 46 of 53 (86.8%) cases. Whole chromosome gains were mostly restricted to localized tumors (stage 1 or 2: 9 of 10 cases; stage 4s:19 of 23; stage 3: 2 of 10; stage 4:0 of 10 cases), whereas distal 17 gains were significantly associated with clinically advanced tumor stages and patients aged over 1 year at diagnosis. Univariate analyses revealed a statistically significant correlation of distal 17q gains with overall survival (P< 0.01, MYCN amplification: P< 0.01; 1p deletion: P< 0.01) and an elevated recurrency rate (17q: P= 0.02, MYCN amplification: P = 0.05; 1p deletion P= 0.3). There was a strong coincidence of distal 17q gains and 1p deletion or MYCN amplification (P < 0.01). CONCLUSION: Our data indicate that distal chromosome 17q gains are of major prognostic relevance for neuroblastoma patients. However, studies on a larger series of tumors have to be performed to assess whether or not these alterations are independent prognostic markers of a poor clinical outcome.


Assuntos
Cromossomos Humanos Par 17/ultraestrutura , Neuroblastoma/genética , Hibridização de Ácido Nucleico , Criança , Pré-Escolar , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 1/ultraestrutura , Cromossomos Humanos Par 17/genética , Seguimentos , Amplificação de Genes , Genes myc , Humanos , Lactente , Tábuas de Vida , Estadiamento de Neoplasias , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Prognóstico , Análise de Sobrevida , Trissomia
16.
Appl Immunohistochem Mol Morphol ; 9(2): 143-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11396632

RESUMO

Sporadic adenomas are said to exhibit an orderly growth pattern with a reversal of proliferative and apoptotic cell distribution as compared with normal colonic crypts. Dysplastic polyps of patients with ulcerative colitis (UC) may represent dysplasia-associated lesions or masses (DALM) with a high associated cancer risk, or, alternatively, may represent sporadic adenomas. Histologic criteria to differentiate between sporadic adenomas and DALM have not focused on the balance between cell renewal and cell loss. The expression of the novel anti-apoptosis gene product, survivin, and the proliferation markers, Ki-67 and Y-box binding protein (YB-1), were investigated by immunohistochemical localization in sporadic adenomas and DALM lesions of patients with UC. In adenomas, KI-67 was expressed preponderantly at the luminal aspect of the polyp, whereas its expression was diffuse in DALM. Survivin was detected diffusely in both adenomas and DALM. YB-1 showed positive staining in the deep aspect of adenomatous glands but only to a minor degree at the surface, whereas both deep and diffuse expression patterns of YB-1 were seen in DALM. The authors conclude that DALM and sporadic adenomas exhibit different patterns of cellular proliferation and that molecular markers of cell proliferation, Ki-67 and YB-1, may be useful to distinguish sporadic adenomas from DALM. However, the similar expression of survivin suggests that the underlying mechanisms that regulate apoptotic cell death are uniform in these lesions.


Assuntos
Adenoma/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Colite Ulcerativa/metabolismo , Proteínas de Ligação a DNA , Antígeno Ki-67/metabolismo , Proteínas Associadas aos Microtúbulos , Fatores de Transcrição , Adenoma/patologia , Animais , Sequência de Bases , Proteínas Cromossômicas não Histona/genética , Colite Ulcerativa/patologia , Colo/metabolismo , Colo/patologia , Inibidores de Cisteína Proteinase/metabolismo , Feminino , Humanos , Immunoblotting , Imuno-Histoquímica , Proteínas Inibidoras de Apoptose , Masculino , Dados de Sequência Molecular , Fatores de Transcrição NFI , Proteínas de Neoplasias , Proteínas Nucleares , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Survivina , Proteína 1 de Ligação a Y-Box
17.
J Pathol ; 194(2): 165-70, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11400144

RESUMO

Ductal invasive grade (G) 2 and G3 carcinomas represent the majority of invasive breast cancers. Previous morphological and cytogenetic studies have provided evidence that ductal invasive G2 carcinoma may originate from at least two different genetic pathways. The aim of this study was to evaluate further the heterogeneity of G2 breast cancer in comparison with G3 cancers by cytogenetic and quantitative analysis. To this end, 35 cases of ductal invasive G2 and 42 cases of ductal invasive G3 carcinomas were investigated by means of comparative genomic hybridization (CGH) and these findings were correlated with DNA ploidy status, mitotic activity index (MAI), mean nuclear area (MNA), volume per lumen (VPL), and clinico-pathological parameters. The findings of this study demonstrate that ductal invasive G2 carcinomas, in contrast to ductal invasive G3 carcinomas, have to be interpreted as the morphological end stage resulting from two different cytogenetic and morphological pathways; the loss of 16q material is the cytogenetic key event in the evolution of a subgroup of this entity. By correlating genetic alterations with DNA ploidy status, an extended morphology-based cytogenetic progression model is presented, with early and late genetic alterations in the pathogenesis of breast cancer. The correlation with MAI gives rise to the hypothesis that these different genetic pathways significantly differ in their proliferation rate. Further studies will be required to elucidate which genes contribute to an altered proliferation rate in these subgroups and to the associated prognosis.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patologia , Aberrações Cromossômicas/genética , Aberrações Cromossômicas/patologia , Modelos Genéticos , Transtornos Cromossômicos , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 13 , Cromossomos Humanos Par 16 , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 20 , Cromossomos Humanos Par 8 , Progressão da Doença , Feminino , Amplificação de Genes , Deleção de Genes , Marcadores Genéticos , Humanos , Índice Mitótico , Hibridização de Ácido Nucleico/métodos , Ploidias , Estatísticas não Paramétricas
18.
Genomics ; 74(3): 333-41, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11414761

RESUMO

PKD1 is the first gene identified to be causative for the condition of autosomal dominant polycystic kidney disease. There are several genes homologous to PKD1 that are located proximal to the master gene on the same chromosome. Two of these genes have been recently covered in a large sequencing work on chromosome 16, and their structure has been broadly analyzed. However, the major question whether homologous genes (HG) code for functionally active polypeptides has not been resolved so far. The current study identifies and partially characterizes four more homologues of PKD1, different from the previously published sequence, two of which were found by screening of a BAC library and the other two contained in available databases. Analysis of HG transcripts shows that they are not translated in the model cell line T98G. Taken together, these findings suggest that homologues to PKD1 form a family of pseudogenes.


Assuntos
Rim Policístico Autossômico Dominante/genética , Proteínas/genética , Pseudogenes/genética , Sequência de Bases , DNA/química , DNA/genética , Humanos , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Canais de Cátion TRPP , Transcrição Gênica , Células Tumorais Cultivadas
19.
Am J Pathol ; 158(4): 1525-32, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11290570

RESUMO

We studied 23 pediatric high-grade astrocytomas by comparative genomic hybridization. Chromosomal imbalances were found in 10 of 10 anaplastic astrocytomas and 11 of 13 glioblastomas and consisted of +1q (43%), +3q (26%), +1p, +2q, +5q (22%), -22q (34%), -6q, -10q (30%), -9q, -11q, -13q, -16q, and -17p (22%). Anaplastic astrocytomas frequently showed +5q (40%), +1q (30%), -22q (50%), -6q, -9q (40%), and -12q (30%); glioblastomas +1q (54%), +3q (38%), +2q, +17q (23%), -6q, -8q, -10q, -13q, and -17p (31%). Minimal common regions mapped to +1q21-41, +3q27-qter, +2q31-32, +5q14-22, -22q12-qter, -10q23-25, -6q25-qter, -9q34.2, -11q14-22, -16q22-qter, and -17p. High-level gains were located on 1q (7 cases), 2q, 7q (4 cases), 3q (3 cases), 9, 17q (2 cases), 4q, 8q, 18, and 20q (1 case). A significantly shorter survival was found for anaplastic astrocytomas showing +1q (P: < 0.05), MIB-1 proliferation index >25% (P: < 0.001) and glioblastomas (P: < 0.05). Compared with adult cases, +1p, +2q, and +21q as well as -6q, -11q, and -16q were more frequent in pediatric malignant astrocytomas. Among the latter +5q, -6q, -9q, -12q, and -22q were characteristic for pediatric anaplastic astrocytomas and +1q, +3q, +16p, -8q, and -17p for pediatric glioblastomas. Our results show that chromosomal aberrations differ between pediatric anaplastic astrocytomas and glioblastomas as well as between pediatric and adult high-grade astrocytomas, supporting the notion of a different genetic pathway. Furthermore, gains of chromosomal material on 1q might be correlated with a worse prognosis in pediatric anaplastic astrocytomas.


Assuntos
Astrocitoma/genética , Neoplasias Encefálicas/genética , Aberrações Cromossômicas , Adolescente , Astrocitoma/metabolismo , Astrocitoma/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Divisão Celular , Criança , Pré-Escolar , Feminino , Dosagem de Genes , Glioblastoma/genética , Humanos , Lactente , Antígeno Ki-67/metabolismo , Masculino , Hibridização de Ácido Nucleico , Análise de Sobrevida
20.
J Clin Oncol ; 19(6): 1818-29, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11251014

RESUMO

PURPOSE: Cooperative Ewing's Sarcoma Study (CESS) 86 aimed at improving event-free survival (EFS) in patients with high-risk localized Ewing tumor of bone. PATIENTS AND METHODS: We analyzed 301 patients recruited from January 1986 to July 1991 (60% male; median age 15 years). Tumors of volume >100 mL and/or at central-axis sites qualified patients for "high risk" (HR, n = 241), and small extremity lesions for "standard risk" (SR, n = 52). Standard-risk patients received 12 courses of vincristine, cyclophosphamide, and doxorubicin alternating with actinomycin D (VACA); HR patients received ifosfamide instead of cyclophosphamide (VAIA). Tumor sites were pelvis (27%), other central axis (28%), femur (19%), or other extremity (26%). The initial tumor volume was <100 mL in 33% of cases and > or =100 mL in 67%. Local therapy was surgery (23%), surgery plus radiotherapy (49%), or radiotherapy alone (28%). Event-free survival rates were estimated by Kaplan-Meier analyses, comparisons were done by log-rank test, and risk factors were analyzed by Cox models. RESULTS: On May 1, 1999 (median time under study, 133 months), the 10-year EFS was 0.52. Event-free survival did not differ between SR-VACA (0.52) and HR-VAIA (0.51, P =.92). Tumor volume of >200 mL (EFS, 0.36 v 0.63 for smaller tumors; P =.0001) and poor histologic response (EFS, 0.38 v 0.64 for good responders; P =.0007) had negative impacts on EFS. In multivariate analyses, small tumor volumes of <200 mL, good histologic response, and VAIA chemotherapy augured for fair outcome. Six of 301 patients (2%) died under treatment, and four patients (1.3%) developed second malignancies. CONCLUSION: Fifty-two percent of CESS 86 patients survived after risk-adapted therapy. High-risk patients seem to have benefited from intensified treatment that incorporated ifosfamide.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Sarcoma de Ewing/tratamento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/cirurgia , Quimioterapia Adjuvante , Criança , Pré-Escolar , Ciclofosfamida/administração & dosagem , Dactinomicina/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Humanos , Ifosfamida/administração & dosagem , Lactente , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Radioterapia Adjuvante , Fatores de Risco , Sarcoma de Ewing/radioterapia , Sarcoma de Ewing/cirurgia , Análise de Sobrevida , Resultado do Tratamento , Vincristina/administração & dosagem
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