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1.
Ultrasound Obstet Gynecol ; 60(3): 346-358, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35061294

RESUMO

OBJECTIVES: Early prenatal detection of congenital heart disease (CHD) allows mothers to plan for their pregnancy and delivery; however, the effect of certain sociodemographic and fetal factors on prenatal care has not been investigated thoroughly. This study evaluated the impact of maternal and fetal characteristics on the timing of prenatal diagnosis of CHD and fetal and postnatal outcomes. METHODS: This retrospective multicenter cohort study included women with a fetal echocardiographic diagnosis of CHD between 2010 and 2019. Women were grouped into quartiles of social vulnerability (quartiles 1-4; low-high) using the 2014 social vulnerability index (SVI) provided by the Centers for Disease Control and Prevention. A fetal disease severity score (range, 1-7) was calculated based on a combination of CHD severity (mild = 1; moderate = 2; severe, two ventricles = 3; severe, single ventricle = 4 points) and prenatally diagnosed genetic abnormality, non-cardiac abnormality and fetal hydrops (1 point each). Late diagnosis was defined as a fetal echocardiographic diagnosis of CHD after 24 weeks' gestation. Univariate and multivariable regression analyses were used to identify factors associated with late diagnosis, termination of pregnancy (TOP), postnatal death, prenatal-postnatal discordance in CHD diagnosis and severity and, for liveborn infants, to identify which prenatal variables were associated with postnatal death or heart transplant. RESULTS: Among 441 pregnancies included, 94 (21%) had a late diagnosis of CHD. Late diagnosis was more common in the most socially vulnerable quartile, 38% of women in this group having diagnosis > 24 weeks, compared with 14-18% in the other three quartile groups. Late diagnosis was also associated with Catholic or other Christian religion vs non-denominational or other religion and with a lower fetal disease severity score. There were 93 (21%) TOP and 26 (6%) in-utero fetal demises. Factors associated with TOP included early diagnosis and greater fetal disease severity. Compared with the other quartiles, the most socially vulnerable quartile had a higher incidence of in-utero fetal demise and a lower incidence of TOP. Among the 322 liveborn infants, 49 (15%) died or underwent heart transplant during the follow-up period (range, 0-16 months). Factors associated with postnatal death or heart transplant included longer delay between obstetric ultrasound examination at which CHD was first suspected and fetal echocardiogram at which CHD was confirmed and greater fetal disease severity. CONCLUSIONS: High social vulnerability, Catholic or other Christian religion and low fetal disease severity are associated with late prenatal CHD diagnosis. Delays in CHD diagnosis are associated with fewer TOPs and worse postnatal outcome. Therefore, efforts to expedite fetal echocardiography following abnormal obstetric screening, particularly for at-risk women (e.g. those with high SVI), have the potential to impact pregnancy and postnatal outcome among the prenatally diagnosed CHD population. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Doenças Fetais , Cardiopatias Congênitas , Estudos de Coortes , Feminino , Cardiopatias Congênitas/diagnóstico , Humanos , Lactente , Gravidez , Cuidado Pré-Natal , Diagnóstico Pré-Natal , Estudos Retrospectivos , Vulnerabilidade Social , Ultrassonografia Pré-Natal
2.
Ultrasound Obstet Gynecol ; 45(6): 657-63, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25042627

RESUMO

OBJECTIVES: To investigate the perinatal outcome of cases with a prenatal diagnosis of single-ventricle cardiac defects, single ventricle being defined as a dominant right ventricle (RV) or left ventricle (LV), in which biventricular circulation was not possible. METHODS: We reviewed patients with a prenatal diagnosis of single-ventricle cardiac defects, made at one institution between 1995 and 2008. Cases diagnosed with double-inlet LV, tricuspid atresia, pulmonary atresia with intact ventricular septum and severe RV hypoplasia and those with hypoplastic left heart syndrome (HLHS) were included in the study population. Patients with HLHS were identified prenatally as being standard risk or high risk (HLHS with highly restrictive or intact atrial septum, mitral stenosis with aortic atresia and/or LV coronary artery sinusoids). Patients with an address over 200 miles from the hospital, diagnosed with heterotaxy syndrome or referred for fetal intervention, were excluded. RESULTS: We identified 312 cases of single-ventricle cardiac defect (208 dominant RV; 104 dominant LV) that were diagnosed prenatally. Most (96%) patients with a dominant RV had HLHS. Among the total 312 cases there were 98 (31%) elective terminations of pregnancy (TOP), 12 (4%) cases of spontaneous fetal demise, 12 (4%) cases lost to prenatal follow-up and 190 (61%) live births. Among the 199 patients that underwent fetal echocardiography before 24 weeks' gestation, there were 97 (49%) cases of elective TOP. There was no difference in prenatal outcome between those with a dominant RV and those with a dominant LV (P = 0.98). Of the 190 live births, five received comfort care. With an average of 7 years' follow-up (to obtain data on the Fontan procedure), transplantation-free survival was lower in those with a dominant RV than in those with a dominant LV (standard-risk HLHS odds ratio (OR), 3.0 (P = 0.01); high-risk HLHS OR, 8.8 (P < 0.001)). CONCLUSIONS: The prenatal outcome of cases with single-ventricle cardiac defects was similar between those with a dominant RV and those with a dominant LV, however postnatal intermediate-term survival favored those with a dominant LV. High-risk HLHS identified prenatally was associated with the lowest transplantation-free survival.


Assuntos
Ventrículos do Coração/anormalidades , Síndrome do Coração Esquerdo Hipoplásico/diagnóstico por imagem , Atresia Pulmonar/diagnóstico por imagem , Atresia Tricúspide/diagnóstico por imagem , Ultrassonografia Pré-Natal , Aborto Eugênico/estatística & dados numéricos , Adolescente , Adulto , Feminino , Morte Fetal , Idade Gestacional , Transplante de Coração/mortalidade , Ventrículos do Coração/diagnóstico por imagem , Humanos , Recém-Nascido , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos , Adulto Jovem
3.
J Neurooncol ; 107(1): 133-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21984064

RESUMO

Bevacizumab is frequently used to treat patients with recurrent high-grade glioma (HGG), but responses are generally not durable. Panobinostat is a histone deacetylase inhibitor with anti-neoplastic and anti-angiogenic effects and may work synergistically with VEGF inhibitors. We performed a phase I study to evaluate the safety and tolerability of the combination of orally administered panobinostat with bevacizumab in patients with recurrent HGG. Patients with recurrent HGG were treated on a 3 + 3 trial design. Patients received bevacizumab 10 mg/kg every other week in combination with oral panobinostat. The starting dose of panobinostat was 20 mg three times per week, weekly (cohort 1). Due to concerns for thrombocytopenia with the weekly dosing regimen, the protocol was amended to examine an every other week regimen. Cohort 2 received panobinostat 20 mg three times per week, every other week, and cohort 3 received 30 mg three times per week, every other week. Dose-limiting toxicity during the first 30 days was used to determine the maximum-tolerated dose. Twelve patients (median age 50, median KPS 90) with recurrent HGG were enrolled. One dose-limiting toxicity (DLT) (Grade 3 thrombocytopenia) was observed in cohort 1. No DLTs were observed in cohorts 2 and 3. The following grade 3 toxicities were seen in one patient each: thrombocytopenia, hypophosphatemia, esophageal hemorrhage, and deep venous thrombosis. There were no grade 4 or 5 toxicities. There were three patients with partial responses and seven with stable disease. The recommended doses for further study are oral panobinostat 30 mg three times per week, every other week, in combination with bevacizumab 10 mg/kg every other week. A phase II clinical trial in recurrent HGG is underway.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Ácidos Hidroxâmicos/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica , Bevacizumab , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Feminino , Seguimentos , Glioma/mortalidade , Glioma/patologia , Humanos , Indóis , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Panobinostat , Taxa de Sobrevida , Resultado do Tratamento
4.
Proc Natl Acad Sci U S A ; 106(12): 4834-9, 2009 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-19261849

RESUMO

Although 75% of endometrial cancers are treated at an early stage, 15% to 20% of these recur. We performed an integrated analysis of genome-wide expression and copy-number data for primary endometrial carcinomas with extensive clinical and histopathological data to detect features predictive of recurrent disease. Unsupervised analysis of the expression data distinguished 2 major clusters with strikingly different phenotypes, including significant differences in disease-free survival. To identify possible mechanisms for these differences, we performed a global genomic survey of amplifications, deletions, and loss of heterozygosity, which identified 11 significantly amplified and 13 significantly deleted regions. Amplifications of 3q26.32 harboring the oncogene PIK3CA were associated with poor prognosis and segregated with the aggressive transcriptional cluster. Moreover, samples with PIK3CA amplification carried signatures associated with in vitro activation of PI3 kinase (PI3K), a signature that was shared by aggressive tumors without PIK3CA amplification. Tumors with loss of PTEN expression or PIK3CA overexpression that did not have PIK3CA amplification also shared the PI3K activation signature, high protein expression of the PI3K pathway member STMN1, and an aggressive phenotype in test and validation datasets. However, mutations of PTEN or PIK3CA were not associated with the same expression profile or aggressive phenotype. STMN1 expression had independent prognostic value. The results affirm the utility of systematic characterization of the cancer genome in clinically annotated specimens and suggest the particular importance of the PI3K pathway in patients who have aggressive endometrial cancer.


Assuntos
Neoplasias do Endométrio/enzimologia , Neoplasias do Endométrio/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genoma Humano/genética , Fosfatidilinositol 3-Quinases/metabolismo , Biomarcadores Tumorais/metabolismo , Classe I de Fosfatidilinositol 3-Quinases , Análise por Conglomerados , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/patologia , Ativação Enzimática , Feminino , Dosagem de Genes , Humanos , Perda de Heterozigosidade/genética , Prognóstico , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Estatmina/metabolismo , Análise de Sobrevida , Proteínas ras/metabolismo
5.
J Neurooncol ; 104(1): 287-91, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21153679

RESUMO

There is no effective treatment for recurrent glioblastoma (GBM) after bevacizumab failure. Putative mechanisms of resistance to bevacizumab include increased pericyte coverage, mediated partly by platelet-derived growth factor receptor (PDGFR) signaling, and an infiltrative tumor growth pattern potentially dependent on SRC. We explored the efficacy of dasatinib, a SRC, BCR-ABL, c-KIT, EPHA2, and PDGFRß inhibitor, in patients with recurrent GBM after bevacizumab failure. Adult patients with histologically confirmed GBM who failed bevacizumab therapy were treated with dasatinib 70-100 mg twice daily in combination with bevacizumab (n = 14), until tumor progression or unacceptable toxicity. Fourteen patients were treated. Median age was 55 years (range 32-66) and median KPS was 80 (range 50-90). All patients (100%) had glioblastomas. The median number of prior regimens was 4 (range from 2 to 6). Of the thirteen evaluable patients, none had a complete or partial response. Only one patient had stable disease after an 8 week interval. Median progression-free survival (PFS) was 28 days (95% confidence interval [CI] 26-35 days). Six month progression-free survival (PFS6) was 0%. Median overall survival (OS) was 78 days (95% CI 41-137 days). Treatment was moderately well-tolerated, although one patient sustained a grade 4 intracerebral hemorrhage. Dasatinib in conjunction with bevacizumab does not appear to have activity in patients with recurrent, heavily pretreated GBM.


Assuntos
Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Tiazóis/uso terapêutico , Adulto , Idoso , Bevacizumab , Neoplasias Encefálicas/fisiopatologia , Dasatinibe , Feminino , Glioblastoma/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
AJNR Am J Neuroradiol ; 41(5): 874-881, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32381545

RESUMO

BACKGROUND AND PURPOSE: Recent advances in molecular techniques have characterized distinct subtypes of diffuse intrinsic pontine gliomas. Our aim was the identification of MR imaging correlates of these subtypes. MATERIALS AND METHODS: Initial MRIs from subjects with diffuse intrinsic pontine gliomas recruited for a prospective clinical trial before treatment were analyzed. Retrospective imaging analyses included FLAIR/T2 tumor volume, tumor volume enhancing, the presence of cyst and/or necrosis, median, mean, mode, skewness, kurtosis of ADC tumor volume based on FLAIR, and enhancement at baseline. Molecular subgroups based on EGFR and MGMT mutations were established. Histone mutations were also determined (H3F3A, HIST1H3B, HIST1H3C). Univariate Cox proportional hazards regression was used to test the association of imaging predictors with overall and progression-free survival. Wilcoxon rank sum, Kruskal-Wallis, and Fisher exact tests were used to compare imaging measures among groups. RESULTS: Fifty patients had biopsy and MR imaging. The median age at trial registration was 6 years (range, 3.3-17.5 years); 52% were female. On the basis of immunohistochemical results, 48 patients were assigned to 1 of 4 subgroups: 28 in MGMT-/epidermal growth factor receptor (EGFR)-, 14 in MGMT-/EGFR+, 3 in MGMT+/EGFR-, and 3 in MGMT+/EGFR+. Twenty-three patients had histone mutations in H3F3A, 8 in HIST1H3B, and 3 in HIST1H3C. Enhancing tumor volume was near-significantly different across molecular subgroups (P = .04), after accounting for the false discovery rate. Tumor volume enhancing, median, mode, skewness, and kurtosis ADC T2-FLAIR/T2 were significantly different (P ≤ .048) between patients with H3F3A and HIST1H3B/C mutations. CONCLUSIONS: MR imaging features including enhancement and ADC histogram parameters are correlated with molecular subgroups and mutations in children with diffuse intrinsic pontine gliomas.


Assuntos
Neoplasias do Tronco Encefálico/diagnóstico por imagem , Neoplasias do Tronco Encefálico/genética , Glioma Pontino Intrínseco Difuso/diagnóstico por imagem , Glioma Pontino Intrínseco Difuso/genética , Neuroimagem/métodos , Adolescente , Criança , Pré-Escolar , Análise Mutacional de DNA/métodos , Receptores ErbB/genética , Feminino , Histonas/genética , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Mutação , Estudos Prospectivos , Estudos Retrospectivos
7.
Neuron ; 15(2): 323-31, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7544140

RESUMO

About two-thirds of the antibodies to the nicotinic acetylcholine (ACh) receptor in patients with the autoimmune disease myasthenia gravis bind to the main immunogenic region (MIR). This is small, well-defined region on each of the two alpha subunits, containing residues 67-76 (alpha 67-76). By determining the structure of the ACh receptor complexed with two different fragments of an MIR-directed antibody, we have determined the three-dimensional location of the MIR (and therefore residues alpha 67-76) to be at the extreme synaptic end of each alpha subunit. The antibody fragments extend from the binding site away from the receptor axis and into the synaptic cleft, minimizing any steric interference neighboring ACh receptors might have with their binding.


Assuntos
Reações Antígeno-Anticorpo , Autoantígenos/química , Epitopos/química , Modelos Moleculares , Conformação Proteica , Receptores Nicotínicos/química , Receptores Nicotínicos/imunologia , Animais , Especificidade de Anticorpos , Autoanticorpos/imunologia , Autoanticorpos/ultraestrutura , Autoantígenos/imunologia , Autoantígenos/ultraestrutura , Doenças Autoimunes/imunologia , Sítios de Ligação , Epitopos/imunologia , Epitopos/ultraestrutura , Humanos , Processamento de Imagem Assistida por Computador , Fragmentos Fab das Imunoglobulinas/imunologia , Microscopia Eletrônica , Miastenia Gravis/imunologia , Estrutura Terciária de Proteína , Receptores Nicotínicos/ultraestrutura , Torpedo
8.
Br J Cancer ; 98(10): 1662-9, 2008 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-18475299

RESUMO

We studied the expression of polycomb group (PcG) protein BMI-1 in a large population-based patient series of endometrial carcinomas in relation to clinical and molecular phenotype. Also, 57 fresh frozen endometrial carcinomas were studied for the relationship between BMI-1 protein expression, BMI-1 mRNA level, and activation of an 11-gene signature reported to represent a BMI-1-driven pathway. BMI-1 protein expression was significantly weaker in tumours with vascular invasion (P<0.0001), deep myometrial infiltration (P=0.004), and loss of oestrogen receptor (ER) (P<0.0001) and progesterone receptors (PR) (P=0.03). Low BMI-1 protein expression was highly associated with low BMI-1 mRNA expression (P=0.002), and similarly low BMI-1 mRNA expression correlated significantly with vascular invasion, ER and PR loss, and histologic grade 3. In contrast, activation of the reported 11-gene signature, supposed to represent a BMI-1-driven pathway, correlated with low mRNA expression of BMI-1 (P<0.001), hormone receptor loss, presence of vascular invasion, and poor prognosis. We conclude that BMI-1 protein and mRNA expression are significantly correlated and that BMI-1 expression is inversely associated with activation of the 11-gene signature. Loss of BMI-1 seems to be associated with an aggressive phenotype in endometrial carcinomas.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Proteínas Repressoras/metabolismo , Neoplasias Vasculares/metabolismo , Neoplasias Vasculares/patologia , Adulto , Idoso , Biomarcadores Tumorais/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Proteínas Nucleares/genética , Fenótipo , Complexo Repressor Polycomb 1 , Reação em Cadeia da Polimerase , Análise Serial de Proteínas , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/metabolismo , Proteínas Repressoras/genética , Análise de Sobrevida
9.
Oncogene ; 34(2): 209-16, 2015 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24362534

RESUMO

Aberrant nuclear factor (NF)-κB activation is frequently observed in human cancers. Genome characterization efforts have identified genetic alterations in multiple components of the NF-κB pathway, some of which have been shown to be essential for cancer initiation and tumor maintenance. Here, using patient tumors and cancer cell lines, we identify the NF-κB regulator, TRAF2 (tumor necrosis factor (TNF) receptor-associated factor 2), as an oncogene that is recurrently amplified and rearranged in 15% of human epithelial cancers. Suppression of TRAF2 in cancer cells harboring TRAF2 copy number gain inhibits proliferation, NF-κB activation, anchorage-independent growth and tumorigenesis. Cancer cells that are dependent on TRAF2 also require NF-κB for survival. The phosphorylation of TRAF2 at serine 11 is essential for the survival of cancer cells harboring TRAF2 amplification. Together, these observations identify TRAF2 as a frequently amplified oncogene.


Assuntos
NF-kappa B/genética , NF-kappa B/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Fator 2 Associado a Receptor de TNF/genética , Fator 2 Associado a Receptor de TNF/metabolismo , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Xenoenxertos , Humanos , Células MCF-7 , Camundongos Endogâmicos BALB C , Camundongos Nus , Oncogenes , Fosforilação , Transdução de Sinais
11.
Ultramicroscopy ; 70(1-2): 57-81, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9440347

RESUMO

Biological molecules often crystallize either as tubes, having helical symmetry, or as two-dimensional sheets. Both sorts of crystal are potentially suitable for structure determination to atomic resolution by electron crystallography, but their lattice distortions must first be corrected. We have developed a procedure for tubular crystals, based on independent alignment of very short segments against a reference structure, that allows accurate determination and correction of distortions in all three dimensions. Application of this procedure to images used previously to determine the 9 A structure of the acetylcholine receptor showed that about half of the signal loss caused by the distortions arises from effects correctable in the image plane (bending, changes in scale) and half from effects requiring out-of-plane correction (variations in tilt and in twist around the tube axis). By dividing the tubes into short segments (of lengths about equal to their diameter) it became possible to recover almost all of this loss without reducing appreciably the accuracy in the segmental alignments. The signal retention improved by only 10% at low resolution (20 A), but by progressively greater amounts at higher resolutions, up to approximately 40% at 9 A. As a result the finer structural details were more clearly resolved. With images of better electron-optical quality, much greater gains in signal retention should be obtained.


Assuntos
Receptores Colinérgicos/ultraestrutura , Animais , Artefatos , Cristalografia/métodos , Elétrons , Microscopia Eletrônica/métodos , Modelos Teóricos , Sinapses , Torpedo
12.
J Matern Fetal Neonatal Med ; 13(6): 426-8, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12962270

RESUMO

We report a case of neonatal thyrotoxicosis secondary to maternal Graves' disease. In addition to presenting with symptoms of hyperthyroidism, the infant developed conjugated hyperbilirubinemia, a finding not previously reported in children with this condition.


Assuntos
Doença de Graves/complicações , Icterícia Neonatal/diagnóstico , Troca Materno-Fetal , Complicações na Gravidez/sangue , Tireotoxicose/diagnóstico , Adulto , Feminino , Doença de Graves/sangue , Humanos , Recém-Nascido , Icterícia Neonatal/etiologia , Masculino , Gravidez , Tireotoxicose/etiologia
13.
Oncogene ; 31(29): 3397-408, 2012 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-22105362

RESUMO

Activating mutations in the RAS family or BRAF frequently occur in many types of human cancers but are rarely detected in breast tumors. However, activation of the RAS-RAF-MEK-ERK MAPK pathway is commonly observed in human breast cancers, suggesting that other genetic alterations lead to activation of this signaling pathway. To identify breast cancer oncogenes that activate the MAPK pathway, we screened a library of human kinases for their ability to induce anchorage-independent growth in a derivative of immortalized human mammary epithelial cells (HMLE). We identified p21-activated kinase 1 (PAK1) as a kinase that permitted HMLE cells to form anchorage-independent colonies. PAK1 is amplified in several human cancer types, including 30--33% of breast tumor samples and cancer cell lines. The kinase activity of PAK1 is necessary for PAK1-induced transformation. Moreover, we show that PAK1 simultaneously activates MAPK and MET signaling; the latter via inhibition of merlin. Disruption of these activities inhibits PAK1-driven anchorage-independent growth. These observations establish PAK1 amplification as an alternative mechanism for MAPK activation in human breast cancer and credential PAK1 as a breast cancer oncogene that coordinately regulates multiple signaling pathways, the cooperation of which leads to malignant transformation.


Assuntos
Neoplasias da Mama/patologia , Sistema de Sinalização das MAP Quinases/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Oncogenes , Proteínas Proto-Oncogênicas c-met/metabolismo , Quinases Ativadas por p21/genética , Quinases Ativadas por p21/metabolismo , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proliferação de Células , Transformação Celular Neoplásica/genética , Ativação Enzimática/genética , Genoma Humano/genética , Humanos , Glândulas Mamárias Humanas/citologia , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
14.
Oncogene ; 27(3): 318-22, 2008 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-17637749

RESUMO

p53-Binding protein 1 (53BP1) encodes a critical checkpoint protein that localizes to sites of DNA double-strand breaks (DSBs) and participates in DSB repair. Mice that are 53bp1 deficient or hemizygous have an increased incidence of lymphoid malignancies. However, 53BP1 abnormalities in primary human tumors have not been described. By combining high-density single nucleotide polymorphism (HD SNP) array data and gene expression profiles, we found 9 of 63 newly diagnosed human diffuse large B-cell lymphomas (DLBCLs) with single copy loss of the chromosome 15q15 region including the 53BP1 locus; these nine tumors also had significantly lower levels of 53BP1 transcripts. 53BP1 single copy loss found with the HD SNP array platform was subsequently confirmed by fluorescence in situ hybridization. These studies highlight the role of 53BP1 copy loss in primary human DLBCLs and the value of integrative analyses in detecting this genetic lesion in human tumors.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 15/genética , Dosagem de Genes , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Linfoma Difuso de Grandes Células B/genética , Alelos , Perfilação da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , Peptídeos e Proteínas de Sinalização Intracelular/genética , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Proteína 1 de Ligação à Proteína Supressora de Tumor p53
15.
Artigo em Inglês | MEDLINE | ID: mdl-16869735

RESUMO

Genome-era advances in the field of oncology endorse the notion that many tumors may prove vulnerable to targeted therapeutic avenues once their salient molecular alterations are elucidated. Accomplishing this requires both detailed genomic characterization and the ability to identify in situ the critical dependencies operant within individual tumors. To this end, DNA microarray platforms such as high-density single-nucleotide polymorphism (SNP) arrays enable large-scale cancer genome characterization, including copy number and loss-of-heterozygosity analyses at high resolution. Clustering analyses of SNP array data from a large collection of tumor samples and cell lines suggest that certain copy number alterations correlate strongly with the tissue of origin. Such lineage-restricted alterations may harbor novel cancer genes directing genesis or progression of tumors from distinct tissue types. We have explored this notion through combined analysis of genome-scale data sets from the NCI60 cancer cell line collection. Here, several melanoma cell lines clustered on the basis of increased dosage at a region of chromosome 3p containing the master melanocyte regulator MITF. Combined analysis of gene expression data and additional functional studies established MITF as an amplified oncogene in melanoma. MITF may therefore represent a nodal point within a critical lineage survival pathway operant in a subset of melanomas. These findings suggest that, like oncogene addiction, "lineage addiction" may represent a fundamental tumor survival mechanism with important therapeutic implications.


Assuntos
Genômica/métodos , Neoplasias/genética , Cromossomos Humanos Par 3/genética , Análise por Conglomerados , DNA de Neoplasias/genética , Amplificação de Genes , Dosagem de Genes , Perfilação da Expressão Gênica , Genômica/estatística & dados numéricos , Humanos , Hibridização in Situ Fluorescente , Melanoma/genética , Fator de Transcrição Associado à Microftalmia/genética , Análise de Sequência com Séries de Oligonucleotídeos , Oncogenes , Polimorfismo de Nucleotídeo Único
16.
J Neurochem ; 64(3): 1401-5, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7861173

RESUMO

We have determined the ultrastructure of 5-hydroxytryptamine3 (5-HT3) serotonin receptors purified from NG108-15 mouse neuroblastoma x rat glioma cells by electron microscopic examination of receptor particles embedded in uranyl acetate stain and metal replicas of rapidly frozen receptors. The 5-HT3 receptor can be modelled as a cylinder 11 nm in length and 8 nm in diameter with a closed end and a central cavity 3 nm in diameter. Analysis of the rotational symmetry of single receptor particles indicates that the 5-HT3 receptor is composed of five subunits arranged symmetrically around a central cavity. Together with evidence obtained for related proteins in other studies using ultrastructural, biochemical, or electrophysiological methods, our observations suggest that all members of the ligand-gated ion channel superfamily may possess a pentameric quaternary structure.


Assuntos
Receptores de Serotonina/ultraestrutura , Animais , Células Híbridas , Ativação do Canal Iônico , Camundongos , Microscopia Eletrônica , Conformação Proteica , Ratos
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