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1.
J Eur Acad Dermatol Venereol ; 34(10): 2353-2361, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32078194

RESUMO

BACKGROUND: Mutations in the γ-secretase enzyme subunits have been described in multiple kindreds with familial hidradenitis suppurativa (HS). OBJECTIVE: In this study, we report a novel nicastrin (NCSTN) mutation causing HS in a Dutch family. We sought to explore the immunobiological function of NCSTN mutations using data of the Immunological Genome Project. METHODS: Blood samples of three affected and two unaffected family members were collected. Whole-genome sequencing was performed using genomic DNA isolated from peripheral blood leucocytes. Sanger sequencing was done to confirm the causative NCSTN variant and the familial segregation. The microarray data set of the Immunological Genome Project was used for thorough dissection of the expression and function of wildtype NCSTN in the immune system. RESULTS: In a family consisting of 23 members, we found an autosomal dominant inheritance pattern of HS and detected a novel splice site mutation (c.1912_1915delCAGT) in the NCSTN gene resulting in a frameshift and subsequent premature stop. All affected individuals had HS lesions on non-flexural and atypical locations. Wildtype NCSTN appears to be upregulated in myeloid cells like monocytes and macrophages, and in mesenchymal cells such as fibroblastic reticular cells and fibroblasts. In addition, within the 25 highest co-expressed genes with NCSTN we identified CAPNS1, ARNT and PPARD. CONCLUSION: This study reports the identification a novel NCSTN gene splice site mutation which causes familial HS. The associated immunobiological functions of NCSTN and its co-expressed genes ARNT and PPARD link genetics to the most common environmental and metabolic HS risk factors which are smoking and obesity.


Assuntos
Hidradenite Supurativa , Secretases da Proteína Precursora do Amiloide/genética , Calpaína , Hidradenite Supurativa/genética , Humanos , Glicoproteínas de Membrana , Mutação , Fatores de Transcrição
2.
Eur J Clin Microbiol Infect Dis ; 36(3): 495-499, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27889877

RESUMO

The use of MALDI-TOF MS (matrix-assisted laser desorption/ ionization-time of flight mass spectrometry) and WGS (whole genome sequencing) has been described for identification and strain relatedness determination. We describe the complementary use of MALDI-TOF MS and WGS in a VRE (vancomycin-resistant enterococci) outbreak investigation, and discuss some of the challenges with defining strain similarity across these two platforms. Although both assays indicated multiple clusters involved in the outbreak of vancomycin resistant Enterococcus faecium isolates from positive blood cultures of four haematology-oncology patients, the small cohort and discrepancies between findings indicate the limitations of MALDI-TOF MS and the cautious interpretation of MALDI-TOF MS dendrograms during outbreaks. For definitive determination of the evolutionary distance between isolates, WGS can be used.


Assuntos
Surtos de Doenças , Enterococcus faecium/classificação , Infecções por Bactérias Gram-Positivas/epidemiologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Enterococos Resistentes à Vancomicina/classificação , Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Técnicas de Tipagem Bacteriana/métodos , Enterococcus faecium/química , Enterococcus faecium/genética , Enterococcus faecium/isolamento & purificação , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Epidemiologia Molecular/métodos , Enterococos Resistentes à Vancomicina/química , Enterococos Resistentes à Vancomicina/genética , Enterococos Resistentes à Vancomicina/isolamento & purificação
3.
Mol Ecol ; 25(2): 598-615, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-26614983

RESUMO

Venoms comprise of complex mixtures of peptides evolved for predation and defensive purposes. Remarkably, some carnivorous cone snails can inject two distinct venoms in response to predatory or defensive stimuli, providing a unique opportunity to study separately how different ecological pressures contribute to toxin diversification. Here, we report the extraordinary defensive strategy of the Rhizoconus subgenus of cone snails. The defensive venom from this worm-hunting subgenus is unusually simple, almost exclusively composed of αD-conotoxins instead of the ubiquitous αA-conotoxins found in the more complex defensive venom of mollusc- and fish-hunting cone snails. A similarly compartmentalized venom gland as those observed in the other dietary groups facilitates the deployment of this defensive venom. Transcriptomic analysis of a Conus vexillum venom gland revealed the αD-conotoxins as the major transcripts, with lower amounts of 15 known and four new conotoxin superfamilies also detected with likely roles in prey capture. Our phylogenetic and molecular evolution analysis of the αD-conotoxins from five subgenera of cone snails suggests they evolved episodically as part of a defensive strategy in the Rhizoconus subgenus. Thus, our results demonstrate an important role for defence in the evolution of conotoxins.


Assuntos
Conotoxinas/química , Caramujo Conus/genética , Evolução Molecular , Filogenia , Transcriptoma , Sequência de Aminoácidos , Animais , Austrália , Linhagem Celular , Conotoxinas/genética , Humanos , Dados de Sequência Molecular , Análise de Sequência de RNA , Espectrometria de Massas em Tandem
4.
Nat Genet ; 25(4): 410-3, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10932184

RESUMO

Mutations in BRCA1 (ref. 1) confer an increased risk of female breast cancer. In a genome-wide scan of linkage disequilibrium (LD), a high level of LD was detected among microsatellite markers flanking BRCA1 (ref. 3), raising the prospect that positive natural selection may have acted on this gene. We have used the predictions of evolutionary genetic theory to investigate this further. Using phylogeny-based maximum likelihood analysis of the BRCA1 sequences from primates and other mammals, we found that the ratios of replacement to silent nucleotide substitutions on the human and chimpanzee lineages were not different from one another (P=0.8), were different from those of other primate lineages (P=0.004) and were greater than 1 (P=0.04). This is consistent with the historic occurrence of positive darwinian selection pressure on the BRCA1 protein in the human and chimpanzee lineages. Analysis of genetic variation in a sample of female Australians of Northern European origin showed evidence for Hardy-Weinberg (HW) disequilibrium at polymorphic sites in BRCA1, consistent with the possibility that natural selection is affecting genotype frequencies in modern Europeans. The clustering of between-species variation in the region of the gene encoding the RAD51-interaction domain of BRCA1 suggests the maintenance of genomic integrity as a possible target of selection.


Assuntos
Evolução Molecular , Genes BRCA1/genética , Adaptação Biológica , Animais , Neoplasias da Mama/genética , Feminino , Variação Genética , Genótipo , Humanos , Funções Verossimilhança , Mutação , Pan troglodytes , Filogenia , Polimorfismo Genético
5.
Mol Cell Biol ; 18(8): 4872-82, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9671496

RESUMO

The c-Cbl protein is tyrosine phosphorylated and forms complexes with a wide range of signalling partners in response to various growth factors. How c-Cbl interacts with proteins, such as Grb2, phosphatidylinositol 3-kinase, and phosphorylated receptors, is well understood, but its role in these complexes is unclear. Recently, the Caenorhabditis elegans Cbl homolog, Sli-1, was shown to act as a negative regulator of epidermal growth factor receptor signalling. This finding forced a reassessment of the role of Cbl proteins and highlighted the desirability of testing genetically whether c-Cbl acts as a negative regulator of mammalian signalling. Here we investigate the role of c-Cbl in development and homeostasis in mice by targeted disruption of the c-Cbl locus. c-Cbl-deficient mice were viable, fertile, and outwardly normal in appearance. Bone development and remodelling also appeared normal in c-Cbl mutants, despite a previously reported requirement for c-Cbl in osteoclast function. However, consistent with a high level of expression of c-Cbl in the hemopoietic compartment, c-Cbl-deficient mice displayed marked changes in their hemopoietic profiles, including altered T-cell receptor expression, lymphoid hyperplasia, and primary splenic extramedullary hemopoiesis. The mammary fat pads of mutant female mice also showed increased ductal density and branching compared to those of their wild-type littermates, indicating an unanticipated role for c-Cbl in regulating mammary growth. Collectively, the hyperplastic histological changes seen in c-Cbl mutant mice are indicative of a normal role for c-Cbl in negatively regulating signalling events that control cell growth. Consistent with this view, we observed greatly increased intracellular protein tyrosine phosphorylation in thymocytes following CD3epsilon cross-linking. In particular, phosphorylation of ZAP-70 kinase in thymocytes was uncoupled from a requirement for CD4-mediated Lck activation. This study provides the first biochemical characterization of any organism that is deficient in a member of this unique protein family. Our findings demonstrate critical roles for c-Cbl in hemopoiesis and in controlling cellular proliferation and signalling by the Syk/ZAP-70 family of protein kinases.


Assuntos
Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/fisiologia , Transdução de Sinais , Ubiquitina-Proteína Ligases , Animais , Desenvolvimento Ósseo , Remodelação Óssea , Complexo CD3/metabolismo , Relação CD4-CD8 , Feminino , Deleção de Genes , Marcação de Genes , Hiperplasia , Masculino , Glândulas Mamárias Animais/citologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-cbl , Esplenomegalia , Timo/citologia , Proteína-Tirosina Quinase ZAP-70
6.
J Natl Cancer Inst ; 90(7): 532-6, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9539249

RESUMO

BACKGROUND: The estrogen receptor (ER) protein is believed to play a role in the development and progression of breast cancer. In a previously published U.S. clinic-based study, a polymorphism in the ER gene (codon 325, CCC --> CCG) was found to be more common in 34 case subjects with a family history of breast cancer than in 154 case subjects without such a history (mean allele frequencies +/- standard error = 0.28+/-0.05 versus 0.11+/-0.02; P<.001). To determine whether this polymorphism is a risk factor for early-onset breast cancer, we conducted a population-based, case-control-family study in Australia. METHODS: Case subjects under the age of 40 years with a first primary breast cancer and control subjects, frequency-matched to the case subjects on the basis of age, and their relatives were interviewed to assess the family history of breast cancer. Polymorphism status of the ER gene was determined for 388 case subjects and 294 control subjects. All statistical tests were two-tailed. RESULTS: There was no association between ER gene polymorphism status and breast cancer, before or after adjustment for risk factors. There was no difference in allele frequencies between case subjects and control subjects (0.232+/-0.015 versus 0.209+/-0.017; P = .4) or between women with and without a family history of breast cancer (P = .3), irrespective of case-control status. The findings were not altered when different definitions of family history of breast cancer were used and when allele frequencies were adjusted for residence and country of birth. CONCLUSION: We found no evidence that the ER codon 325 polymorphism is associated with breast cancer before the age of 40 years or with a family history of breast cancer, despite ample power to detect effects half the magnitude of those previously reported.


Assuntos
Neoplasias da Mama/genética , Códon/genética , Polimorfismo Genético , Receptores de Estrogênio/genética , Adulto , Alelos , Austrália , Neoplasias da Mama/metabolismo , Estudos de Casos e Controles , Primers do DNA , Feminino , Humanos , Razão de Chances
7.
J Natl Cancer Inst ; 91(24): 2107-11, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10601382

RESUMO

BACKGROUND: A recent meta-analysis of 23 studies supported the empirically derived hypothesis that women who lack one of the four common minisatellite alleles at the HRAS1 locus are at increased risk of breast cancer. These studies relied on visual sizing of alleles on electrophoretic gels and may have underreported rare alleles. We determined whether this hypothesis applied to early-onset breast cancer by using a new method to size minisatellite alleles. METHODS: We conducted a population-based, case-control-family study of 249 Australian women under 40 years old at diagnosis of a first primary breast cancer and 234 randomly selected women, frequency matched for age. We sized HRAS1 minisatellite alleles with an Applied Biosystems model 373 automated DNA sequencer and GENESCAN(TM) software. All P values are two-sided. RESULTS: We found no association of rare alleles with breast cancer, before or after adjustment for risk factors and irrespective of how their effects were modeled (crude odds ratio = 1.04; 95% confidence interval [CI] = 0.071-1.53; P =.8). The rare allele frequency was 0. 173 (95% CI = 0.149-0.197), three times the pooled estimate of 0.058 (95% CI = 0.050-0.066) from previous studies (P<.001), and was similar for case subjects, 0.177 (95% CI = 0.143-0.221), and control subjects, 0.169 (95% CI = 0.135-0.203) (P =.7). CONCLUSION: There was no support for an association between rare HRAS1 alleles and the risk of early-onset breast cancer, despite 80% power to detect effects of the magnitude of those associations (1.7-fold) previously suggested. IMPLICATIONS: The question of whether cancer risk is associated with rare minisatellite HRAS1 alleles needs to be revisited with the use of new methods that have a greater ability to distinguish rare alleles from similarly sized common alleles.


Assuntos
Alelos , Neoplasias da Mama/genética , Repetições Minissatélites , Proteínas Proto-Oncogênicas p21(ras)/genética , Adulto , Austrália , Estudos de Casos e Controles , Feminino , Humanos , Razão de Chances , Distribuição Aleatória
8.
J Natl Cancer Inst ; 92(20): 1674-81, 2000 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-11036113

RESUMO

BACKGROUND: The cytochrome P450c17alpha enzyme functions in the steroid biosynthesis pathway, and altered endogenous steroid hormone levels have been reported to be associated with a T to C polymorphism in the 5' promoter region of the CYP17 gene. Because steroid hormone exposure is known to influence breast cancer risk, we conducted a population-based, case-control-family study to assess the relationship between the CYP17 promoter polymorphism and early-onset breast cancer. METHODS: Case subjects under 40 years of age at diagnosis of a first primary breast cancer, population-sampled control subjects, and the relatives of both case and control subjects were interviewed to record family history of breast cancer and other risk factors. CYP17 genotype was determined in 369 case subjects, 284 control subjects, and 91 relatives of case subjects. Genotype distributions were compared by logistic regression, and cumulative risk was estimated by a modified segregation analysis. All statistical tests were two-tailed. RESULTS: Compared with the TT genotype (i.e., individuals homozygous for the T allele), the TC genotype was not associated with increased breast cancer risk (P: =.7). Compared with the TT and TC genotypes combined, the CC genotype was associated with a relative risk of 1. 81 (95% confidence interval [CI] = 1.15-2.86; P: =.01) before adjustment for measured risk factors and 1.63 (95% CI = 1.00-2.64; P: =.05) after adjustment. There was an excess of CC genotypes in case subjects who had at least one affected first- or second-degree relative, compared with control subjects unstratified by family history of breast cancer (23% versus 11%; P: =.006), and these case subjects had a threefold to fourfold higher risk than women of other groups defined by genotype and family history of breast cancer. Analysis of breast cancer in first- and second-degree relatives of case subjects with the CC genotype, excluding two known carriers of a deleterious mutation in BRCA1 or BRCA2, gave a relative hazard in women with the CC genotype of 3.48 (95% CI = 1.13-10.74; P: =.04), which is equivalent to a cumulative risk of 16% to age 70 years. CONCLUSIONS: The CC genotype may modify the effect of other familial risk factors for early-onset breast cancer.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Polimorfismo Genético , Esteroide 17-alfa-Hidroxilase/genética , Adulto , Fatores Etários , Idade de Início , Alelos , Austrália , Estudos de Casos e Controles , Primers do DNA , DNA de Neoplasias/análise , Feminino , Genes BRCA1/genética , Genes Supressores de Tumor/genética , Genótipo , Humanos , Modelos Logísticos , Mutação , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética , Risco
9.
J Natl Cancer Inst ; 91(11): 961-6, 1999 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-10359549

RESUMO

BACKGROUND: We conducted a population-based, case-control-family study to determine whether androgen receptor (AR) exon 1 polymorphic CAG repeat length (CAGn) was a risk factor for early-onset breast cancer in the Australian population. METHODS: Case subjects under 40 years of age at diagnosis of a first primary breast cancer and age-matched control subjects were interviewed to assess family history and other risk factors. AR CAGn length was determined for 368 case subjects and 284 control subjects. Distributions in the two groups were compared by linear and logistic regression, allowing adjustment for measured risk factors. All statistical tests were two-tailed. RESULTS: When analyzed as either a continuous or a dichotomous variable, there was no association between CAG, length and breast cancer risk, before or after adjustment for risk factors. Mean (95% confidence interval [CI]) CAGn lengths were 22.0 (21.8-22.2) for case subjects and 22.0 (21.7-22.3) for control subjects (P = .9). The frequency (95% CI) of alleles with 22 or more CAGn repeats was 0.531 (0.494-0.568) for case subjects and 0.507 (0.465-0.549) for control subjects (P = .4). After adjustment, the average effect on log OR (odds ratio) per allele was 0.16 (95% CI = -0.03 to 0.40; P = .2), and the effect of any allele was equivalent to an OR of 1.40 (95% CI = 0.94-2.09; P = .1). Stratification by family history also failed to reveal any association. Similar results were obtained when alleles were defined by other cutoff points. CONCLUSION: We found no evidence for an association between AR exon 1 CAGn length and breast cancer risk in women under the age of 40, despite having 80% power to detect modest effects.


Assuntos
Neoplasias da Mama/metabolismo , Éxons/genética , Receptores Androgênicos/genética , Repetições de Trinucleotídeos/genética , Adulto , Idade de Início , Austrália , Neoplasias da Mama/genética , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Imuno-Histoquímica , Modelos Lineares , Modelos Logísticos , Razão de Chances , Polimorfismo Genético , Fatores de Risco
10.
Cancer Res ; 61(3): 903-7, 2001 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11221879

RESUMO

The gene for the steroid receptor coactivator amplified in breast cancer 1 (AIBI), located on chromosome 20q12, is overexpressed at the mRNA level in up to 60% of primary breast carcinomas; however, only 5% of these tumors show DNA amplification. The transcription factors and signaling pathways relevant to breast cancer, which in the absence of DNA amplification are responsible for and targeted by elevated levels of AIBI mRNA, are unknown. In the present study, in situ hybridization was used to examine AIB1 mRNA expression in 93 breast carcinomas of varying histological grade and immunohistochemical profile. AIB1 mRNA was overexpressed relative to normal breast tissue in 26 of 83 (31%) invasive tumors. This was found to associate with high tumor grade (P = 0.0006), lack of immunohistochemical staining for the steroid receptors estrogen receptor (P = 0.002) and progesterone receptor (P = 0.002), and strong protein staining for p53 (P = 0.01) and HER2/neu (P = 0.002). These findings suggest that AIB1 overexpression may impact on breast cancer by a mechanism not wholly dependent on steroid receptor coexpression and which may involve other oncogenic events, such as p53 protein stabilization and HER2/neu overexpression.


Assuntos
Neoplasias da Mama/metabolismo , Receptor ErbB-2/biossíntese , Receptores de Estrogênio/biossíntese , Receptores de Progesterona/biossíntese , Fatores de Transcrição/biossíntese , Proteína Supressora de Tumor p53/biossíntese , Adulto , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , Pessoa de Meia-Idade , Coativador 3 de Receptor Nuclear , Antígeno Prostático Específico/biossíntese , Antígeno Prostático Específico/genética , Biossíntese de Proteínas , Proteínas/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Fatores de Transcrição/genética , Fator Trefoil-1 , Proteínas Supressoras de Tumor
11.
Cancer Res ; 59(8): 2011-7, 1999 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10213514

RESUMO

Breast cancers arising in women with and without a germline mutation in the BRCA1 or BRCA2 gene display different histological features, which suggests unique mechanisms of molecular pathogenesis: We used a molecular pathological analysis to define the genetic abnormalities relevant to these specific pathogeneses. Tumor material was studied from 40 women with breast cancer diagnosed before 40 years of age, sampled from a population-based study and stratified by BRCA1 and BRCA2 germline mutation status. Cases were not selected for family history or ethnic origin, and none were known to be genetically related. Thus, germline mutation itself is likely to impact on the molecular pathogenesis of these tumors, with no substantial influence due to modifying genetic or environmental factors. Breast cancers occurring in BRCA1 mutation carriers had significantly higher levels of p53 expression, including the preinvasive (carcinoma in situ) stage of disease, compared with cancers occurring in BRCA2 mutation carriers or women with no detectable germline mutation. These cancers also had a higher proliferation rate as measured by Ki-67 antibody. Expression of the prognostic factors c-erbB-2, cyclin D1, and estrogen receptor was significantly less common in BRCA1 mutation carriers. Lower levels of cyclin D1 were also found in cancers from BRCA2 mutation carriers compared with non-mutation carriers. Direct p53 mutation analysis revealed mutations in 18% of all of the early-onset breast cancers within the study and included rare insertion and deletional mutations in cancers from BRCA1 mutation carriers. Our data indicate that a BRCA1 breast cancer phenotype may be recognized by an exceptionally high proliferation rate and early and frequent p53 overexpression but infrequent selection for overexpression of several other prognostic factor proteins known to be involved in breast oncogenesis. In contrast, breast cancers arising in BRCA2 mutation carriers have a more heterogeneous phenotypic profile.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Proteínas de Neoplasias/genética , Fatores de Transcrição/genética , Idade de Início , Proteína BRCA2 , Neoplasias da Mama/patologia , Neoplasias da Mama/fisiopatologia , Feminino , Genética Populacional , Humanos , Imuno-Histoquímica , Perda de Heterozigosidade , Mutação , Invasividade Neoplásica/genética , Proteína Supressora de Tumor p53/genética
12.
Oncogene ; 6(3): 445-8, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2011399

RESUMO

The retinoblastoma susceptibility gene, RB, is the best characterised of the tumour suppressor genes, or 'anti-oncogenes'. Abnormal function of the RB protein is thought to result in loss of an inhibitory effect on cell growth, and thus contribute towards the development of certain human cancers. One group of human cancers of particular interest in relationship to retinoblastoma gene function are the gliomas, which are central nervous system tumours thought to originate from the neuroectoderm, the embryological tissue which also gives rise to retinoblastomas. We have therefore examined a group of benign and malignant gliomas for evidence of structural alterations of the RB gene. Four out of nine (44%) glioblastomas, the most malignant gliomas, showed loss of heterozygosity of a locus within this gene. In addition, one of these hemizygous tumours showed deletion of part of the RB protein-coding region, and this abnormality was also present in cells cultured from the tumour. These findings suggest that RB gene abnormalities may contribute to the development of glioblastomas.


Assuntos
Deleção Cromossômica , Proteína do Retinoblastoma/genética , Retinoblastoma/genética , Alelos , Northern Blotting , Southern Blotting , DNA/genética , Sondas de DNA , Genes do Retinoblastoma , Células HeLa , Heterozigoto , Homozigoto , Humanos , RNA Mensageiro/análise , RNA Mensageiro/genética
13.
Biochim Biophys Acta ; 1263(3): 266-70, 1995 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-7548217

RESUMO

The gene for the sheep arginine vasopressin type 1a (V1a) receptor subtype was cloned from a genomic library. The deduced amino acid sequence shows characteristics of a G-protein coupled receptor and high sequence identity to human and rat V1a receptor sequences (81% and 73%, respectively). Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed a tissue distribution consistent with a type V1a receptor. The genomic DNA (7.1 kb) contains a 1586 bp intron between the putative 6th and 7th transmembrane domains.


Assuntos
Receptores de Vasopressinas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA/química , Biblioteca Genômica , Dados de Sequência Molecular , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Ovinos
14.
Biochim Biophys Acta ; 1309(1-2): 77-80, 1996 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-8950181

RESUMO

A novel human P2 nucleotide receptor has been cloned from a T-cell cDNA library. The predicted amino acid sequence shows characteristics of a G-protein-coupled receptor, and shares 88% homology with a recently characterised rat P2 nucleotide receptor sequence. Distinctive features include an extremely short cytoplasmic tail with only one putative protein kinase C phosphorylation site. Northern blot analysis revealed a 1.9 kb transcript expressed in the placenta.


Assuntos
DNA Complementar/genética , Receptores Purinérgicos P2/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Proteínas de Ligação ao GTP , Humanos , Dados de Sequência Molecular , Especificidade de Órgãos , RNA Mensageiro/análise , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Linfócitos T
15.
Hum Mutat ; 22(1): 86-91, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12815598

RESUMO

Genetic testing for cancer predisposing mutations in BRCA1 and BRCA2 has been of benefit to many individuals from breast and ovarian cancer-prone kindreds. However, a function has not been assigned to many of the domains that make up these complex proteins and hence, the significance of many sequence variants, including missense mutations, splice-site mutations, and in-frame deletions/insertions, remains unclear. We identified a putative splice site mutation (IVS6-2delA) in BRCA1 in a family attending a Familial Cancer Centre that had a significant history of both breast and ovarian cancer. This sequence variant was not novel but the exact effect on mRNA splicing and hence the biological impact of this sequence variation was unclear and therefore the finding was unable to be used in genetic counseling of the family. Via the construction of novel GFP-based expression fusion constructs, we demonstrated that this sequence variation prevented normal splicing of the BRCA1 transcript. By combining these data with an assessment of the histopathological features of the breast carcinomas in this family and mutation penetrance estimate we were able to conclude that this BRCA1 variant conveyed an increased risk of breast cancer.


Assuntos
Proteína BRCA1/genética , Proteínas Luminescentes/biossíntese , Mutação , Penetrância , Sítios de Splice de RNA/genética , Adulto , Idoso , Processamento Alternativo/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , DNA Complementar/genética , Feminino , Genes BRCA1 , Triagem de Portadores Genéticos/métodos , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Proteínas de Fluorescência Verde , Humanos , Proteínas Luminescentes/genética , Masculino , Pessoa de Meia-Idade , Neoplasias Ovarianas/genética , Linhagem , RNA Neoplásico/análise
16.
J Natl Cancer Inst Monogr ; (26): 95-100, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10854492

RESUMO

BACKGROUND: Historically, studies of the "genetic epidemiology" of cancer have used nonsystematically sampled kindreds with numerous cases of cancer across multiple generations. From the epidemiologic viewpoint, it is difficult to extrapolate findings to the population because of the ad hoc ascertainment of these atypical, ill-defined families. Since 1992, we have been conducting a population-based, case-control-family study of breast cancer. METHODS: Families are identified through a single, population-sampled proband, who is either affected or unaffected, making adjustment for ascertainment straightforward. Administered questionnaires and blood samples are sought from cases, controls, and specified sets of relatives. From 1996 through 1999, a further 1200 case families have been recruited as part of the Co-operative Family Registry for Breast Cancer Studies (CFRBCS). Issues relevant to the study design and analysis are discussed. RESULTS: Epidemiologic and genetic findings published to date are summarized. In particular, this population-based study has shown that the so-called "high-risk" families containing multiple cases of breast cancer are not typical of families in the general population in which BRCA1 or BRCA2 mutations are segregating. Most "hereditary" cancers are "sporadic." CONCLUSION: The collection of DNA, as well as data on disease status and risk factors, from population-sampled sets of relatives provides a powerful resource for addressing genetic and environmental determinants of cancer. A population-based multicenter, multidisciplinary enterprise, such as has been developed by the CFRBCS, may become a model for future research in cancer epidemiology, allowing genetic and environmental risk factors to be put into a proper population perspective.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Predisposição Genética para Doença , Sistema de Registros , Projetos de Pesquisa , Estudos de Casos e Controles , Família , Feminino , Humanos
17.
Cancer Epidemiol Biomarkers Prev ; 8(9): 741-7, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10498392

RESUMO

The average breast cancer risk for carriers of a germ-line mutation in BRCA1 or BRCA2 (penetrance) has been estimated from the multiple-case families collected by the Breast Cancer Linkage Consortium (BCLC) to be approximately 80% to age 70. However, women now being tested for these mutations do not necessarily have the intense family history of the BCLC families. Testing for protein-truncating mutations in exons 2, 11, and 20 of BRCA1 and exons 10 and 11 of BRCA2 was conducted in a population-based sample of 388 Australian women with breast cancer diagnosed before age 40. Onset of breast cancer was analyzed in the known and potential mutation-carrying first- and second-degree female relatives of cases found to carry a mutation. Of the 18 mutation-carrying cases (9 BRCA1 and 9 BRCA2), only 5 (1 BRCA1 and 4 BRCA2) had at least one affected relative, so family history of breast cancer was not a strong predictor of mutation status in this setting. The risk in mutation carriers was, on average, 9 times the population risk [95% confidence interval (CI), 4-23; P < 0.001]. Penetrance to age 70 was 40% (95% CI, 15-65%), about half that estimated from BCLC families. By extrapolation, approximately 6% (95% CI, 2-20%) of breast cancer before age 40 may be caused by protein-truncating mutations in BRCA1 or BRCA2. Breast cancer risk in BRCA1 or BRCA2 mutation carriers may be modified by other genetic or environmental factors. Genetic counselors may need to take into account the family history of the consultand.


Assuntos
Neoplasias da Mama/epidemiologia , Genes Supressores de Tumor/genética , Predisposição Genética para Doença , Mutação , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Proteína BRCA2 , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Estudos de Casos e Controles , Primers do DNA , Feminino , Genes BRCA1/genética , Predisposição Genética para Doença/genética , Heterozigoto , Humanos , Funções Verossimilhança , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Reação em Cadeia da Polimerase , Medição de Risco , Fatores de Transcrição/genética
18.
Cancer Epidemiol Biomarkers Prev ; 10(12): 1287-93, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11751447

RESUMO

The enzyme 5alpha-reductase type II (SRD5A2) converts testosterone to its more active form 5alpha-dihydroxytestosterone. The 3' untranslated region of the gene contains a (TA)(n) length polymorphism. The (TA)(9) allele has been reported to be associated with higher serum prostate-specific antigen levels in breast tumors and lower risk of relapse in breast cancer patients and more recently has also been reported to be linked to the codon 89 valine variant, which is itself associated with higher serum prostate-specific antigen levels in breast tumors and a more favorable breast cancer prognosis. We investigated whether the SRD5A2 (TA)(n) polymorphism was associated with risk of breast or ovarian cancer in Australian women by studying 946 breast cancer cases and 509 age-matched controls, and 544 ovarian cancer cases and 298 controls of similar age distribution. The (TA)(9) allele frequency was similar in breast cancer cases (0.110), breast cancer controls (0.125), ovarian cancer cases (0.106), and ovarian cancer controls (0.117). There was no difference in genotype distribution between breast cancer cases and controls (P = 0.5), ovarian cancer cases and controls (P = 0.7), or between the two control groups (P = 0.9). Genotypes containing at least one (TA)(9) allele were not significantly associated with risk of breast cancer overall (odds ratio, 0.86; 95% confidence interval, 0.67-1.12; P = 0.3) or in women stratified by age, menopausal status, or family history. Similarly, the (TA)(9) allele was not associated with risk of ovarian cancer (odds ratio, 0.87; 95% confidence interval, 0.61-1.23; P = 0.4) or with ovarian tumor behavior (invasive or low malignant potential), histology, stage, or grade. Given that this study had sufficient power to detect altered risks in the order of 1.4- to 1.7-fold, our results suggest that the SRD5A2 (TA)(9) allele is unlikely to be associated with moderate alterations in breast or ovarian cancer risk.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Neoplasias da Mama/genética , Predisposição Genética para Doença , Neoplasias Ovarianas/genética , Polimorfismo Genético , Adulto , Fatores Etários , Austrália/epidemiologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Menopausa , Pessoa de Meia-Idade , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/etiologia , Fatores de Risco
19.
Eur J Cancer ; 39(5): 622-30, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12628841

RESUMO

The optimal management of ductal carcinoma in situ (DCIS) is controversial, due in part to our poor understanding of its natural history. We undertook to identify subgroups of DCIS based on the expression of biomarkers, which were related to the likelihood of clinical recurrence. Biomarker expression of a total of 95 DCIS lesions in a nested case-control study within a population-based cohort with up to 135 months follow-up data (median 101 months) was analysed using immunohistochemistry. ERBB2-positivity and bcl-2-, oestrogen receptor (ER)- and progesterone receptor (PR)-negativity were individually associated with the risk of clinical recurrence. The predictive value of these biomarkers was independent of cytonuclear grade. ERBB2, bcl-2, ER and PR expression were conserved in the recurrent lesions, including subsequent invasive cancers. p21-positive DCIS was also associated with clinical recurrence, independently of the associations with ERBB2/bcl-2/ER/PR expression. These data identify clinically and biologically relevant subcategories of DCIS lesions, an essential basis for improving management.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Carcinoma Intraductal não Infiltrante/diagnóstico , Recidiva Local de Neoplasia/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/química , Carcinoma Intraductal não Infiltrante/química , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/química , Valor Preditivo dos Testes , Receptor ErbB-2/metabolismo
20.
Am J Surg Pathol ; 22(11): 1423-8, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9808136

RESUMO

The occurrence of Epstein-Barr virus-associated smooth-muscle tumors in immunocompromised patients has been reported, particularly in the pediatric population. In posttransplantation tumors, the tissue of origin has been either donor or recipient. Mixed-genotype sarcomas within the same patient have not yet been reported. We describe the occurrence of multiple leiomyosarcomas of both donor (arising in the lung allograft) and recipient (arising in the host liver) origin in a 15-year-old boy 3 years after heart-lung transplantation. Analysis of premortem lung tumors demonstrated the presence of Epstein-Barr virus DNA. Despite decreasing immunosuppression and commencing acyclovir, the patient died of systemic Pseudomonas infection. Immunohistochemical analysis revealed that both lung and liver tumors were negative for the Epstein-Barr virus receptor (CD21), and suggests that Epstein-Barr virus entry into the cells was not via this receptor but via an alternate mechanism such as cell fusion.


Assuntos
Transplante de Coração-Pulmão , Leiomiossarcoma/patologia , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/patologia , Neoplasias Primárias Múltiplas/patologia , Adolescente , Impressões Digitais de DNA , DNA de Neoplasias/análise , DNA Viral/análise , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/patologia , Evolução Fatal , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Humanos , Imuno-Histoquímica , Terapia de Imunossupressão , Leiomiossarcoma/virologia , Neoplasias Hepáticas/química , Neoplasias Hepáticas/virologia , Neoplasias Pulmonares/química , Neoplasias Pulmonares/virologia , Masculino , Repetições de Microssatélites , Neoplasias Primárias Múltiplas/química , Reação em Cadeia da Polimerase , Receptores de Complemento 3d/análise , Doadores de Tecidos
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