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1.
Cell ; 187(2): 257-270, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38242082

RESUMO

The view of organelles and how they operate together has changed dramatically over the last two decades. The textbook view of organelles was that they operated largely independently and were connected by vesicular trafficking and the diffusion of signals through the cytoplasm. We now know that all organelles make functional close contacts with one another, often called membrane contact sites. The study of these sites has moved to center stage in cell biology as it has become clear that they play critical roles in healthy and developing cells and during cell stress and disease states. Contact sites have important roles in intracellular signaling, lipid metabolism, motor-protein-mediated membrane dynamics, organelle division, and organelle biogenesis. Here, we summarize the major conceptual changes that have occurred in cell biology as we have come to appreciate how contact sites integrate the activities of organelles.


Assuntos
Organelas , Biologia , Membrana Celular/metabolismo , Membranas Mitocondriais , Organelas/química , Organelas/metabolismo , Membranas Intracelulares/química , Membranas Intracelulares/metabolismo
2.
Nucleic Acids Res ; 50(5): 2959-2972, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35212369

RESUMO

G-quadruplexes (GQs) are non-canonical DNA structures composed of stacks of stabilized G-tetrads. GQs play an important role in a variety of biological processes and may form at telomeres and oncogene promoters among other genomic locations. Here, we investigate nine variants of telomeric DNA from Tetrahymena thermophila with the repeat (TTGGGG)n. Biophysical data indicate that the sequences fold into stable four-tetrad GQs which adopt multiple conformations according to native PAGE. Excitingly, we solved the crystal structure of two variants, TET25 and TET26. The two variants differ by the presence of a 3'-T yet adopt different GQ conformations. TET25 forms a hybrid [3 + 1] GQ and exhibits a rare 5'-top snapback feature. Consequently, TET25 contains four loops: three lateral (TT, TT, and GTT) and one propeller (TT). TET26 folds into a parallel GQ with three TT propeller loops. To the best of our knowledge, TET25 and TET26 are the first reported hybrid and parallel four-tetrad unimolecular GQ structures. The results presented here expand the repertoire of available GQ structures and provide insight into the intricacy and plasticity of the 3D architecture adopted by telomeric repeats from T. thermophila and GQs in general.


Assuntos
Quadruplex G , DNA/química , DNA/genética , Conformação de Ácido Nucleico , Telômero/genética
3.
Angew Chem Int Ed Engl ; 62(26): e202301666, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-36995904

RESUMO

An i-motif is a non-canonical DNA structure implicated in gene regulation and linked to cancers. The C-rich strand of the HRAS oncogene, 5'-CGCCCGTGCCCTGCGCCCGCAACCCGA-3' (herein referred to as iHRAS), forms an i-motif in vitro but its exact structure was unknown. HRAS is a member of the RAS proto-oncogene family. About 19 % of US cancer patients carry mutations in RAS genes. We solved the structure of iHRAS at 1.77 Šresolution. The structure reveals that iHRAS folds into a double hairpin. The two double hairpins associate in an antiparallel fashion, forming an i-motif dimer capped by two loops on each end and linked by a connecting region. Six C-C+ base pairs form each i-motif core, and the core regions are extended by a G-G base pair and a cytosine stacking. Extensive canonical and non-canonical base pairing and stacking stabilizes the connecting region and loops. The iHRAS structure is the first atomic resolution structure of an i-motif from a human oncogene. This structure sheds light on i-motifs folding and function in the cell.


Assuntos
DNA , Oncogenes , Humanos , Conformação de Ácido Nucleico , Pareamento de Bases , DNA/química , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas p21(ras)/genética
4.
Ann Oncol ; 33(8): 769-785, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35605746

RESUMO

BACKGROUND: Invasive lobular breast cancer (ILC) is the second most common type of breast cancer after invasive breast cancer of no special type (NST), representing up to 15% of all breast cancers. DESIGN: Latest data on ILC are presented, focusing on diagnosis, molecular make-up according to the European Society for Medical Oncology Scale for Clinical Actionability of molecular Targets (ESCAT) guidelines, treatment in the early and metastatic setting and ILC-focused clinical trials. RESULTS: At the imaging level, magnetic resonance imaging-based and novel positron emission tomography/computed tomography-based techniques can overcome the limitations of currently used imaging techniques for diagnosing ILC. At the pathology level, E-cadherin immunohistochemistry could help improving inter-pathologist agreement. The majority of patients with ILC do not seem to benefit as much from (neo-)adjuvant chemotherapy as patients with NST, although chemotherapy might be required in a subset of high-risk patients. No differences in treatment efficacy are seen for anti-human epidermal growth factor receptor 2 (HER2) therapies in the adjuvant setting and cyclin-dependent kinases 4 and 6 inhibitors in the metastatic setting. The clinical utility of the commercially available prognostic gene expression-based tests is unclear for patients with ILC. Several ESCAT alterations differ in frequency between ILC and NST. Germline BRCA1 and PALB2 alterations are less frequent in patients with ILC, while germline CDH1 (gene coding for E-cadherin) alterations are more frequent in patients with ILC. Somatic HER2 mutations are more frequent in ILC, especially in metastases (15% ILC versus 5% NST). A high tumour mutational burden, relevant for immune checkpoint inhibition, is more frequent in ILC metastases (16%) than in NST metastases (5%). Tumours with somatic inactivating CDH1 mutations may be vulnerable for treatment with ROS1 inhibitors, a concept currently investigated in early and metastatic ILC. CONCLUSION: ILC is a unique malignancy based on its pathological and biological features leading to differences in diagnosis as well as in treatment response, resistance and targets as compared to NST.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Lobular , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Caderinas/uso terapêutico , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/diagnóstico , Carcinoma Lobular/genética , Carcinoma Lobular/terapia , Feminino , Humanos , Prognóstico , Proteínas Proto-Oncogênicas
5.
BMC Cancer ; 20(1): 187, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32178645

RESUMO

BACKGROUND: The burden of disease due to cancer remains substantial. Since the value of real-world evidence has also been recognised by regulatory agencies, we established a Research Ethics Committee (REC) approved research database for cancer patients (Reference: 18/NW/0297). CONSTRUCTION AND CONTENT: Guy's Cancer Cohort introduces the concept of opt-out consent processes for research in a subset of oncology patients diagnosed and treated at a large NHS Trust in the UK. From April 2016 until March 2017, 1388 eligible patients visited Guy's and St Thomas' NHS Foundation Trust (GSTT) for breast cancer management. For urological cancers this number was 1757 and for lung cancer 677. The Cohort consists of a large repository of routinely collected clinical data recorded both retrospectively and prospectively. The database contains detailed clinical information collected at various timepoints across the treatment pathway inclusive of diagnostic data, and data on disease progression, recurrence and survival. CONCLUSIONS: Guy's Cancer Cohort provides a valuable infrastructure to answer a wide variety of research questions of a clinical, mechanistic, and supportive care nature. Clinical research using this database will result in improved patient safety and experience. Guy's Cancer Cohort promotes collaborative research and will accept applications for the release of anonymised datasets for research purposes.


Assuntos
Neoplasias da Mama , Bases de Dados Factuais , Neoplasias Pulmonares , Neoplasias Urológicas , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Progressão da Doença , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/terapia , Masculino , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/terapia , Neoplasias Urológicas/diagnóstico , Neoplasias Urológicas/mortalidade , Neoplasias Urológicas/terapia
7.
Ultrasound Obstet Gynecol ; 49(2): 171-176, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27731538

RESUMO

OBJECTIVE: Methotrexate is used routinely worldwide for the medical treatment of clinically stable women with a tubal ectopic pregnancy. This is despite the lack of robust evidence to show its superior effectiveness over expectant management. The aim of our multicenter randomized controlled trial was to compare success rates of methotrexate against placebo for the conservative treatment of tubal ectopic pregnancy. METHODS: This study took place in two early-pregnancy units in the UK between August 2005 and June 2014. Inclusion criteria were clinically stable women with a conclusive ultrasound diagnosis of a tubal ectopic pregnancy, presenting with a low serum beta human chorionic gonadotropin (ß-hCG) level of < 1500 IU/L. Women were assigned randomly to a single systemic injection of either 50 mg/m2 methotrexate or placebo. The primary outcome was a binary indicator for success of conservative management, defined as resolution of clinical symptoms and decline of serum ß-hCG to < 20 IU/L or a negative urine pregnancy test without the need for any additional medical intervention. An intention-to-treat analysis was followed. RESULTS: We recruited a total of 80 women, 42 of whom were assigned to methotrexate and 38 to placebo. The arms of the study were matched in terms of age, ethnicity, obstetric history, pregnancy characteristics and serum levels of ß-hCG and progesterone. The rates of success were similar for the two study arms: 83% with methotrexate and 76% with placebo. On univariate analysis, this difference was not statistically significant (χ2 (1 degree of freedom) = 0.53; P = 0.47). On multivariate logistic regression, the serum level of ß-hCG was the only covariate found to be significantly associated with outcome. The odds of failure increased by 0.15% for each unit increase in ß-hCG (odds ratio, 1.0015 (95% CI, 1.0002-1.003); P = 0.02). In 14 women presenting with serum ß-hCG of 1000-1500 IU/L, the success rate was 33% in those managed expectantly compared with 62% in those receiving methotrexate. This difference was not statistically significant and a larger sample size would be needed to give sufficient power to detect a difference in the subgroup of women with higher ß-hCG. In women with successful conservative treatment, there was no significant difference in median ß-hCG resolution times between study arms (17.5 (interquartile range (IQR), 14-28.0) days (n = 30) in the methotrexate group vs 14 (IQR, 7-29.5) days (n = 25) in the placebo group; P = 0.73). CONCLUSIONS: The results of our study do not support the routine use of methotrexate for the treatment of clinically stable women diagnosed with tubal ectopic pregnancy presenting with low serum ß-hCG (< 1500 IU/L). Further work is required to identify a subgroup of women with tubal ectopic pregnancy and ß-hCG ≥ 1500 IU/L in whom methotrexate may offer a safe and cost-effective alternative to surgery. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Comparación entre una sola dosis de metotrexate sistémico y la conducta expectante en el tratamiento de casos de embarazo ectópico tubárico: un ensayo aleatorio controlado con placebo RESUMEN OBJETIVO: El metotrexate se utiliza de modo rutinario en todo el mundo para el tratamiento de las mujeres clínicamente estables con un embarazo ectópico tubárico. Esto sucede a pesar de la falta de evidencia rigurosa que demuestre que su eficacia es superior a la conducta expectante. El objetivo de este ensayo controlado aleatorio multicéntrico fue comparar las tasas de éxito del metotrexate con las de un placebo para el tratamiento cauteloso del embarazo ectópico tubárico. MÉTODOS: Este estudio se llevó a cabo en dos clínicas de control de gestación temprana en el Reino Unido entre agosto de 2005 y junio de 2014. Los criterios de inclusión fueron mujeres clínicamente estables con un diagnóstico ecográfico concluyente de embarazo ectópico tubárico, las cuáles presentaban una concentración sérica baja de la ß hormona coriónica gonadotrópica (ß-hCG) inferior a 1500 UI/L. Las mujeres fueron asignadas aleatoriamente a una sola inyección sistémica de 50 mg/m2 de metotrexate o a placebo. El resultado primario fue un indicador binario del éxito del tratamiento conservador, definido como la resolución de los síntomas clínicos y la disminución en el suero de la ß-hCG a <20 UI/L o una prueba de embarazo negativa en orina sin la necesidad de ninguna intervención médica adicional. Se hizo un análisis por intención de tratar. RESULTADOS: Se reclutó un total de 80 mujeres; a 42 de ellas se les asignó el metotrexate y a 38 el placebo. Los grupos del estudio se realizaron en función de la edad, el origen étnico, los antecedentes obstétricos, las características del embarazo y los niveles séricos de la ß-hCG y la progesterona. Las tasas de éxito fueron similares para los dos grupos de estudio: 83% con metotrexate y 76% con placebo. En el análisis univariante, esta diferencia no fue estadísticamente significativa (χ2 (1 grado de libertad) = 0,53; P = 0,47). En la regresión logística multivariante, el nivel sérico de la ß-hCG fue la única covariable que se encontró significativamente asociada con el resultado. Las probabilidades de fracaso aumentaron en un 0,15% por cada unidad de aumento de la ß-hCG (cociente de probabilidad 1,0015 (IC 95%, 1,0002-1,003); P = 0,02). La tasa de éxito en las 14 mujeres con un nivel sérico de la ß-hCG de 1000-1500 UI/L fue del 33% en las tratadas con conducta expectante frente al 62% en las que recibieron metotrexate. Esta diferencia no fue estadísticamente significativa, por lo que se necesitaría un tamaño de muestra mayor, lo suficiente como para poder detectar diferencias en el subgrupo de mujeres con una ß-hCG más elevada. En las mujeres en las que el tratamiento conservador tuvo éxito, no hubo una diferencia significativa en la mediana de los tiempos de resolución de la ß-hCG entre los grupos del estudio (17,5 (amplitud intercuartílica (IQR), 14-28,0) días (n = 30) en el grupo de metotrexate frente a 14 (IQR, 7-29.5) días (n = 25) en el grupo de placebo; P = 0,73). CONCLUSIONES: Los resultados de este estudio no apoyan el uso rutinario de metotrexate para el tratamiento de las mujeres clínicamente estables diagnosticadas con un embarazo ectópico tubárico que presenta un nivel sérico bajo la ß-hCG (<1500 UI/L). Serán necesarios estudios adicionales para identificar un subgrupo de mujeres con embarazo ectópico tubárico y ß-hCG ≥1500 UI/L para quienes el metotrexate puede ofrecer una alternativa segura y rentable en comparación con la cirugía. : : ,,。。 : 2005820146,2。,,ß(beta human chorionic gonadotropin,ß-hCG)<1500 IU/L。,(50 mg/m2 )。,ß-hCG<20 IU/L,。。 : 80,42,38。2、、、ß-hCG。2:83%,76%。,[χ2 (1)=0.53;P=0.47]。logistic,ß-hCG。ß-hCG,0.15%[,1.0015(95% CI,1.0002~1.003);P=0.02]。14ß-hCG1000~1500 IU/L,33%,62%。,ß-hCG。,2ß-hCG(P=0.73),17.5[(interquartile range,IQR),14~28.0](n=30),14 (IQR,7~29.5)(n=25)。 : 、、ß-hCG(<1500 IU/L)。,ß-hCG>1500 IU/L、。.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/sangue , Metotrexato/administração & dosagem , Gravidez Tubária/tratamento farmacológico , Gravidez Tubária/cirurgia , Adulto , Feminino , Humanos , Análise de Intenção de Tratamento , Modelos Logísticos , Metotrexato/uso terapêutico , Gravidez , Gravidez Tubária/metabolismo , Resultado do Tratamento , Adulto Jovem
8.
Ann Oncol ; 26(4): 756-761, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25595936

RESUMO

BACKGROUND: A rare recurrent missense variant in HOXB13 (rs138213197/G84E) was recently reported to be associated with hereditary prostate cancer. Population-based studies have established that, since the frequency of this single-nucleotide polymorphism (SNP) varies between geographic regions, the associated proportion of prostate cancer (PrCa) risk contribution is also highly variable by country. PATIENTS AND METHODS: This is the largest comprehensive case-control study assessing the prevalence of the HOXB13 G84E variant to date and is the first in the UK population. We genotyped 8652 men diagnosed with PrCa within the UK Genetic Prostate Cancer Study (UKGPCS) and 5252 healthy men from the UK ProtecT study. RESULTS: HOXB13 G84E was identified in 0.5% of the healthy controls and 1.5% of the PrCa cases, and it was associated with a 2.93-fold increased risk of PrCa [95% confidence interval (CI) 1.94-4.59; P = 6.27 × 10(-8)]. The risk was even higher among men with family history of PrCa [odds ratio (OR) = 4.53, 95% CI 2.86-7.34; P = 3.1 × 10(-8)] and in young-onset PrCa (diagnosed up to the age of 55 years; OR = 3.11, 95% CI 1.98-5.00; P = 6.1 × 10(-7)). There was no significant association between Gleason Score, presenting prostate specific antigen, tumour-node-metastasis (TNM) stage or NCCN risk group and carrier status. HOXB13 G84E was not associated with overall or cancer-specific survival. We found that the polygenic PrCa risk score (PR score), calculated using the 71 known single-nucleotide polymorphisms (SNPs) associated with PrCa and the HOXB13 G84E variant act multiplicatively on PrCa risk. Based on the estimated prevalence and risk, this rare variant explains ∼1% of the familial risk of PrCa in the UK population. CONCLUSIONS: The clinical importance of HOXB13 G84E in PrCa management has not been established. This variant was found to have no effect on prognostic implications but could be used for stratifying screening, by identifying men at high risk. CLINICAL TRIALS NUMBERS: Prostate Testing for Cancer and Treatment (ProtecT): NCT02044172. UK GENETIC PROSTATE CANCER STUDY: Epidemiology and Molecular Genetics Studies (UKGPCS): NCT01737242.


Assuntos
Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Proteínas de Homeodomínio/genética , Polimorfismo de Nucleotídeo Único/genética , Próstata/metabolismo , Neoplasias da Próstata/genética , Idoso , Estudos de Casos e Controles , Seguimentos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prevalência , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Fatores de Risco , Taxa de Sobrevida , Reino Unido
9.
Br J Cancer ; 110(6): 1663-72, 2014 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-24556621

RESUMO

BACKGROUND: Prostate cancer (PrCa) is one of the most common diseases to affect men worldwide and among the leading causes of cancer-related death. The purpose of this study was to use second-generation sequencing technology to assess the frequency of deleterious mutations in 22 tumour suppressor genes in familial PrCa and estimate the relative risk of PrCa if these genes are mutated. METHODS: Germline DNA samples from 191 men with 3 or more cases of PrCa in their family were sequenced for 22 tumour suppressor genes using Agilent target enrichment and Illumina technology. Analysis for genetic variation was carried out by using a pipeline consisting of BWA, Genome Analysis Toolkit (GATK) and ANNOVAR. Clinical features were correlated with mutation status using standard statistical tests. Modified segregation analysis was used to determine the relative risk of PrCa conferred by the putative loss-of-function (LoF) mutations identified. RESULTS: We discovered 14 putative LoF mutations in 191 samples (7.3%) and these mutations were more frequently associated with nodal involvement, metastasis or T4 tumour stage (P=0.00164). Segregation analysis of probands with European ancestry estimated that LoF mutations in any of the studied genes confer a relative risk of PrCa of 1.94 (95% CI: 1.56-2.42). CONCLUSIONS: These findings show that LoF mutations in DNA repair pathway genes predispose to familial PrCa and advanced disease and therefore warrants further investigation. The clinical utility of these findings will become increasingly important as targeted screening and therapies become more widespread.


Assuntos
Reparo do DNA , Mutação em Linhagem Germinativa , Neoplasias da Próstata/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Risco
10.
Br J Cancer ; 110(4): 1053-7, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24366306

RESUMO

BACKGROUND: Invasive lobular breast cancer (ILC) and lobular carcinoma in situ (LCIS) are characterised by loss of E-cadherin expression. However germline CDH1 mutations are rare in cases of ILC with no family history of hereditary diffuse gastric cancer (HDGC) and have not been described in women with LCIS. METHODS: We screened the CDH1 gene in 50 cases of bilateral LCIS/ILC using Sanger sequencing and MLPA. RESULTS: Sanger sequencing revealed four pathogenic germline mutations, including a novel splicing mutation (c.48+1G>A). The remaining three (c.1465insC, c.1942G>T, c.2398delC) have been previously described. All four cases had bilateral LCIS +/- ILC and no family history of gastric cancer. CONCLUSION: CDH1 germline mutations have not been previously described in women with LCIS. We have shown that germline CDH1 mutations are associated with early onset of bilateral LCIS with or without ILC in women without a family history of gastric cancer. CDH1 mutation screening should be considered in women with early onset of bilateral LCIS/ILC with no family history of HDGC.


Assuntos
Neoplasias da Mama/genética , Caderinas/genética , Carcinoma in Situ/genética , Carcinoma Lobular/genética , Antígenos CD , Sequência de Bases , Neoplasias da Mama/patologia , Carcinoma Lobular/patologia , Feminino , Mutação em Linhagem Germinativa/genética , Humanos , Pessoa de Meia-Idade , Análise de Sequência de DNA
11.
Br J Cancer ; 110(4): 1088-100, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24548884

RESUMO

BACKGROUND: Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying genotyped single-nucleotide polymorphisms (SNPs) and imputed SNPs in FGFR1, FGFR3, FGFR4 and FGFRL1 in the Breast Cancer Association Consortium. METHODS: Data were combined from 49 studies, including 53 835 cases and 50 156 controls, of which 89 050 (46 450 cases and 42 600 controls) were of European ancestry, 12 893 (6269 cases and 6624 controls) of Asian and 2048 (1116 cases and 932 controls) of African ancestry. Associations with risk of breast cancer, overall and by disease sub-type, were assessed using unconditional logistic regression. RESULTS: Little evidence of association with breast cancer risk was observed for SNPs in the FGF receptor genes. The strongest evidence in European women was for rs743682 in FGFR3; the estimated per-allele odds ratio was 1.05 (95% confidence interval=1.02-1.09, P=0.0020), which is substantially lower than that observed for SNPs in FGFR2. CONCLUSION: Our results suggest that common variants in the other FGF receptors are not associated with risk of breast cancer to the degree observed for FGFR2.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Estudos de Casos e Controles , Feminino , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 5 de Fator de Crescimento de Fibroblastos/genética
12.
Br J Cancer ; 106(10): 1697-701, 2012 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-22516946

RESUMO

BACKGROUND: Prostate cancer (PrCa) is one of the most common cancers affecting men but its aetiology is poorly understood. Family history of PrCa, particularly at a young age, is a strong risk factor. There have been previous reports of increased PrCa risk in male BRCA1 mutation carriers in female breast cancer families, but there is a controversy as to whether this risk is substantiated. We sought to evaluate the role of germline BRCA1 mutations in PrCa predisposition by performing a candidate gene study in a large UK population sample set. METHODS: We screened 913 cases aged 36­86 years for germline BRCA1 mutation, with the study enriched for cases with an early age of onset. We analysed the entire coding region of the BRCA1 gene using Sanger sequencing. Multiplex ligation-dependent probe amplification was also used to assess the frequency of large rearrangements in 460 cases. RESULTS: We identified 4 deleterious mutations and 45 unclassified variants (UV). The frequency of deleterious BRCA1 mutation in this study is 0.45%; three of the mutation carriers were affected at age 65 years and one developed PrCa at 69 years. Using previously estimated population carrier frequencies, deleterious BRCA1 mutations confer a relative risk of PrCa of ~3.75-fold, (95% confidence interval 1.02­9.6) translating to a 8.6% cumulative risk by age 65. CONCLUSION: This study shows evidence for an increased risk of PrCa in men who harbour germline mutations in BRCA1. This could have a significant impact on possible screening strategies and targeted treatments.


Assuntos
Genes BRCA1 , Mutação em Linhagem Germinativa , Neoplasias da Próstata/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/etiologia , Risco
13.
Br J Cancer ; 105(8): 1230-4, 2011 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-21952622

RESUMO

BACKGROUND: A family history of prostate cancer (PrCa) is a strong risk factor for the disease, indicating that inherited factors are important in this disease. We previously estimated that about 2% of PrCa cases diagnosed ≤ 55 years harbour a BRCA2 mutation and PrCa among BRCA2 carriers has been shown to be more aggressive, with poorer survival. METHODS: To further evaluate the role of BRCA2 in PrCa predisposition, we screened 1864 men with PrCa aged between 36 and 88 years. We analysed the BRCA2 gene using a novel high-throughput multiplex fluorescence heteroduplex detection system developed for the ABI3130xl genetic analyzer. RESULTS: We identified 19 protein-truncating mutations, 3 in-frame deletions and 69 missense variants of uncertain significance (UV) in our sample set. All the carriers of truncating mutations developed PrCa at ≤ 65 years, with a prevalence of BRCA2 mutation of 1.20% for cases in this age group. CONCLUSION: Based on the estimated frequency of BRCA2 mutations in the United Kingdom we estimate that germline mutations in the BRCA2 gene confer an ∼ 8.6-fold increased risk of PrCa by age 65, corresponding to an absolute risk of ∼ 15% by age 65. These results suggest that routine testing of early onset PrCa cases for germline BRCA2 mutations will further help to refine the prevalence and risk associated with BRCA2 mutations and may be useful for guiding management options.


Assuntos
Idade de Início , Genes BRCA2 , Testes Genéticos , Neoplasias da Próstata/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Análise de Sobrevida
14.
Br J Cancer ; 104(1): 175-7, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21119657

RESUMO

BACKGROUND: The ratio of digit lengths is fixed in utero, and may be a proxy indicator for prenatal testosterone levels. METHODS: We analysed the right-hand pattern and prostate cancer risk in 1524 prostate cancer cases and 3044 population-based controls. RESULTS: Compared with index finger shorter than ring finger (low 2D : 4D), men with index finger longer than ring finger (high 2D : 4D) showed a negative association, suggesting a protective effect with a 33% risk reduction (odds ratio (OR) 0.67, 95% confidence interval (CI) 0.57-0.80). Risk reduction was even greater (87%) in age group <60 (OR 0.13, 95% CI 0.09-0.21). CONCLUSION: Pattern of finger lengths may be a simple marker of prostate cancer risk, with length of 2D greater than 4D suggestive of lower risk.


Assuntos
Dedos/anatomia & histologia , Mãos/fisiologia , Neoplasias da Próstata/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/etiologia , Fatores de Risco
15.
Br J Cancer ; 105(12): 1934-9, 2011 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-22033276

RESUMO

BACKGROUND: Somatic mutations in phosphoinositide-3-kinase catalytic subunit alpha (PIK3CA) are frequent in breast tumours and have been associated with oestrogen receptor (ER) expression, human epidermal growth factor receptor-2 overexpression, lymph node metastasis and poor survival. The goal of this study was to evaluate the association between inherited variation in this oncogene and risk of breast cancer. METHODS: A single-nucleotide polymorphism from the PIK3CA locus that was associated with breast cancer in a study of Caucasian breast cancer cases and controls from the Mayo Clinic (MCBCS) was genotyped in 5436 cases and 5280 controls from the Cancer Genetic Markers of Susceptibility (CGEMS) study and in 30 949 cases and 29 788 controls from the Breast Cancer Association Consortium (BCAC). RESULTS: Rs1607237 was significantly associated with a decreased risk of breast cancer in MCBCS, CGEMS and all studies of white Europeans combined (odds ratio (OR)=0.97, 95% confidence interval (CI) 0.95-0.99, P=4.6 × 10(-3)), but did not reach significance in the BCAC replication study alone (OR=0.98, 95% CI 0.96-1.01, P=0.139). CONCLUSION: Common germline variation in PIK3CA does not have a strong influence on the risk of breast cancer.


Assuntos
Neoplasias da Mama/enzimologia , Predisposição Genética para Doença , Variação Genética , Fosfatidilinositol 3-Quinases/genética , Neoplasias da Mama/genética , Estudos de Casos e Controles , Classe I de Fosfatidilinositol 3-Quinases , Feminino , Humanos
16.
Hum Genet ; 129(6): 687-94, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21465221

RESUMO

Genome-wide association studies (GWAS) have identified more than 30 prostate cancer (PrCa) susceptibility loci. One of these (rs2735839) is located close to a plausible candidate susceptibility gene, KLK3, which encodes prostate-specific antigen (PSA). PSA is widely used as a biomarker for PrCa detection and disease monitoring. To refine the association between PrCa and variants in this region, we used genotyping data from a two-stage GWAS using samples from the UK and Australia, and the Cancer Genetic Markers of Susceptibility (CGEMS) study. Genotypes were imputed for 197 and 312 single nucleotide polymorphisms (SNPs) from HapMap2 and the 1000 Genome Project, respectively. The most significant association with PrCa was with a previously unidentified SNP, rs17632542 (combined P = 3.9 × 10(-22)). This association was confirmed by direct genotyping in three stages of the UK/Australian GWAS, involving 10,405 cases and 10,681 controls (combined P = 1.9 × 10(-34)). rs17632542 is also shown to be associated with PSA levels and it is a non-synonymous coding SNP (Ile179Thr) in KLK3. Using molecular dynamic simulation, we showed evidence that this variant has the potential to introduce alterations in the protein or affect RNA splicing. We propose that rs17632542 may directly influence PrCa risk.


Assuntos
Predisposição Genética para Doença , Calicreínas/genética , Neoplasias da Próstata/genética , RNA Mensageiro/genética , Estudo de Associação Genômica Ampla , Humanos , Masculino , Simulação de Dinâmica Molecular , Polimorfismo de Nucleotídeo Único , Antígeno Prostático Específico/sangue
17.
Hum Reprod ; 26(6): 1318-23, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21421663

RESUMO

BACKGROUND: 'Pregnancies of unknown location' (PULs) include viable and failing intrauterine and extrauterine pregnancies. The aim of this study was to evaluate the role of novel biochemical markers in the prediction of spontaneous resolution of PULs. METHODS: Serum samples were taken at the first visit to the pregnancy unit for measuring the traditional markers ß-hCG and progesterone, and for inhibin A, inhibin pro-αC-related immunoreactivity (inhibin pro-αC-RI) and insulin-like growth factor-binding protein 1 (IGFBP-1). Follow-up was continued until the pregnancy had resolved, the location of the pregnancy and viability was determined or treatment was required. Outcomes were dichotomized into 'spontaneous resolution' and 'other outcome' categories. RESULTS: One-hundred and nine cases of PUL were included in the data analysis. Spontaneous resolution occurred in 70% and a further scan was required in 30% to reach a diagnosis. Levels of progesterone and inhibin A were significantly lower (both P < 0.001) and levels of IGFBP-1 significantly higher (P = 0.02) in the pregnancies that spontaneously resolved than in those pregnancies that required further intervention. In decision tree analysis, the novel markers were less useful than progesterone and ß-hCG in predicting spontaneously resolving PULs. Inhibin pro-αC-RI and IGFBP-1 were not useful in the prediction of spontaneously resolving PULs. Inhibin A is more predictive than ß-hCG alone, but serum progesterone is the best single marker and progesterone and hCG together continues to be the best way of predicting spontaneously resolving PULs. CONCLUSIONS: These novel biochemical markers are not clinically useful in predicting spontaneously resolving PULs.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/sangue , Gravidez Ectópica/sangue , Progesterona/sangue , Biomarcadores/sangue , Árvores de Decisões , Feminino , Humanos , Inibinas/sangue , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Precursores de Proteínas/sangue
18.
Pharmacology ; 88(1-2): 44-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21757974

RESUMO

BACKGROUND/AIMS: Fluoxetine (Prozac) is a selective serotonin reuptake inhibitor currently used to treat depression and mood disorders. It has been widely studied clinically and preclinically, yet there is limited knowledge of its pharmacokinetics in nonhuman primates. METHODS: The present study characterized the pharmacokinetics of fluoxetine and its active metabolite norfluoxetine in rhesus macaques following both acute (1, 3, 5.6 and 10 mg/kg) and chronic doses (5.6 and 10 mg/kg/day) via different routes of administration (intravenous, subcutaneous, intramuscular, and oral). Blood samples were collected at multiple time points following administration and analyzed using mass spectrometry. RESULTS: Fluoxetine had a half-life of 11-16 h and norfluoxetine had a half-life of 21-29 h. Potentially functionally significant serum concentrations of norfluoxetine were present at 24 h even after a single administration of fluoxetine. Similar to observations in humans under steady state conditions, norfluoxetine accounted for the greater percentage of active drug in the blood stream. CONCLUSION: A daily dose of 10 mg/kg administered orally maintained serum concentrations in the human clinical range over the course of 6 weeks. Given the long half-lives of fluoxetine and norfluoxetine observed in this study, precautions should be taken when designing preclinical studies to prevent accumulation of drug serum concentrations.


Assuntos
Antidepressivos/farmacocinética , Fluoxetina/farmacocinética , Inibidores Seletivos de Recaptação de Serotonina/farmacocinética , Administração Oral , Animais , Antidepressivos/administração & dosagem , Antidepressivos/sangue , Antidepressivos/farmacologia , Relação Dose-Resposta a Droga , Vias de Administração de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Feminino , Fluoxetina/administração & dosagem , Fluoxetina/análogos & derivados , Fluoxetina/sangue , Fluoxetina/farmacologia , Humanos , Injeções Subcutâneas , Macaca mulatta , Camundongos , Modelos Animais , Ratos , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Inibidores Seletivos de Recaptação de Serotonina/sangue , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Especificidade da Espécie , Fatores de Tempo
19.
Br J Cancer ; 102(2): 414-8, 2010 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-19997100

RESUMO

BACKGROUND: MSMB, a gene coding for beta-microseminoprotein, has been identified as a candidate susceptibility gene for prostate cancer (PrCa) in two genome-wide association studies (GWAS). SNP rs10993994 is 2 bp upstream of the transcription initiation site of MSMB and was identified as an associated PrCa risk variant. The MSMB protein is underexpressed in PrCa and it was previously proposed to be an independent marker for the recurrence of cancer after radical prostatectomy. METHODS: In this study, the coding region of this gene and 1500 bp upstream of the 5'UTR has been sequenced in germline DNA in 192 PrCa patients with family history. To evaluate the possible effects of these variants we used in silico analysis. RESULTS: No deleterious mutations were identified, however, nine new sequence variants were found, most of these in the promoter and 5'UTR region. In silico analysis suggests that four of these SNPs are likely to have some effect on gene expression either by affecting ubiquitous or prostate-specific transcription factor (TF)-binding sites or modifying splicing efficiency. INTERPRETATION: We conclude that MSMB is unlikely to be a familial PrCa gene and propose that the high-risk alleles of the SNPs in the 5'UTR effect PrCa risk by modifying MSMB gene expression in response to hormones in a tissue-specific manner.


Assuntos
Análise Mutacional de DNA , Neoplasias da Próstata/genética , Proteínas Secretadas pela Próstata/genética , Idoso , Expressão Gênica , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
20.
Breast Cancer Res Treat ; 121(1): 203-10, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19763819

RESUMO

It has been proposed that rare variants within the double strand break repair genes CHEK2, BRIP1 and PALB2 predispose to breast cancer. The aim of this study was to evaluate the prevalence of these variants in an Irish breast cancer cohort and determine their contribution to the development of breast cancer in the west of Ireland. We evaluated the presence of CHEK2_1100delC variant in 903 breast cancer cases and 1,016 controls. Six previously described variants within BRIP1 and five within PALB2 were screened in 192 patients with early-onset or familial breast cancer. Where a variant was evident, it was then examined in the remainder of our 711 unselected breast cancer cases. CHEK2_1100delC was found in 5/903 (0.5%) breast cancer cases compared to 1/1016 (0.1%) controls. One mutation at BRIP1 (2392 C>T) was identified in the early-onset/familial cohort. Examination of this variant in the remainder of our cohort (711 cases) failed to identify any additional cases. None of the previously described PALB2 variants were demonstrated in the early-onset/familial cohort. We show evidence of CHEK2_1100delC and BRIP1 2392 C>T within the Irish population. CHEK2_1100delC and BRIP1 mutations incidence in Ireland is similar to that found in other unselected breast cancer cohorts from northern European countries. We found no evidence to suggest that PALB2 mutation is an important breast cancer predisposition gene in this population.


Assuntos
Neoplasias da Mama/genética , Proteínas de Ligação a DNA/genética , Predisposição Genética para Doença , Proteínas Nucleares/genética , Proteínas Serina-Treonina Quinases/genética , RNA Helicases/genética , Proteínas Supressoras de Tumor/genética , Adulto , Sequência de Bases , Quinase do Ponto de Checagem 2 , Estudos de Coortes , Proteína do Grupo de Complementação N da Anemia de Fanconi , Proteínas de Grupos de Complementação da Anemia de Fanconi , Feminino , Genótipo , Humanos , Irlanda , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
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