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1.
Lett Appl Microbiol ; 61(2): 130-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25900660

RESUMO

UNLABELLED: Faecal indicator bacteria (FIB) and harmful algal blooms (HABs) threaten the health and the economy of coastal communities worldwide. Emerging automated sampling technologies combined with molecular analytical techniques could enable rapid detection of micro-organisms in-situ, thereby improving resource management and public health decision-making. We evaluated this concept using a robotic device, the Environmental Sample Processor (ESP). The ESP automates in-situ sample collection, nucleic acid extraction and molecular analyses. Here, the ESP measured and reported concentrations of FIB (Enterococcus spp.), a microbial source-tracking marker (human-specific Bacteriodales) and a HAB species (Psuedo-nitzschia spp.) over a 45-day deployment on the Santa Cruz Municipal Wharf (Santa Cruz, CA, USA). Both FIB and HABs were enumerated from single in-situ collected water samples. The in-situ qPCR efficiencies ranged from 86% to 105%, while the limit of quantifications during the deployment was 10 copies reaction(-1) . No differences were observed in the concentrations of enterococci, the human-specific marker in Bacteroidales spp., and P. australis between in-situ collected sample and traditional hand sampling methods (P > 0·05). Analytical results were Internet-accessible within hours of sample collection, demonstrating the feasibility of same-day public notification of current water quality conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: This study presents the first report of in-situ qPCR enumeration of both faecal indicators and harmful algal species in coastal marine waters. We utilize a robotic device for in-situ quantification of enterococci, the human-specific marker in Bacteriodales and Pseudo-nitzschia spp. from the same water samples collected and processed in-situ. The results demonstrate that rapid, in-situ monitoring can be utilized to identify and quantify multiple health-relevant micro-organisms important in water quality monitoring and that this monitoring can be used to inform same-day notifications.


Assuntos
Enterococcus/isolamento & purificação , Monitoramento Ambiental/métodos , Fezes/microbiologia , Proliferação Nociva de Algas , Reação em Cadeia da Polimerase em Tempo Real/métodos , Enterococcus/genética , Humanos , Robótica , Qualidade da Água
2.
Br J Dermatol ; 169(4): 880-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23746131

RESUMO

BACKGROUND: Melanoma incidence often shows an increasing latitudinal gradient from north to south among white European populations. OBJECTIVES: To assess emerging regional melanoma incidence patterns in England. METHODS: All primary invasive cutaneous melanomas diagnosed in England in people aged 10-89 years, in 1996-2006, were ascertained. Age-standardized incidence rates by sex, age and Government Office Region were calculated for the entire population and for the white population only. Rates according to socioeconomic deprivation were further calculated among those aged under 30 years. Regional heterogeneity and latitude and deprivation trends were assessed by Poisson regression and tests for trend. RESULTS: Overall, melanoma incidence in England was highest in the South West (overall, 18·75; white, 19·03 per 100,000) and lowest in London (overall, 8·85; white, 11·22 per 100,000). Incidence significantly increased with more southerly latitudes in all white adults aged over 30 years (P < 0·0001), except women aged 30-49 years (1·8%, P = 0·10). However, these north-south latitude trends were reversed in white 10-29 year olds, with sex-specific analyses showing an absence of trend in male subjects (2·7%, P = 0·41) and a strong decreasing trend (-9·8%, P < 0·0001) in female subjects. The highest rates in the young female population occurred in the North West (5·46 per 100,000), and specifically in the second most deprived (5·69 per 100,000) and the second most affluent (6·48 per 100,000) groups. CONCLUSIONS: Melanoma incidence is high in young people in northern England, including among the moderately deprived, reversing the expected north-south incidence gradients. Prevalent sunbed use in northern England and holiday sun exposure abroad may explain these emerging trends.


Assuntos
Melanoma/epidemiologia , Neoplasias Cutâneas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Inglaterra/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Características de Residência/estatística & dados numéricos , Fatores Socioeconômicos , Banho de Sol , Viagem , Adulto Jovem
3.
Br J Dermatol ; 165(4): 859-64, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21623751

RESUMO

BACKGROUND: National melanoma incidence trends with details of anatomical site have not been previously described for England. OBJECTIVES: To describe site-specific trends in cutaneous melanoma for England as a whole during the last three decades. METHODS: Anonymized data, 1979-2006, were obtained from national cancer registrations of all patients in England up to age 89years with incident primary invasive cutaneous melanomas (n=124055). Sex-specific age-standardized incidence rates and average annual percentage change in rates were calculated for each broad anatomical site. RESULTS: Overall incidence rates of cutaneous melanoma in England, 1979-2006, were 81 and 100 per million, in males and females, respectively. Site-specific rates were consistently highest on the lower limbs in females followed by the trunk in males. Greatest annual increases occurred on the trunk in both sexes over 45years (males 9·9%, females 6·8%), then upper limbs (males 8·7%, females 6·8%). Incidence trends in males relative to females varied little across sites apart from a more rapid rise in head/neck melanomas in males than in females after the 1980s. CONCLUSIONS: Invasive melanoma rates continue to rise in England, particularly on the trunk and arms, and in males on the head/neck. The steeper increases in melanoma rates among males are consistent with their greater sun exposure and poorer compliance with sun protection measures than females.


Assuntos
Melanoma/epidemiologia , Neoplasias Cutâneas/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Braço , Criança , Pré-Escolar , Inglaterra/epidemiologia , Feminino , Neoplasias de Cabeça e Pescoço/epidemiologia , Humanos , Incidência , Lactente , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Distribuição por Sexo , Tronco , Adulto Jovem
4.
Br J Cancer ; 101(11): 1939-45, 2009 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19888224

RESUMO

BACKGROUND: Between 1979 and 2001, an analysis of cancer survival in young people in England, aged 13 to 24 years, showed overall improvements. However, for some diagnostic groups, little or no increases were observed. The aim of this study was to analyse the regional distribution of cancer survival in teenagers and young adults in England in order to identify patterns and potential for improvements at a regional scale. METHODS: We examined geographical and temporal patterns in relative survival in cancer patients aged 13-24 years in England during the time period 1979-2001. Cancer cases were grouped according to an internationally recognised morphology-based diagnostic scheme. RESULTS: For most diagnostic groups, there was little variation in survival between regions, except for testicular germ cell tumours (P=0.006) and colorectal carcinoma (P=0.002). For certain diagnostic groups, the temporal pattern in survival differed between regions. However, in regions that showed poor survival during the early part of the study period, greatest improvements were observed in groups such as acute lymphoid leukaemia, acute myeloid leukaemia, testicular tumours and melanoma. CONCLUSION: In conclusion, there was a reduction in the differences in survival between regions during the study period.


Assuntos
Neoplasias/mortalidade , Adolescente , Adulto , Inglaterra/epidemiologia , Humanos , Dinâmica Populacional , Taxa de Sobrevida , Adulto Jovem
5.
Br J Cancer ; 100(1): 188-93, 2009 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-19127271

RESUMO

There is a paucity of population-based studies examining incidence and survival trends in childhood bone tumours. We used high quality data from four population-based registries in England. Incidence patterns and trends were described using Poisson regression. Survival trends were analysed using Cox regression. There were 374 cases of childhood (ages 0-14 years) bone tumours (206 osteosarcomas, 144 Ewing sarcomas, 16 chondrosarcomas, 8 other bone tumours) registered in the period 1981-2002. Overall incidence (per million person years) rates were 2.63 (95% confidence interval (CI) 2.27-2.99) for osteosarcoma, 1.90 (1.58-2.21) for Ewing sarcoma and 0.21 (0.11-0.31) for chondrosarcoma. Incidence of Ewing sarcoma declined at an average rate of 3.1% (95% CI 0.6-5.6) per annum (P=0.04), which may be due to tumour reclassification, but there was no change in osteosarcoma incidence. Survival showed marked improvement over the 20 years (1981-2000) for Ewing sarcoma (hazard ratio (HR) per annum=0.95 95% CI 0.91-0.99; P=0.02). However, no improvement was seen for osteosarcoma patients (HR per annum=1.02 95% CI 0.98-1.05; P=0.35) over this time period. Reasons for failure to improve survival including potential delays in diagnosis, accrual to trials, adherence to therapy and lack of improvement in treatment strategies all need to be considered.


Assuntos
Neoplasias Ósseas/epidemiologia , Adolescente , Neoplasias Ósseas/mortalidade , Criança , Pré-Escolar , Inglaterra/epidemiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Osteossarcoma/epidemiologia , Modelos de Riscos Proporcionais , Sarcoma de Ewing/epidemiologia , Taxa de Sobrevida
6.
Cancer Causes Control ; 20(2): 129-36, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18766446

RESUMO

Little is known regarding the aetiology of central nervous system tumors in children. Recent studies have speculated on a potential infectious aetiology, but no clear associations have been found. This article uses parent reported questionnaire data from the UK Childhood Cancer Study (UKCCS), a population-based case-control study, to examine the relationship between the infectious exposure in the first year of life and the likelihood of developing a CNS tumor. The variables representing infectious exposure were social contact (including social contact with other infants and attendance at informal and formal day care), sharing a bedroom with another child, birth order, and exposure to a school-age child within the home. Children reported to have had no social contact with other infants in the first year of life displayed an increased risk of developing a CNS tumor when compared to those who had (OR 1.37, 95% CI 1.08-1.75). This effect was most prominent in the primitive neuroectodermal tumor/medulloblastoma subgroup (OR 1.78, 95% CI 1.12-2.83). Those who had attended informal (OR 0.86, 95% CI 0.68-1.09) or formal day care (OR 0.93, 95% CI 0.68-1.26) showed slightly non-statistically significant reduced risks when compared to those reporting social contact only. No association with any of the other variables was observed. Overall, the inconsistent findings by variable and tumor subtype suggest that an early exposure to infections is not strongly implicated in the aetiology of CNS tumors. However, the effect for social contact outside the home, particularly for PNET/medulloblastomas warrants further investigation.


Assuntos
Neoplasias do Sistema Nervoso Central/epidemiologia , Neoplasias do Sistema Nervoso Central/microbiologia , Hospital Dia , Exposição Ambiental , Família , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Fatores de Risco
7.
Science ; 286(5449): 2528-31, 1999 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-10617473

RESUMO

The hCHK2 gene encodes the human homolog of the yeast Cds1 and Rad53 G2 checkpoint kinases, whose activation in response to DNA damage prevents cellular entry into mitosis. Here, it is shown that heterozygous germ line mutations in hCHK2 occur in Li-Fraumeni syndrome, a highly penetrant familial cancer phenotype usually associated with inherited mutations in the TP53 gene. These observations suggest that hCHK2 is a tumor suppressor gene conferring predisposition to sarcoma, breast cancer, and brain tumors, and they also provide a link between the central role of p53 inactivation in human cancer and the well-defined G2 checkpoint in yeast.


Assuntos
Fase G2 , Genes Supressores de Tumor , Mutação em Linhagem Germinativa , Síndrome de Li-Fraumeni/genética , Proteínas Serina-Treonina Quinases/genética , Alelos , Apoptose , Neoplasias Encefálicas/genética , Neoplasias da Mama/genética , Quinase 1 do Ponto de Checagem , Quinase do Ponto de Checagem 2 , Feminino , Fase G1 , Genes p53 , Predisposição Genética para Doença , Heterozigoto , Humanos , Síndrome de Li-Fraumeni/enzimologia , Síndrome de Li-Fraumeni/patologia , Masculino , Linhagem , Polimorfismo Genético , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Sarcoma/genética , Transdução de Sinais , Células Tumorais Cultivadas
8.
J Med Genet ; 45(2): 106-13, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18245390

RESUMO

BACKGROUND: A variety of abnormalities have been demonstrated at chromosome 11p15 in individuals with overgrowth and growth retardation. The identification of these abnormalities is clinically important but often technically difficult. Methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) is a simple but effective technique able to identify and differentiate methylation and copy number abnormalities, and thus is potentially well suited to the analysis of 11p15. AIMS: To customize and test an MS-MLPA assay capable of detecting and distinguishing the full spectrum of known 11p15 epigenetic and copy number abnormalities associated with overgrowth and growth retardation and to assess its effectiveness as a first line investigation of these abnormalities. METHODS: Five synthetic probe pairs were designed to extend the range of abnormalities detectable with a commercially available MS-MLPA assay. To define the normal values, 75 normal control samples were analysed using the customized assay. The assay was then used to analyse a "test set" of 24 normal and 27 abnormal samples, with data analysed by two independent blinded observers. The status of all abnormal samples was confirmed by a second technique. RESULTS: The MS-MLPA assay gave reproducible, accurate methylation and copy number results in the 126 samples assayed. The blinded observers correctly identified and classified all 51 samples in the test set. CONCLUSIONS: MS-MLPA robustly and sensitively detects and distinguishes epigenetic and copy number abnormalities at 11p15 and is an effective first line investigation of 11p15 in individuals with overgrowth or growth retardation.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 11/genética , Transtornos do Crescimento/genética , Síndrome de Beckwith-Wiedemann/genética , Metilação de DNA , Epigênese Genética , Feminino , Dosagem de Genes , Impressão Genômica , Humanos , Masculino , Repetições de Microssatélites , Técnicas de Sonda Molecular , Técnicas de Amplificação de Ácido Nucleico
9.
Br J Cancer ; 99(5): 830-5, 2008 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-18728673

RESUMO

Cancer is the leading cause of disease-related death in teenagers and young adults aged 13-24 years (TYAs) in England. We have analysed national 5-year relative survival among more than 30,000 incident cancer cases in TYAs. For cancer overall, 5-year survival improved from 63% in 1979-84 to 74% during 1996-2001 (P<0.001). However, there were no sustained improvements in survival over time among high-grade brain tumours and bone and soft tissue sarcomas. Survival patterns varied by age group (13-16, 17-20, 21-24 years), sex and diagnosis. Survival from leukaemia and brain tumours was better in the youngest age group but in the oldest from germ-cell tumours (GCTs). For lymphomas, bone and soft tissue sarcomas, melanoma and carcinomas, survival was not significantly associated with age. Females had a better survival than males except for GCTs. Most groups showed no association between survival and socioeconomic deprivation, but for leukaemias, head and neck carcinoma and colorectal carcinoma, survival was significantly poorer with increasing deprivation. These results will aid the development of national specialised service provision for this age group and identify areas of clinical need that present the greatest challenges.


Assuntos
Neoplasias/patologia , Análise de Sobrevida , Adolescente , Adulto , Inglaterra , Humanos , Neoplasias/classificação , Fatores Socioeconômicos
10.
Eur J Cancer ; 44(1): 92-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18042376

RESUMO

Risk factors for central nervous system (CNS) tumours in children remain largely unknown. Evidence of an inverse relationship between atopy and tumour development exists in adults but little is known about childhood tumours. This study aims to examine the risk of childhood CNS tumours given a history of eczema and asthma. Cases of children diagnosed with CNS tumours (n=575) and controls (n=6292) from the UK Childhood Cancer Study (UKCCS) were analysed using conditional logistic regression comparing reported histories of allergic disease. Asthma was statistically significantly and negatively associated with all CNS tumours (odds ratios, OR 0.75, confidence of interval, CI(95%): 0.58-0.97), though this was not observed for eczema (OR 0.94, CI(95%): 0.74-1.18). Individuals who had suffered both asthma and eczema showed the most significant reduction in risk (OR 0.48, CI(95%): 0.28-0.81). Analysis by tumour subtype showed the strongest effect for the medulloblastoma/PNET group. These results may have a biological explanation with raised immunosurveillance in atopic individuals protecting against the development of brain tumours. Alternative explanations might include bias, reverse causality or confounding.


Assuntos
Asma/complicações , Neoplasias do Sistema Nervoso Central/etiologia , Eczema/complicações , Adolescente , Fatores Etários , Idade de Início , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Sons Respiratórios , Fatores de Risco , Inquéritos e Questionários
11.
J Med Genet ; 43(4): 289-94, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16155191

RESUMO

In recent years the use of radiation treatment for benign tumours has increased with the advent of stereotactic delivery and, in particular, single high dose gamma knife therapy. This has been particularly true for benign CNS (central nervous system) tumours such as vestibular schwannoma, meningioma, pituitary adenoma, and haemangioblastoma. While short term follow up in patients with isolated tumours suggests this treatment is safe, there are particular concerns regarding its use in childhood and in tumour predisposing syndromes. We have reviewed the use of radiation treatment in these contexts with particular regard to malignant transformation and new tumour induction. This review indicates that much more caution is warranted regarding the use of radiation treatment for benign tumours in childhood and in tumour prone conditions such as the neurofibromatoses.


Assuntos
Transformação Celular Neoplásica , Neoplasias Induzidas por Radiação/epidemiologia , Neoplasias/radioterapia , Síndrome do Nevo Basocelular/radioterapia , Humanos , Síndrome de Li-Fraumeni/radioterapia , Neoplasias/etiologia , Neurofibromatoses/radioterapia , Radioterapia/efeitos adversos , Retinoblastoma/radioterapia , Fatores de Risco , Síndrome , Doença de von Hippel-Lindau/radioterapia
12.
Cancer Res ; 54(5): 1298-304, 1994 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8118819

RESUMO

The entire coding sequence of the p53 gene was analysed for the presence of mutations in 12 families conforming to a restricted definition of Li-Fraumeni syndrome (classic LFS) and nine families with features of LFS conforming to a broader definition. Mutations were detected in seven families. Six were point mutations with one each affecting codons 175, 180, and 220 and three affecting codon 248. The seventh was a deletion/insertion mutation in exon 4. Germline mutations in p53 were a feature of families which included children with rhabdomyosarcoma and/or adrenal cortical carcinoma. Germline p53 mutations were detected in six of the nine families with such tumors. An analysis of these 7 mutations, together with 34 published examples, showed that more than one-half were transitions at CpG dinucleotides, suggesting that the majority of germline p53 mutations may arise as a result of spontaneous events. The most common cancers occurring in the 41 families with germline p53 mutations, in common with classic LFS, were bone and soft tissue sarcoma, breast cancer, brain tumors, leukemia, and adrenocortical carcinoma, although less than one-half of the probands with germline p53 mutations came from classic LFS families. More than one-half of the cancers overall and nearly one-third of the breast cancers were diagnosed before 30 years of age. These observations have important implications for asymptomatic carriers of germline p53 mutations, and there is a need for international collaboration in the development of protocols for the management of such families.


Assuntos
Genes p53/genética , Síndrome de Li-Fraumeni/genética , Mutação/genética , Sequência de Bases , Criança , Códon/genética , Éxons/genética , Saúde da Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem , Prevalência
13.
Cancer Res ; 57(15): 3245-52, 1997 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9242456

RESUMO

We have previously reported on the analysis of TP53 coding mutations in 12 classic Li-Fraumeni syndrome (LFS) families plus 9 families that were Li-Fraumeni-like (LFL) families (J. M. Birch et al., Cancer Res., 54: 1298-1304, 1994). Mutations were found in 6 of 12 LFS families and in 1 of 9 LFL families. We have now extended these studies to include an additional nine LFS and nine LFL families, and TP53 mutations have been detected in eight of nine LFS families and in three of nine LFL families. Six of the new mutations described here are the same as those previously identified in other Li-Fraumeni families and are missense mutations at codons 245, 248, and 273 (in two families); a nonsense mutation at codon 209; and a mutation at the splice donor site in exon 4. The other five mutations are novel germ-line mutations and include missense mutations at codons 136 and 344, a 2-bp deletion within codon 191, a splice acceptor mutation in intron 3, and a 167-bp deletion of part of exon 1 and intron 1. In addition, we have detected a codon 175 mutation in a family previously reported as TP53 negative. To summarize all of the data from the families we have studied in this and our previous report (J. M. Birch et al., Cancer Res., 54: 1298-1304, 1994), mutations have been detected in 15 of 21 LFS families (71%) and in 4 of 18 LFL families (22%). These figures are somewhat higher than those previously reported by us and others for the frequency of TP53 mutations in LFS and LFL families. This could reflect our analysis of all 11 exons of TP53, including noncoding regions, as well as the use of direct sequencing rather than other less-sensitive mutation detection methods.


Assuntos
Genes p53/genética , Mutação em Linhagem Germinativa/genética , Síndrome de Li-Fraumeni/genética , Feminino , Ligação Genética , Humanos , Masculino , Mutação , Regiões Promotoras Genéticas/genética
14.
Oncogene ; 9(9): 2737-8, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8058339

RESUMO

CHOP (GADD153) has been shown to be a dominant negative inhibitor of specific transcription factors. Direct sequencing of the gene, amplified from the DNA of a Li-Fraumeni family index case (liposarcoma, breast cancer) revealed a constitutional variant within the coding region. This alteration, though not responsible for the Li-Fraumeni phenotype, resulted in a glutamic acid to lysine switch within the leucine zipper domain, at a residue conserved between CHOP and its potential target molecules and between the human and hamster sequences. The variant created a Taq I restriction fragment length polymorphism (RFLP) facilitating screening. Analysis of 159 breast tumour DNA samples detected two encoding variant alleles (tumour and constitutional DNA).


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT , Proteínas de Ligação a DNA/genética , Zíper de Leucina , Proteínas Nucleares/genética , Fatores de Transcrição/antagonistas & inibidores , Adulto , Sequência de Bases , Neoplasias da Mama/genética , Proteínas de Ligação a DNA/química , Feminino , Humanos , Dados de Sequência Molecular , Neoplasias/etiologia , Neoplasias/genética , Proteínas Nucleares/química , Fator de Transcrição CHOP
15.
Oncogene ; 14(3): 277-82, 1997 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-9018113

RESUMO

Cancer predisposition in approximately 60% of Li-Fraumeni Syndrome (LFS) families is associated with germline mutation of the TP53 gene. The p53 protein has been shown to mediate G1 arrest following DNA damage. We have investigated gamma-irradiation-induced transient and permanent G1 arrest in normal and LFS fibroblasts. The duration of transient G1 arrest varied between strains, but there was no difference in the range between normal (2-12 h) and LFS (1-13 h) cells. However, the extent of permanent G1 arrest was greatly reduced in LFS fibroblasts (mean 33+/-8% of the cell population) compared with normals (mean 67+/-9%) and correlated with their increased radiation survival (r=0.97, P<0.001). This phenotype was observed in LFS fibroblasts both with (seven cases) and without (two cases) TP53 mutation. Parallel studies with fibroblasts derived from cancer-prone, p53-deficient mice revealed no radiation-induced G1 cell cycle arrest in p53 null (-/-) cells. The p53 +/- cells were comparable to the wt p53 cells in transient G1 arrest capacity, but showed a diminished permanent G1 arrest. These data clearly implicate p53 function in permanent G1 arrest. The reduced capacity for DNA damage-induced, permanent G1 arrest in LFS may contribute significantly to cancer predisposition in this familial syndrome.


Assuntos
Fase G1/efeitos da radiação , Genes p53/genética , Síndrome de Li-Fraumeni/genética , Animais , DNA de Neoplasias/biossíntese , Suscetibilidade a Doenças , Fibroblastos/efeitos da radiação , Fase G1/genética , Humanos , Síndrome de Li-Fraumeni/patologia , Camundongos , Camundongos Knockout , Mutação , Ensaio Tumoral de Célula-Tronco
16.
Oncogene ; 12(11): 2437-42, 1996 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-8649785

RESUMO

We report details of a family with classic Li-Fraumeni syndrome in which there is a mutation in codon 344 of the tumour suppressor gene TP53. Codon 344 is a key residue within the tetramerisation domain, and the amino acid substitution of a proline for a leucine is predicted to have profound implications for tetramerisation and potentially DNA binding. This is the first report of a mutation at this residue in either sporadic tumours or in the germline and the first report of a germline mutation within the tetramerisation domain. The family does not appear to be remarkable in the spectrum of tumours, and there is loss of the wild-type allele in a leiomyosarcoma from the proband. A cell line has been established from the tumour of the proband and cytogenetic and molecular studies carried out, providing an extensive analysis in this family.


Assuntos
Códon/genética , Genes p53/genética , Síndrome de Li-Fraumeni/genética , Mutação Puntual/genética , Adulto , Alelos , Sequência de Bases , Feminino , Genótipo , Humanos , Cariotipagem , Masculino , Dados de Sequência Molecular , Linhagem , Análise de Sequência de DNA
17.
Oncogene ; 20(21): 2647-54, 2001 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-11420676

RESUMO

Germline TP53 splicing mutations have been described infrequently (>2%) in the literature, however in a series of 40 patients and families identified by our group in which there are germline TP53 mutations, seven affect splicing (18%). The low figure reported in the literature might reflect the method of mutation detection, which in many studies does not include all splice junctions. These data indicate that a significant proportion of TP53 germline mutations are currently unrecognized. We have carried out detailed studies of the effects of the different mutations on splicing, and see distinct variations in the effects of the same mutation in different patients. Furthermore we have identified the usage of a non-consensus splice donor site in four families with an intron 4 splice donor mutation.


Assuntos
Processamento Alternativo/fisiologia , Genes p53/genética , Mutação em Linhagem Germinativa/fisiologia , Processamento Alternativo/genética , Linhagem Celular , Fibroblastos/fisiologia , Mutação em Linhagem Germinativa/genética , Humanos , Imuno-Histoquímica , Íntrons , Síndrome de Li-Fraumeni/genética , Perda de Heterozigosidade , Linfócitos/fisiologia , Neoplasias/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/fisiologia
18.
Oncogene ; 14(7): 865-71, 1997 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-9047394

RESUMO

We have studied a total of 36 tumours from 28 patients with germline mutations to the TP53 gene for loss of heterozygosity at TP53 using techniques of both direct sequencing and restriction fragment length polymorphism analysis. All patients were from families conforming to the definition of classical Li-Fraumeni syndrome (LFS) or were Li-Fraumeni-like (LFL). The data we have obtained show that loss of the wild-type TP53 gene is observed in under half (44%) of all tumours, and that the pattern of LOH at TP53 may be mutation specific. LOH has been observed in premalignant as well as invasive tumours. Two tumours (6%) show loss of the mutant allele and retention of the wild-type. To confirm that TP53 is indeed the target for LOH events on chromosome 17, we have used additional microsatellite repeats to examine patterns of allelic imbalance along the length of chromosome 17. Data from this analysis indicate that TP53 is the target of loss, but reveal some other interesting patterns of allelic imbalance at other loci on chromosome 17.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 17 , Genes p53 , Síndrome de Li-Fraumeni/genética , Mutação , Neoplasias/genética , Humanos
19.
Oncogene ; 17(9): 1061-8, 1998 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-9764816

RESUMO

The Li-Fraumeni cancer predisposition syndrome is associated with germline TP53 mutations in the majority of families. We have investigated cancer incidence in 34 Li-Fraumeni families, according to their constitutional TP53 mutation status. Families with germline missense mutations in the core DNA binding domain showed a more highly penetrant cancer phenotype than families with other TP53 mutations or no mutation. Cancer phenotype in families carrying such mutations was characterized by a higher cancer incidence and earlier ages at diagnosis, especially of breast cancer and brain tumours, compared with families carrying protein truncating or other inactivating mutations (P=0.03 for all cancers, P=0.006 for breast cancers, P=0.05 for brain tumours). Proband cancers showed significantly younger ages at diagnosis in those with missense mutations in the DNA binding domain than in those with protein inactivating mutations (P=0.031). In individuals with the former type of mutation, there was a significantly lower proportion of tumours which showed loss of the wild-type TP53 allele (P=0.004). These results are consistent with observations in experimental systems which demonstrate that certain mutations exhibit gain of function and/or dominant-negative properties. Our results support an enhanced oncogenic potential for such mutations in human populations.


Assuntos
Família , Síndrome de Li-Fraumeni/genética , Neoplasias/genética , Proteína Supressora de Tumor p53/genética , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Estudos de Coortes , Análise Mutacional de DNA , Saúde da Família , Feminino , Genótipo , Mutação em Linhagem Germinativa/genética , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo
20.
Oncogene ; 20(34): 4621-8, 2001 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-11498785

RESUMO

The spectrum and frequency of cancers associated with germline TP53 mutations are uncertain. To address this issue a cohort of individuals from 28 families with Li-Fraumeni syndrome, segregating germline TP53 mutations was established. Predicted cancers were estimated by applying age, morphology, site and sex-specific UK cancer statistics to person-years at risk. Observed and predicted cancers were compared and two-sided P-values calculated. Cancer types occurring to excess and showing P-values <0.02, were designated strongly associated with germline TP53 mutations. These were removed from the data and a second round of analyses performed. Cancer types with P-values <0.02 and 0.02-0.05 in the second round analyses were considered moderately and weakly associated respectively. Strongly associated cancers were: breast carcinoma, soft tissue sarcomas, osteosarcoma, brain tumours, adrenocortical carcinoma, Wilms' tumour and phyllodes tumour. Carcinoma of pancreas was moderately associated. Leukaemia and neuroblastoma were weakly associated. Other common carcinomas including lung, colon, bladder, prostate, cervix and ovary did not occur to excess. Although breast carcinoma and sarcomas were numerically most frequent, the greatest increases relative to general population rates were in adrenocortical carcinoma and phyllodes tumour. We conclude that germline TP53 mutations do not simply increase general cancer risk. There are tissue-specific effects.


Assuntos
Mutação em Linhagem Germinativa , Síndrome de Li-Fraumeni/epidemiologia , Síndrome de Li-Fraumeni/genética , Proteína Supressora de Tumor p53/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Saúde da Família , Feminino , Predisposição Genética para Doença , Heterozigoto , Humanos , Lactente , Síndrome de Li-Fraumeni/patologia , Masculino , Pessoa de Meia-Idade
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