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1.
Hum Mol Genet ; 31(16): 2728-2737, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35323939

RESUMO

Around 95% of patients with clinical features that meet the diagnostic criteria for von Hippel-Lindau disease (VHL) have a detectable inactivating germline variant in VHL. The VHL protein (pVHL) functions as part of the E3 ubiquitin ligase complex comprising pVHL, elongin C, elongin B, cullin 2 and ring box 1 (VCB-CR complex), which plays a key role in oxygen sensing and degradation of hypoxia-inducible factors. To date, only variants in VHL have been shown to cause VHL disease. We undertook trio analysis by whole-exome sequencing in a proband with VHL disease but without a detectable VHL mutation. Molecular studies were also performed on paired DNA extracted from the proband's kidney tumour and blood and bioinformatics analysis of sporadic renal cell carcinoma (RCC) dataset was undertaken. A de novo pathogenic variant in ELOC NM_005648.4(ELOC):c.236A>G (p.Tyr79Cys) gene was identified in the proband. ELOC encodes elongin C, a key component [C] of the VCB-CR complex. The p.Tyr79Cys substitution is a mutational hotspot in sporadic VHL-competent RCC and has previously been shown to mimic the effects of pVHL deficiency on hypoxic signalling. Analysis of an RCC from the proband showed similar findings to that in somatically ELOC-mutated RCC (expression of hypoxia-responsive proteins, no somatic VHL variants and chromosome 8 loss). These findings are consistent with pathogenic ELOC variants being a novel cause for VHL disease and suggest that genetic testing for ELOC variants should be performed in individuals with suspected VHL disease with no detectable VHL variant.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Doença de von Hippel-Lindau , Carcinoma de Células Renais/genética , Elonguina/genética , Humanos , Hipóxia , Neoplasias Renais/genética , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Doença de von Hippel-Lindau/genética
2.
Matern Child Nutr ; : e13677, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961562

RESUMO

Poor measurement quality has set back the utility of anthropometry in defining childhood malnutrition, prompting calls for alternative measurement techniques. This study aimed to assess the reliability of anthropometric measurements using a digital height board in comparison to an analog height board in Namibian children under 5 years of age. A cross-sectional, descriptive study was conducted (n = 425) between the age of 6 and 59 months, using anthropometric measurements of weight, height and mid-upper arm circumference. Two trained enumerators each collected four height measurements of each child: two using an analog height board and two using a digi-board. The repeated height measurements between and within the enumerators were used to determine intra- and interobserver reliability. Reliability of the digi-board was assessed using the technical error of measurement (TEM), relative TEM (%TEM), intraclass correlation and a Bland-Altman analysis to assess the agreement between the two methods. In all these assessments, the analog height board was considered as the gold standard and used for comparison. The digi-board showed superiority to the analog height board in terms of reliability (analog TEM = 0.22, digi-board TEM = 0.16). Although the digi-board has potential to improve child anthropometry, further clinical and large survey studies are needed to validate the used of this tool in routine population-based surveys.

3.
Int J Cancer ; 148(2): 307-319, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-32851660

RESUMO

Blood lipids have been associated with the development of a range of cancers, including breast, lung and colorectal cancer. For endometrial cancer, observational studies have reported inconsistent associations between blood lipids and cancer risk. To reduce biases from unmeasured confounding, we performed a bidirectional, two-sample Mendelian randomization analysis to investigate the relationship between levels of three blood lipids (low-density lipoprotein [LDL] and high-density lipoprotein [HDL] cholesterol, and triglycerides) and endometrial cancer risk. Genetic variants associated with each of these blood lipid levels (P < 5 × 10-8 ) were identified as instrumental variables, and assessed using genome-wide association study data from the Endometrial Cancer Association Consortium (12 906 cases and 108 979 controls) and the Global Lipids Genetic Consortium (n = 188 578). Mendelian randomization analyses found genetically raised LDL cholesterol levels to be associated with lower risks of endometrial cancer of all histologies combined, and of endometrioid and non-endometrioid subtypes. Conversely, higher genetically predicted HDL cholesterol levels were associated with increased risk of non-endometrioid endometrial cancer. After accounting for the potential confounding role of obesity (as measured by genetic variants associated with body mass index), the association between genetically predicted increased LDL cholesterol levels and lower endometrial cancer risk remained significant, especially for non-endometrioid endometrial cancer. There was no evidence to support a role for triglycerides in endometrial cancer development. Our study supports a role for LDL and HDL cholesterol in the development of non-endometrioid endometrial cancer. Further studies are required to understand the mechanisms underlying these findings.


Assuntos
HDL-Colesterol/sangue , LDL-Colesterol/sangue , Neoplasias do Endométrio/sangue , Triglicerídeos/sangue , Estudos de Casos e Controles , HDL-Colesterol/genética , LDL-Colesterol/genética , Neoplasias do Endométrio/genética , Feminino , Estudo de Associação Genômica Ampla , Humanos , Análise da Randomização Mendeliana , Risco , Triglicerídeos/genética
4.
Int J Audiol ; 59(5): 374-382, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32011194

RESUMO

Objective: The objective of this study was to provide proof-of-concept of a single session of tinnitus instruction and counselling with and without homework.Design: A mixed-method design using questionnaires and thematic evaluation of qualitative data was implemented.Study sample: Sixteen participants received instruction in a single, one-to-one counselling session; eight participants additionally undertook homework consisting of either positive visualisation augmented by sound or a workbook of written and drawing activities supporting the instruction provided in the counselling session. All participants completed questionnaires just before and 3 weeks after the intervention, half were interviewed 3 weeks following the intervention.Results: Average tinnitus functional index (TFI) scores were 45 (SD 25) before and 29 (SD 23) following counselling, with a change of 4.8 or greater recorded in 75% and change of 13 points or greater in 50% of participants. Both counselling and counselling with homework showed similar changes in the TFI. This finding was supported by the qualitative analysis from which a model consisting of the themes of counselling benefit, content, application and homework benefit was derived.Conclusions: This study provides proof-of-concept of a single tinnitus instruction and counselling session, based on an ecological model of tinnitus.


Assuntos
Aconselhamento/métodos , Educação de Pacientes como Assunto/métodos , Zumbido/reabilitação , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Índice de Gravidade de Doença , Inquéritos e Questionários , Ensino , Resultado do Tratamento
5.
J Med Genet ; 55(6): 384-394, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29386252

RESUMO

BACKGROUND: Germline pathogenic variants in SDHB/SDHC/SDHD are the most frequent causes of inherited phaeochromocytomas/paragangliomas. Insufficient information regarding penetrance and phenotypic variability hinders optimum management of mutation carriers. We estimate penetrance for symptomatic tumours and elucidate genotype-phenotype correlations in a large cohort of SDHB/SDHC/SDHD mutation carriers. METHODS: A retrospective survey of 1832 individuals referred for genetic testing due to a personal or family history of phaeochromocytoma/paraganglioma. 876 patients (401 previously reported) had a germline mutation in SDHB/SDHC/SDHD (n=673/43/160). Tumour risks were correlated with in silico structural prediction analyses. RESULTS: Tumour risks analysis provided novel penetrance estimates and genotype-phenotype correlations. In addition to tumour type susceptibility differences for individual genes, we confirmed that the SDHD:p.Pro81Leu mutation has a distinct phenotype and identified increased age-related tumour risks with highly destabilising SDHB missense mutations. By Kaplan-Meier analysis, the penetrance (cumulative risk of clinically apparent tumours) in SDHB and (paternally inherited) SDHD mutation-positive non-probands (n=371/67 with detailed clinical information) by age 60 years was 21.8% (95% CI 15.2% to 27.9%) and 43.2% (95% CI 25.4% to 56.7%), respectively. Risk of malignant disease at age 60 years in non-proband SDHB mutation carriers was 4.2%(95% CI 1.1% to 7.2%). With retrospective cohort analysis to adjust for ascertainment, cumulative tumour risks for SDHB mutation carriers at ages 60 years and 80 years were 23.9% (95% CI 20.9% to 27.4%) and 30.6% (95% CI 26.8% to 34.7%). CONCLUSIONS: Overall risks of clinically apparent tumours for SDHB mutation carriers are substantially lower than initially estimated and will improve counselling of affected families. Specific genotype-tumour risk associations provides a basis for novel investigative strategies into succinate dehydrogenase-related mechanisms of tumourigenesis and the development of personalised management for SDHB/SDHC/SDHD mutation carriers.


Assuntos
Neoplasias das Glândulas Suprarrenais/genética , Proteínas de Membrana/genética , Paraganglioma/genética , Feocromocitoma/genética , Succinato Desidrogenase/genética , Neoplasias das Glândulas Suprarrenais/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Estudos de Associação Genética , Genótipo , Mutação em Linhagem Germinativa/genética , Heterozigoto , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto/genética , Paraganglioma/patologia , Feocromocitoma/patologia , Fatores de Risco , Caracteres Sexuais
6.
Lancet Oncol ; 19(2): 169-180, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29337092

RESUMO

BACKGROUND: Retrospective studies provide conflicting interpretations of the effect of inherited genetic factors on the prognosis of patients with breast cancer. The primary aim of this study was to determine the effect of a germline BRCA1 or BRCA2 mutation on breast cancer outcomes in patients with young-onset breast cancer. METHODS: We did a prospective cohort study of female patients recruited from 127 hospitals in the UK aged 40 years or younger at first diagnosis (by histological confirmation) of invasive breast cancer. Patients with a previous invasive malignancy (except non-melanomatous skin cancer) were excluded. Patients were identified within 12 months of initial diagnosis. BRCA1 and BRCA2 mutations were identified using blood DNA collected at recruitment. Clinicopathological data, and data regarding treatment and long-term outcomes, including date and site of disease recurrence, were collected from routine medical records at 6 months, 12 months, and then annually until death or loss to follow-up. The primary outcome was overall survival for all BRCA1 or BRCA2 mutation carriers (BRCA-positive) versus all non-carriers (BRCA-negative) at 2 years, 5 years, and 10 years after diagnosis. A prespecified subgroup analysis of overall survival was done in patients with triple-negative breast cancer. Recruitment was completed in 2008, and long-term follow-up is continuing. FINDINGS: Between Jan 24, 2000, and Jan 24, 2008, we recruited 2733 women. Genotyping detected a pathogenic BRCA mutation in 338 (12%) patients (201 with BRCA1, 137 with BRCA2). After a median follow-up of 8·2 years (IQR 6·0-9·9), 651 (96%) of 678 deaths were due to breast cancer. There was no significant difference in overall survival between BRCA-positive and BRCA-negative patients in multivariable analyses at any timepoint (at 2 years: 97·0% [95% CI 94·5-98·4] vs 96·6% [95·8-97·3]; at 5 years: 83·8% [79·3-87·5] vs 85·0% [83·5-86·4]; at 10 years: 73·4% [67·4-78·5] vs 70·1% [67·7-72·3]; hazard ratio [HR] 0·96 [95% CI 0·76-1·22]; p=0·76). Of 558 patients with triple-negative breast cancer, BRCA mutation carriers had better overall survival than non-carriers at 2 years (95% [95% CI 89-97] vs 91% [88-94]; HR 0·59 [95% CI 0·35-0·99]; p=0·047) but not 5 years (81% [73-87] vs 74% [70-78]; HR 1·13 [0·70-1·84]; p=0·62) or 10 years (72% [62-80] vs 69% [63-74]; HR 2·12 [0·82-5·49]; p= 0·12). INTERPRETATION: Patients with young-onset breast cancer who carry a BRCA mutation have similar survival as non-carriers. However, BRCA mutation carriers with triple-negative breast cancer might have a survival advantage during the first few years after diagnosis compared with non-carriers. Decisions about timing of additional surgery aimed at reducing future second primary-cancer risks should take into account patient prognosis associated with the first malignancy and patient preferences. FUNDING: Cancer Research UK, the UK National Cancer Research Network, the Wessex Cancer Trust, Breast Cancer Now, and the PPP Healthcare Medical Trust Grant.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Genes BRCA1 , Genes BRCA2 , Predisposição Genética para Doença/epidemiologia , Mutação em Linhagem Germinativa/genética , Adulto , Fatores Etários , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Estudos de Coortes , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Análise Multivariada , Avaliação de Resultados da Assistência ao Paciente , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Análise de Sobrevida , Neoplasias de Mama Triplo Negativas , Reino Unido , Adulto Jovem
7.
Hum Mol Genet ; 25(12): 2612-2620, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27008869

RESUMO

Endometrial cancer is the most common gynecological malignancy in the developed world. Although there is evidence of genetic predisposition to the disease, most of the genetic risk remains unexplained. We present the meta-analysis results of four genome-wide association studies (4907 cases and 11 945 controls total) in women of European ancestry. We describe one new locus reaching genome-wide significance (P < 5 × 10 -8) at 6p22.3 (rs1740828; P = 2.29 × 10 -8, OR = 1.20), providing evidence of an additional region of interest for genetic susceptibility to endometrial cancer.


Assuntos
Neoplasias do Endométrio/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Cromossomos Humanos Par 6/genética , Neoplasias do Endométrio/patologia , Feminino , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , População Branca/genética
8.
Hum Mol Genet ; 24(5): 1478-92, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25378557

RESUMO

Common variants in the hepatocyte nuclear factor 1 homeobox B (HNF1B) gene are associated with the risk of Type II diabetes and multiple cancers. Evidence to date indicates that cancer risk may be mediated via genetic or epigenetic effects on HNF1B gene expression. We previously found single-nucleotide polymorphisms (SNPs) at the HNF1B locus to be associated with endometrial cancer, and now report extensive fine-mapping and in silico and laboratory analyses of this locus. Analysis of 1184 genotyped and imputed SNPs in 6608 Caucasian cases and 37 925 controls, and 895 Asian cases and 1968 controls, revealed the best signal of association for SNP rs11263763 (P = 8.4 × 10(-14), odds ratio = 0.86, 95% confidence interval = 0.82-0.89), located within HNF1B intron 1. Haplotype analysis and conditional analyses provide no evidence of further independent endometrial cancer risk variants at this locus. SNP rs11263763 genotype was associated with HNF1B mRNA expression but not with HNF1B methylation in endometrial tumor samples from The Cancer Genome Atlas. Genetic analyses prioritized rs11263763 and four other SNPs in high-to-moderate linkage disequilibrium as the most likely causal SNPs. Three of these SNPs map to the extended HNF1B promoter based on chromatin marks extending from the minimal promoter region. Reporter assays demonstrated that this extended region reduces activity in combination with the minimal HNF1B promoter, and that the minor alleles of rs11263763 or rs8064454 are associated with decreased HNF1B promoter activity. Our findings provide evidence for a single signal associated with endometrial cancer risk at the HNF1B locus, and that risk is likely mediated via altered HNF1B gene expression.


Assuntos
Mapeamento Cromossômico , Neoplasias do Endométrio/genética , Loci Gênicos , Fator 1-beta Nuclear de Hepatócito/genética , Alelos , Estudos de Casos e Controles , Linhagem Celular Tumoral , Biologia Computacional , Bases de Dados Genéticas , Epigênese Genética , Feminino , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos , Fator 1-beta Nuclear de Hepatócito/metabolismo , Humanos , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Risco , População Branca/genética
9.
Histopathology ; 71(1): 42-52, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28165631

RESUMO

AIMS: Fumarate hydratase (FH)-deficient renal cell carcinoma (RCC) is a high-grade, aggressive tubulopapillary carcinoma, arising predominantly in the setting of the hereditary leiomyomatosis-RCC syndrome of familial uterocutaneous leiomyomatosis and deficiency of FH. In contrast, succinate dehydrogenase (SDH)-deficient RCC is a lower-grade oncocytic carcinoma with cytoplasmic flocculence/vacuolation and inclusions, arising mostly in individuals harbouring germline mutations of subunit B of the SDH complex (SDHB). Herein we aim to report the clinicopathologic features of a novel form of FH-deficient RCC showing a low grade oncocytic morphology, reminiscent of SDH-deficient RCC. METHODS AND RESULTS: These distinctive, low-grade oncocytic neoplasms, with solid, nested and focally tubular architecture (2-90 mm), arose in four males (aged 11-41 years). Uniform cytology of polygonal cells, with flocculent, vacuolated eosinophilic cytoplasm with scattered inclusions, fine chromatin, and inconspicuous nucleoli, was apparent. Despite these features suggestive of SDH-deficient RCC, each tumour was confirmed as an FH-deficient carcinoma with retained SDHB expression. One case showed a synchronous, anatomically separate, typical high-grade FH-deficient RCC; one other showed such a tumour at nephrectomy 4 years later. No progression has been noted at 3 and 7 years in the cases with only the SDH-like lesions; the two cases with separate, typical FH-deficient RCCs progressed. CONCLUSIONS: In summary, we characterize a novel oncocytic type of FH-deficient RCC with a striking resemblance to SDH-deficient RCC, posing a diagnostic challenge and raising concerns about sampling and multifocality for syndrome-associated cases under surveillance protocols.


Assuntos
Carcinoma de Células Renais/patologia , Fumarato Hidratase/deficiência , Neoplasias Renais/patologia , Adulto , Carcinoma de Células Renais/enzimologia , Criança , Humanos , Neoplasias Renais/enzimologia , Masculino , Succinato Desidrogenase
10.
JAMA ; 317(23): 2402-2416, 2017 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-28632866

RESUMO

Importance: The clinical management of BRCA1 and BRCA2 mutation carriers requires accurate, prospective cancer risk estimates. Objectives: To estimate age-specific risks of breast, ovarian, and contralateral breast cancer for mutation carriers and to evaluate risk modification by family cancer history and mutation location. Design, Setting, and Participants: Prospective cohort study of 6036 BRCA1 and 3820 BRCA2 female carriers (5046 unaffected and 4810 with breast or ovarian cancer or both at baseline) recruited in 1997-2011 through the International BRCA1/2 Carrier Cohort Study, the Breast Cancer Family Registry and the Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer, with ascertainment through family clinics (94%) and population-based studies (6%). The majority were from large national studies in the United Kingdom (EMBRACE), the Netherlands (HEBON), and France (GENEPSO). Follow-up ended December 2013; median follow-up was 5 years. Exposures: BRCA1/2 mutations, family cancer history, and mutation location. Main Outcomes and Measures: Annual incidences, standardized incidence ratios, and cumulative risks of breast, ovarian, and contralateral breast cancer. Results: Among 3886 women (median age, 38 years; interquartile range [IQR], 30-46 years) eligible for the breast cancer analysis, 5066 women (median age, 38 years; IQR, 31-47 years) eligible for the ovarian cancer analysis, and 2213 women (median age, 47 years; IQR, 40-55 years) eligible for the contralateral breast cancer analysis, 426 were diagnosed with breast cancer, 109 with ovarian cancer, and 245 with contralateral breast cancer during follow-up. The cumulative breast cancer risk to age 80 years was 72% (95% CI, 65%-79%) for BRCA1 and 69% (95% CI, 61%-77%) for BRCA2 carriers. Breast cancer incidences increased rapidly in early adulthood until ages 30 to 40 years for BRCA1 and until ages 40 to 50 years for BRCA2 carriers, then remained at a similar, constant incidence (20-30 per 1000 person-years) until age 80 years. The cumulative ovarian cancer risk to age 80 years was 44% (95% CI, 36%-53%) for BRCA1 and 17% (95% CI, 11%-25%) for BRCA2 carriers. For contralateral breast cancer, the cumulative risk 20 years after breast cancer diagnosis was 40% (95% CI, 35%-45%) for BRCA1 and 26% (95% CI, 20%-33%) for BRCA2 carriers (hazard ratio [HR] for comparing BRCA2 vs BRCA1, 0.62; 95% CI, 0.47-0.82; P=.001 for difference). Breast cancer risk increased with increasing number of first- and second-degree relatives diagnosed as having breast cancer for both BRCA1 (HR for ≥2 vs 0 affected relatives, 1.99; 95% CI, 1.41-2.82; P<.001 for trend) and BRCA2 carriers (HR, 1.91; 95% CI, 1.08-3.37; P=.02 for trend). Breast cancer risk was higher if mutations were located outside vs within the regions bounded by positions c.2282-c.4071 in BRCA1 (HR, 1.46; 95% CI, 1.11-1.93; P=.007) and c.2831-c.6401 in BRCA2 (HR, 1.93; 95% CI, 1.36-2.74; P<.001). Conclusions and Relevance: These findings provide estimates of cancer risk based on BRCA1 and BRCA2 mutation carrier status using prospective data collection and demonstrate the potential importance of family history and mutation location in risk assessment.


Assuntos
Neoplasias da Mama/genética , Genes BRCA1 , Genes BRCA2 , Mutação , Segunda Neoplasia Primária/genética , Neoplasias Ovarianas/genética , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Família , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Segunda Neoplasia Primária/epidemiologia , Neoplasias Ovarianas/epidemiologia , Estudos Prospectivos , Medição de Risco , Fatores de Tempo
11.
Recent Results Cancer Res ; 205: 29-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27075347

RESUMO

Thyroid cancers are largely divided into medullary (MTC) and non-medullary (NMTC) cancers , depending on the cell type of origin. Familial non-medullary thyroid cancer (FNMTC) comprises about 5-15% of NMTC and is a heterogeneous group of diseases, including both non-syndromic and syndromic forms. Non-syndromic FNMTC tends to manifest papillary thyroid carcinoma , usually multifocal and bilateral . Several high-penetrance genes for FNMTC have been identified, but they are often confined to a few or single families, and other susceptibility loci appear to play a small part, conferring only small increments in risk. Familial susceptibility is likely to be due to a combination of genetic and environmental influences. The current focus of research in FNMTC is to characterise the susceptibility genes and their role in carcinogenesis. FNMTC can also occur as a part of multitumour genetic syndromes such as familial adenomatous polyposis , Cowden's disease , Werner's syndrome and Carney complex . These tend to present at an early age and are multicentric and bilateral with distinct pathology. The clinical evaluation of these patients is similar to that for most patients with a thyroid nodule. Medullary thyroid cancer (MTC) arises from the parafollicular cells of the thyroid which release calcitonin. The familial form of MTC accounts for 20-25% of cases and presents as a part of the multiple endocrine neoplasia type 2 (MEN 2) syndromes or as a pure familial MTC (FMTC). They are caused by germline point mutations in the RET oncogene on chromosome 10q11.2. There is a clear genotype-phenotype correlation, and the aggressiveness of FMTC depends on the specific genetic mutation, which should determine the timing of surgery.


Assuntos
Síndromes Neoplásicas Hereditárias/diagnóstico , Síndromes Neoplásicas Hereditárias/terapia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/terapia , Predisposição Genética para Doença , Testes Genéticos , Genótipo , Humanos , Síndromes Neoplásicas Hereditárias/genética , Fenótipo , Neoplasias da Glândula Tireoide/genética
12.
PLoS Genet ; 9(5): e1003488, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23671423

RESUMO

Serrated adenomas form a distinct subtype of colorectal pre-malignant lesions that may progress to malignancy along a different molecular pathway than the conventional adenoma-carcinoma pathway. Previous studies have hypothesised that BRAF mutation and promoter hypermethylation plays a role, but the evidence for this is not robust. We aimed to carry out a whole-genome loss of heterozygosity analysis, followed by targeted promoter methylation and expression analysis to identify potential pathways in serrated adenomas. An initial panel of 9 sessile serrated adenomas (SSA) and one TSA were analysed using Illumina Goldengate HumanLinkage panel arrays to ascertain regions of loss of heterozygosity. This was verified via molecular inversion probe analysis and microsatellite analysis of a further 32 samples. Methylation analysis of genes of interest was carried out using methylation specific PCR (verified by pyrosequencing) and immunohistochemistry used to correlate loss of expression of genes of interest. All experiments used adenoma samples and normal tissue samples as control. SSA samples were found on whole-genome analysis to have consistent loss of heterozygosity at 4p15.1-4p15.31, which was not found in the sole TSA, adenomas, or normal tissues. Genes of interest in this region were PDCH7 and SLIT2, and combined MSP/IHC analysis of these genes revealed significant loss of SLIT2 expression associated with promoter methylation of SLIT2. Loss of expression of SLIT2 by promoter hypermethylation and loss of heterozygosity events is significantly associated with serrated adenoma development, and SLIT2 may represent a epimutated tumour suppressor gene according to the Knudson "two hit" hypothesis.


Assuntos
Adenoma/genética , Neoplasias Colorretais/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas do Tecido Nervoso/genética , Adenoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/patologia , Metilação de DNA , Feminino , Regulação Neoplásica da Expressão Gênica , Ligação Genética , Humanos , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade
13.
Assist Technol ; 28(2): 115-25, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26817495

RESUMO

Masking is widely used in the management of tinnitus, however, masking at the perceived spatial location of tinnitus has not been investigated. This article examines the development of a method for the spatial masking of tinnitus. This report consists of three studies: Study I is a proof of concept study comparing customized spatial masking to conventional bilateral masking; Study II is a prototype evaluation in which the spatial masking paradigm was compared to a bilaterally equal masker using iPods connected to hearing aids in a 4-week cross-over trial; and Study III is a 4-month crossover pilot study-using prototype hearing aid-based maskers, and in which three-dimensional (3D) masking (2 months) was compared to a Tinnitus Retraining Therapy (2 months). There was a preference for the 3D masking stimulus across all three studies. Individual changes in the Tinnitus Handicap Inventory (THI) after 2 weeks of trial (Study II) and Tinnitus Functional Index (TFI) after 2 months of trial (Study III) were observed without large group differences. The spatial masking concept was piloted successfully. The qualitative and quantitative results obtained indicate directions for future clinical trials and therapy development. This study indicates that spatial masking of tinnitus is feasible, of benefit to many participants, and warrants further trials.


Assuntos
Auxiliares de Audição , Zumbido/terapia , Adulto , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Inquéritos e Questionários , Adulto Jovem
14.
Hum Mol Genet ; 22(14): 2820-8, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23528559

RESUMO

Accurate duplication of DNA prior to cell division is essential to suppress mutagenesis and tumour development. The high fidelity of eukaryotic DNA replication is due to a combination of accurate incorporation of nucleotides into the nascent DNA strand by DNA polymerases, the recognition and removal of mispaired nucleotides (proofreading) by the exonuclease activity of DNA polymerases δ and ε, and post-replication surveillance and repair of newly synthesized DNA by the mismatch repair (MMR) apparatus. While the contribution of defective MMR to neoplasia is well recognized, evidence that faulty DNA polymerase activity is important in cancer development has been limited. We have recently shown that germline POLE and POLD1 exonuclease domain mutations (EDMs) predispose to colorectal cancer (CRC) and, in the latter case, to endometrial cancer (EC). Somatic POLE mutations also occur in 5-10% of sporadic CRCs and underlie a hypermutator, microsatellite-stable molecular phenotype. We hypothesized that sporadic ECs might also acquire somatic POLE and/or POLD1 mutations. Here, we have found that missense POLE EDMs with good evidence of pathogenic effects are present in 7% of a set of 173 endometrial cancers, although POLD1 EDMs are uncommon. The POLE mutations localized to highly conserved residues and were strongly predicted to affect proofreading. Consistent with this, POLE-mutant tumours were hypermutated, with a high frequency of base substitutions, and an especially large relative excess of G:C>T:A transversions. All POLE EDM tumours were microsatellite stable, suggesting that defects in either DNA proofreading or MMR provide alternative mechanisms to achieve genomic instability and tumourigenesis.


Assuntos
DNA Polimerase III/genética , DNA Polimerase II/genética , Neoplasias do Endométrio/enzimologia , Mutação , Adulto , Idoso , Sequência de Aminoácidos , DNA Polimerase II/química , DNA Polimerase II/metabolismo , DNA Polimerase III/química , DNA Polimerase III/metabolismo , Neoplasias do Endométrio/genética , Feminino , Mutação em Linhagem Germinativa , Humanos , Repetições de Microssatélites , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteínas de Ligação a Poli-ADP-Ribose , Estrutura Terciária de Proteína , Alinhamento de Sequência , Adulto Jovem
15.
Hum Genet ; 134(2): 231-45, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25487306

RESUMO

Several studies have reported associations between multiple cancer types and single-nucleotide polymorphisms (SNPs) on chromosome 5p15, which harbours TERT and CLPTM1L, but no such association has been reported with endometrial cancer. To evaluate the role of genetic variants at the TERT-CLPTM1L region in endometrial cancer risk, we carried out comprehensive fine-mapping analyses of genotyped and imputed SNPs using a custom Illumina iSelect array which includes dense SNP coverage of this region. We examined 396 SNPs (113 genotyped, 283 imputed) in 4,401 endometrial cancer cases and 28,758 controls. Single-SNP and forward/backward logistic regression models suggested evidence for three variants independently associated with endometrial cancer risk (P = 4.9 × 10(-6) to P = 7.7 × 10(-5)). Only one falls into a haplotype previously associated with other cancer types (rs7705526, in TERT intron 1), and this SNP has been shown to alter TERT promoter activity. One of the novel associations (rs13174814) maps to a second region in the TERT promoter and the other (rs62329728) is in the promoter region of CLPTM1L; neither are correlated with previously reported cancer-associated SNPs. Using TCGA RNASeq data, we found significantly increased expression of both TERT and CLPTM1L in endometrial cancer tissue compared with normal tissue (TERT P = 1.5 × 10(-18), CLPTM1L P = 1.5 × 10(-19)). Our study thus reports a novel endometrial cancer risk locus and expands the spectrum of cancer types associated with genetic variation at 5p15, further highlighting the importance of this region for cancer susceptibility.


Assuntos
Cromossomos Humanos Par 5/genética , Loci Gênicos , Proteínas de Membrana/genética , Modelos Genéticos , Proteínas de Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Telomerase/genética , Cromossomos Humanos Par 5/metabolismo , Bases de Dados de Ácidos Nucleicos , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Haplótipos , Humanos , Proteínas de Membrana/biossíntese , Proteínas de Neoplasias/biossíntese , Regiões Promotoras Genéticas , Fatores de Risco , Telomerase/biossíntese
16.
J Pathol ; 229(5): 697-704, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23096130

RESUMO

Changes in DNA methylation, whether hypo- or hypermethylation, have been shown to be associated with the progression of colorectal cancer. Methylation changes substantially in the progression from normal mucosa to adenoma and to carcinoma. This phenomenon has not been studied extensively and studies have been restricted to individual CpG islands, rather than taking a whole-genome approach. We aimed to study genome-wide methylation changes in colorectal cancer. We obtained 10 fresh-frozen normal tissue-cancer sample pairs, and five fresh-frozen adenoma samples. These were run on the lllumina HumanMethylation27 whole-genome methylation analysis system. Differential methylation between normal tissue, adenoma and carcinoma was analysed using Bayesian regression modelling, gene set enrichment analysis (GSEA) and hierarchical clustering (HC). The highest-rated individual gene for differential methylation in carcinomas versus normal tissue and adenomas versus normal tissue was GRASP (padjusted = 1.59 × 10(-5) , BF = 12.62, padjusted = 1.68 × 10(-6) , BF = 14.53). The highest-rated gene when comparing carcinomas versus adenomas was ATM (padjusted = 2.0 × 10(-4) , BF = 10.17). Hierarchical clustering demonstrated poor clustering by the CIMP criteria for methylation. GSEA demonstrated methylation changes in the Netrin-DCC and SLIT-ROBO pathways. Widespread changes in DNA methylation are seen in the transition from adenoma to carcinoma. The finding that GRASP, which encodes the general receptor for phosphoinositide 1-associated scaffold protein, was differentially methylated in colorectal cancer is interesting. This may be a potential biomarker for colorectal cancer.


Assuntos
Adenoma/genética , Biomarcadores Tumorais/genética , Carcinoma/genética , Proteínas de Transporte/genética , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/genética , Metilação de DNA , Proteínas de Membrana/genética , Adenoma/patologia , Idoso , Idoso de 80 Anos ou mais , Teorema de Bayes , Carcinoma/patologia , Estudos de Casos e Controles , Transformação Celular Neoplásica/patologia , Análise por Conglomerados , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Modelos Genéticos , Mutação , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras) , Proteínas ras/genética
17.
Gut ; 62(6): 812-23, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23408351

RESUMO

Lynch syndrome (LS) is characterised by the development of colorectal cancer, endometrial cancer and various other cancers, and is caused by a mutation in one of the mismatch repair genes: MLH1, MSH2, MSH6 or PMS2. In 2007, a group of European experts (the Mallorca group) published guidelines for the clinical management of LS. Since then substantial new information has become available necessitating an update of the guidelines. In 2011 and 2012 workshops were organised in Palma de Mallorca. A total of 35 specialists from 13 countries participated in the meetings. The first step was to formulate important clinical questions. Then a systematic literature search was performed using the Pubmed database and manual searches of relevant articles. During the workshops the outcome of the literature search was discussed in detail. The guidelines described in this paper may be helpful for the appropriate management of families with LS. Prospective controlled studies should be undertaken to improve further the care of these families.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/terapia , Adulto , Idoso , Colonoscopia/normas , Neoplasias Colorretais Hereditárias sem Polipose/complicações , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Neoplasias/etiologia , Neoplasias/genética , Neoplasias/terapia , Vigilância em Saúde Pública , Fatores de Risco , Adulto Jovem
18.
Hum Mutat ; 34(12): 1650-61, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24000165

RESUMO

Investigation of rare familial forms of renal cell carcinoma (RCC) has led to the identification of genes such as VHL and MET that are also implicated in the pathogenesis of sporadic RCC. In order to identify a novel candidate renal tumor suppressor gene, we characterized the breakpoints of a constitutional balanced translocation, t(5;19)(p15.3;q12), associated with familial RCC and found that a previously uncharacterized gene UBE2QL1 was disrupted by the chromosome 5 breakpoint. UBE2QL1 mRNA expression was downregulated in 78.6% of sporadic RCC and, although no intragenic mutations were detected, gene deletions and promoter region hypermethylation were detected in 17.3% and 20.3%, respectively, of sporadic RCC. Reexpression of UBE2QL1 in a deficient RCC cell line suppressed anchorage-independent growth. UBE2QL1 shows homology to the E2 class of ubiquitin conjugating enzymes and we found that (1) UBE2QL1 possesses an active-site cysteine (C88) that is monoubiquitinated in vivo, and (2) UBE2QL1 interacts with FBXW7 (an F box protein providing substrate recognition to the SCF E3 ubiquitin ligase) and facilitates the degradation of the known FBXW7 targets, CCNE1 and mTOR. These findings suggest UBE2QL1 as a novel candidate renal tumor suppressor gene.


Assuntos
Genes Supressores de Tumor , Predisposição Genética para Doença , Neoplasias Renais/genética , Translocação Genética , Enzimas de Conjugação de Ubiquitina/genética , Adulto , Sequência de Bases , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Pontos de Quebra do Cromossomo , Cromossomos Humanos Par 19 , Cromossomos Humanos Par 5 , Metilação de DNA , Epigênese Genética , Proteínas F-Box/metabolismo , Proteína 7 com Repetições F-Box-WD , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/metabolismo , Dados de Sequência Molecular , Ligação Proteica , Transporte Proteico , Enzimas de Conjugação de Ubiquitina/química , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
19.
Clin Endocrinol (Oxf) ; 78(6): 898-906, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23072324

RESUMO

OBJECTIVES: Research studies have reported that about a third of individuals with phaeochromocytoma/paraganglioma (PPGL) have an inherited predisposition, although the frequency of specific mutations can vary between populations. We evaluated VHL, SDHB and SDHD mutation testing in cohorts of patients with non-syndromic PPGL and head and neck paraganglioma (HNPGL). DESIGN: Prospective, observational evaluation of NHS practice. PATIENTS: Individuals with PPGL/HNPGL referred to a supraregional genetics testing service over a 10-year period. MEASUREMENTS: Clinical (age, tumour site, malignancy, etc.), mutation frequencies and characteristics. RESULTS: A total of 501 probands with PPGL (n = 413) or HNPGL (n = 88) were studied. Thirty-one percent of patients with PPGL presented had a pathogenic mutation in SDHB, SDHD or VHL. Mutation detection rates were highest in those with a positive family history (62%), malignancy (53%), multiple tumours (33%) or PGL (44%). Twenty-eight percent of individuals with a single sporadic phaeochromocytoma had a mutation. Overall, 63% of patients with HNPGL had a mutation (92% of those with a family history, 89% of those with multicentric tumours and 34% of those with a single sporadic HNPGL). Penetrance was calculated in 121 SDHB mutation-positive probands and 187 of their mutation-positive relatives. Most relatives were asymptomatic and lifetime penetrance in non-proband SDHB mutation carriers was <50%. CONCLUSIONS: Practice-based evaluations of genetic testing in PPGL reveal high mutation detection rates. Although clinical criteria can be used to prioritize mutation testing, mutations were detected in 'low risk groups' indicating a need for comprehensive and inexpensive genetic testing strategies for PPGL and HNPGL.


Assuntos
Neoplasias das Glândulas Suprarrenais/genética , Predisposição Genética para Doença/genética , Neoplasias de Cabeça e Pescoço/genética , Paraganglioma/genética , Feocromocitoma/genética , Succinato Desidrogenase/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Testes Genéticos , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
20.
Breast J ; 19(2): 193-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23294250

RESUMO

Lynch Syndrome, an autosomal dominantly inherited cancer predisposition syndrome is not typically associated with development of breast cancer. We present two cases of loss of mismatch protein expression in breast cancer cases in patients with Lynch Syndrome and discuss the literature surrounding the subject.


Assuntos
Neoplasias da Mama/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Proteínas de Ligação a DNA/genética , Proteína 2 Homóloga a MutS/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Idoso de 80 Anos ou mais , Neoplasias Colorretais Hereditárias sem Polipose/cirurgia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Proteína 1 Homóloga a MutL , Proteínas Nucleares/genética
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