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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.
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
3.
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
4.
Cancer Epidemiol Biomarkers Prev ; 25(11): 1503-1510, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27550749

RESUMO

BACKGROUND: The strongest known risk factor for endometrial cancer is obesity. To determine whether SNPs associated with increased body mass index (BMI) or waist-hip ratio (WHR) are associated with endometrial cancer risk, independent of measured BMI, we investigated relationships between 77 BMI and 47 WHR SNPs and endometrial cancer in 6,609 cases and 37,926 country-matched controls. METHODS: Logistic regression analysis and fixed effects meta-analysis were used to test for associations between endometrial cancer risk and (i) individual BMI or WHR SNPs, (ii) a combined weighted genetic risk score (wGRS) for BMI or WHR. Causality of BMI for endometrial cancer was assessed using Mendelian randomization, with BMIwGRS as instrumental variable. RESULTS: The BMIwGRS was significantly associated with endometrial cancer risk (P = 3.4 × 10-17). Scaling the effect of the BMIwGRS on endometrial cancer risk by its effect on BMI, the endometrial cancer OR per 5 kg/m2 of genetically predicted BMI was 2.06 [95% confidence interval (CI), 1.89-2.21], larger than the observed effect of BMI on endometrial cancer risk (OR = 1.55; 95% CI, 1.44-1.68, per 5 kg/m2). The association attenuated but remained significant after adjusting for BMI (OR = 1.22; 95% CI, 1.10-1.39; P = 5.3 × 10-4). There was evidence of directional pleiotropy (P = 1.5 × 10-4). BMI SNP rs2075650 was associated with endometrial cancer at study-wide significance (P < 4.0 × 10-4), independent of BMI. Endometrial cancer was not significantly associated with individual WHR SNPs or the WHRwGRS. CONCLUSIONS: BMI, but not WHR, is causally associated with endometrial cancer risk, with evidence that some BMI-associated SNPs alter endometrial cancer risk via mechanisms other than measurable BMI. IMPACT: The causal association between BMI SNPs and endometrial cancer has possible implications for endometrial cancer risk modeling. Cancer Epidemiol Biomarkers Prev; 25(11); 1503-10. ©2016 AACR.


Assuntos
Índice de Massa Corporal , Neoplasias do Endométrio/etiologia , Predisposição Genética para Doença , Análise da Randomização Mendeliana , Obesidade/complicações , Polimorfismo de Nucleotídeo Único , Neoplasias do Endométrio/genética , Feminino , Humanos , Obesidade/genética , Relação Cintura-Quadril
5.
J Clin Oncol ; 33(31): 3591-7, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26282643

RESUMO

PURPOSE: In the general population, increased adiposity is a significant risk factor for colorectal cancer (CRC), but whether obesity has similar effects in those with hereditary CRC is uncertain. This prospective study investigated the association between body mass index and cancer risk in patients with Lynch syndrome (LS). PATIENTS AND METHODS: Participants with LS were recruited to the CAPP2 study, in which they were randomly assigned to receive aspirin 600 mg per day or aspirin placebo, plus resistant starch 30 g per day or starch placebo (2 × 2 factorial design). Mean intervention period was 25.0 months, and mean follow-up was 55.7 months. RESULTS: During follow-up, 55 of 937 participants developed CRC. For obese participants, CRC risk was 2.41× (95% CI, 1.22 to 4.85) greater than for underweight and normal-weight participants (reference group), and CRC risk increased by 7% for each 1-kg/m(2) increase in body mass index. The risk of all LS-related cancers in obese people was 1.77× (95% CI, 1.06 to 2.96; P = .03) greater than for the reference group. In subgroup analysis, obesity was associated with 3.72× (95% CI, 1.41 to 9.81) greater CRC risk in patients with LS with MLH1 mutation, but no excess risk was observed in those with MSH2 or MSH6 mutation (P = .5). The obesity-related excess CRC risk was confined to those randomly assigned to the aspirin placebo group (adjusted hazard ratio, 2.75; 95% CI, 1.12 to 6.79; P = .03). CONCLUSION: Obesity is associated with substantially increased CRC risk in patients with LS, but this risk is abrogated in those taking aspirin. Such patients are likely to benefit from obesity prevention and/or regular aspirin.


Assuntos
Aspirina/uso terapêutico , Índice de Massa Corporal , Neoplasias Colorretais Hereditárias sem Polipose/complicações , Neoplasias Colorretais/complicações , Neoplasias Colorretais/prevenção & controle , Obesidade/complicações , Proteínas Adaptadoras de Transdução de Sinal/genética , Adiposidade , Adulto , Anti-Inflamatórios não Esteroides/uso terapêutico , Peso Corporal , Neoplasias Colorretais/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Proteínas de Ligação a DNA/genética , Feminino , Seguimentos , Heterozigoto , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS/genética , Mutação , Proteínas Nucleares/genética , Estudos Prospectivos , Fatores de Risco
6.
J Clin Endocrinol Metab ; 99(7): E1300-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24708097

RESUMO

CONTEXT: Autosomal dominant hypocalcemia (ADH) types 1 and 2 are due to calcium-sensing receptor (CASR) and G-protein subunit-α11 (GNA11) gain-of-function mutations, respectively, whereas CASR and GNA11 loss-of-function mutations result in familial hypocalciuric hypercalcemia (FHH) types 1 and 2, respectively. Loss-of-function mutations of adaptor protein-2 sigma subunit (AP2σ 2), encoded by AP2S1, cause FHH3, and we therefore sought for gain-of-function AP2S1 mutations that may cause an additional form of ADH, which we designated ADH3. OBJECTIVE: The objective of the study was to investigate the hypothesis that gain-of-function AP2S1 mutations may cause ADH3. DESIGN: The sample size required for the detection of at least one mutation with a greater than 95% likelihood was determined by binomial probability analysis. Nineteen patients (including six familial cases) with hypocalcemia in association with low or normal serum PTH concentrations, consistent with ADH, but who did not have CASR or GNA11 mutations, were ascertained. Leukocyte DNA was used for sequence and copy number variation analysis of AP2S1. RESULTS: Binomial probability analysis, using the assumption that AP2S1 mutations would occur in hypocalcemic patients at a prevalence of 20%, which is observed in FHH patients without CASR or GNA11 mutations, indicated that the likelihood of detecting at least one AP2S1 mutation was greater than 95% and greater than 98% in sample sizes of 14 and 19 hypocalcemic patients, respectively. AP2S1 mutations and copy number variations were not detected in the 19 hypocalcemic patients. CONCLUSION: The absence of AP2S1 abnormalities in hypocalcemic patients, suggests that ADH3 may not occur or otherwise represents a rare hypocalcemic disorder.


Assuntos
Complexo 2 de Proteínas Adaptadoras/genética , Subunidades sigma do Complexo de Proteínas Adaptadoras/genética , Hipercalciúria/genética , Hipocalcemia/genética , Hipoparatireoidismo/congênito , Adulto , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Frequência do Gene , Humanos , Hipoparatireoidismo/genética , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
7.
Fam Cancer ; 13(1): 57-63, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23934601

RESUMO

Patients with germline PTEN mutations are at high risk of developing benign and malignant tumours. We aimed to evaluate the cumulative risk of several types of cancer and of dysplastic cerebellar gangliocytoma (Lhermitte-Duclos disease, LDD). In addition, genotype-phenotype correlations in PTEN hamartoma tumour syndrome (PHTS) were assessed. Data on patients with PTEN mutations were collected from clinical genetic centres in Western Europe, Australia, and the USA. The cumulative risk of developing cancers of the breast, thyroid, endometrium, skin, kidneys, colorectum, and lungs, and also LDD was calculated by Kaplan-Meier methods. Associations between mutations and cancer were assessed by Chi square means. A total of 180 germline PTEN mutation carriers, 81 males (45%), from nine countries were included. The cumulative risk of developing any cancer and/or LDD at age 60 was 56% for males and 87% for females (p = 0.001). Females had significant higher risks of developing breast cancer, thyroid cancer, and LDD than males. The only genotype-phenotype correlation identified was a lower frequency of thyroid cancer in patients with missense mutations (p = 0.014). In conclusion, PHTS patients, particularly females, have a substantial risk of developing one or more tumours from a broad tumour spectrum. Major genotype-phenotype associations could not be identified.


Assuntos
Síndrome do Hamartoma Múltiplo/genética , Neoplasias/genética , PTEN Fosfo-Hidrolase/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Heterozigoto , Humanos , Lactente , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Síndrome , Neoplasias da Glândula Tireoide/genética , Adulto Jovem
9.
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
11.
J Clin Endocrinol Metab ; 98(7): E1248-56, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23666964

RESUMO

CONTEXT: Pheochromocytomas and paragangliomas are notable for a high frequency of inherited cases, many of which present as apparently sporadic tumors. OBJECTIVE: The objective of this study was to establish a comprehensive next generation sequencing (NGS)-based strategy for the diagnosis of patients with pheochromocytoma and paraganglioma by testing simultaneously for mutations in MAX, RET, SDHA, SDHB, SDHC, SDHD, SDHAF2, TMEM127, and VHL. DESIGN: After the methodology for the assay was designed and established, it was validated on DNA samples with known genotype and then patients were studied prospectively. SETTING: The study was performed in a diagnostic genetics laboratory. PATIENTS: DNA samples from 205 individuals affected with adrenal or extraadrenal pheochromocytoma/head and neck paraganglioma (PPGL/HNPGL) were analyzed. A proof-of-principle study was performed using 85 samples known to contain a variant in 1 or more of the genes to be tested, followed by prospective analysis of an additional 120 samples. MAIN OUTCOME MEASURES: We assessed the ability to use an NGS-based method to perform comprehensive analysis of genes implicated in inherited PPGL/HNPGL. RESULTS: The proof-of-principle study showed that the NGS assay and analysis gave a sensitivity of 98.7%. A pathogenic mutation was identified in 16.6% of the prospective analysis cohort of 120 patients. CONCLUSIONS: A comprehensive NGS-based strategy for the analysis of genes associated with predisposition to PPGL and HNPGL was established, validated, and introduced into diagnostic service. The new assay provides simultaneous analysis of 9 genes and allows more rapid and cost-effective mutation detection than the previously used conventional Sanger sequencing-based methodology.


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Mutação em Linhagem Germinativa , Neoplasias de Cabeça e Pescoço/diagnóstico , Paraganglioma/diagnóstico , Feocromocitoma/diagnóstico , Neoplasias das Glândulas Suprarrenais/economia , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/metabolismo , Estudos de Coortes , Redução de Custos , Custos e Análise de Custo , Análise Mutacional de DNA/economia , Predisposição Genética para Doença , Testes Genéticos/economia , Testes Genéticos/métodos , Neoplasias de Cabeça e Pescoço/economia , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Custos de Cuidados de Saúde , Humanos , Paraganglioma/economia , Paraganglioma/genética , Paraganglioma/metabolismo , Feocromocitoma/economia , Feocromocitoma/genética , Feocromocitoma/metabolismo , Estudos Prospectivos , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteínas Proto-Oncogênicas c-ret/química , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas c-ret/metabolismo , Sensibilidade e Especificidade , Succinato Desidrogenase/química , Succinato Desidrogenase/genética , Succinato Desidrogenase/metabolismo , Reino Unido , Proteína Supressora de Tumor Von Hippel-Lindau/química , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo
12.
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
13.
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
14.
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
15.
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
16.
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
17.
Oncotarget ; 3(11): 1348-55, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23154512

RESUMO

Repair of double strand DNA breaks (DSBs) is pivotal in maintaining normal cell division and disruption of this system has been shown to be a key factor in carcinogenesis. Loss of expression of the DSB repair proteins have previously been shown to be associated with poorer survival in colorectal cancer. We wished to ascertain the relationship of altered expression of the DSB repair proteins γ-H2AX (gamma-H2AX), ATM and Ku70 with biological and clinico-pathological features of colorectal cancer. 908 tumours from the VICTOR clinical trial of stage II/III colorectal cancer were analysed for expression of γ-H2AX, ATM and Ku70 using immunohistochemistry. Expression levels were correlated with CIN and with disease-free survival, correcting for microsatellite instability, BRAF/KRAS mutation status, Dukes stage, chemo/radiotherapy, age, gender and tumour location. Down-regulated Ku70 expression was associated with chromosomal instability (p=0.029) in colorectal cancer. Reduced ATM expression was an independent marker of poor disease-free survival (HR=1.67, 95% CI 1.11-2.50, p=0.015). For Ku70, further studies are required to investigate the potential relationship of non-homologous end joining with chromosomal instability. Loss of ATM expression might serve as a biomarker of poor prognosis in colorectal cancer.


Assuntos
Proteínas de Ciclo Celular/deficiência , Instabilidade Cromossômica , Neoplasias Colorretais/genética , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Proteínas de Ligação a DNA/deficiência , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Supressoras de Tumor/deficiência , Antígenos Nucleares/biossíntese , Antígenos Nucleares/genética , Proteínas Mutadas de Ataxia Telangiectasia , Biomarcadores Tumorais/deficiência , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Neoplasias Colorretais/metabolismo , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Intervalo Livre de Doença , Regulação para Baixo , Genótipo , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Autoantígeno Ku , Polimorfismo Genético , Prognóstico , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Serina-Treonina Quinases/genética , Ensaios Clínicos Controlados Aleatórios como Assunto , Proteínas Supressoras de Tumor/biossíntese , Proteínas Supressoras de Tumor/genética
18.
Fam Cancer ; 11(3): 509-18, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22773173

RESUMO

Approximately 25 % of mismatch repair (MMR) variants are exonic nucleotide substitutions. Some result in the substitution of one amino acid for another in the protein sequence, so-called missense variants, while others are silent. The interpretation of the effect of missense and silent variants as deleterious or neutral is challenging. Pre-symptomatic testing for clinical use is not recommended for relatives of individuals with variants classified as 'of uncertain significance'. These relatives, including non-carriers, are considered at high-risk as long as the contribution of the variant to disease causation cannot be determined. This results in continuing anxiety, and the application of potentially unnecessary screening and prophylactic interventions. We encountered a large Irish Lynch syndrome kindred that carries the c.544A>G (p.Arg182Gly) alteration in the MLH1 gene and we undertook to study the variant. The clinical significance of the variant remains unresolved in the literature. Data are presented on cancer incidence within five kindreds with the same germline missense variant in the MLH1 MMR gene. Extensive testing of relevant family members in one kindred, a review of the literature, review of online MMR mutation databases and use of in silico phenotype prediction tools were undertaken to study the significance of this variant. Clinical, histological, immunohistochemical and molecular evidence from these families and other independent clinical and scientific evidence indicates that the MLH1 p.Arg182Gly (c.544A>G) change causes Lynch syndrome and supports reclassification of the variant as pathogenic.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Mutação , Proteínas Nucleares/genética , Adulto , Idoso , Feminino , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Linhagem
19.
Lancet ; 378(9809): 2081-7, 2011 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-22036019

RESUMO

BACKGROUND: Observational studies report reduced colorectal cancer in regular aspirin consumers. Randomised controlled trials have shown reduced risk of adenomas but none have employed prevention of colorectal cancer as a primary endpoint. The CAPP2 trial aimed to investigate the antineoplastic effects of aspirin and a resistant starch in carriers of Lynch syndrome, the major form of hereditary colorectal cancer; we now report long-term follow-up of participants randomly assigned to aspirin or placebo. METHODS: In the CAPP2 randomised trial, carriers of Lynch syndrome were randomly assigned in a two-by-two factorial design to 600 mg aspirin or aspirin placebo or 30 g resistant starch or starch placebo, for up to 4 years. Randomisation was in blocks of 16 with provision for optional single-agent randomisation and extended postintervention double-blind follow-up; participants and investigators were masked to treatment allocation. The primary endpoint was development of colorectal cancer. Analysis was by intention to treat and per protocol. This trial is registered, ISRCTN59521990. RESULTS: 861 participants were randomly assigned to aspirin or aspirin placebo. At a mean follow-up of 55·7 months, 48 participants had developed 53 primary colorectal cancers (18 of 427 randomly assigned to aspirin, 30 of 434 to aspirin placebo). Intention-to-treat analysis of time to first colorectal cancer showed a hazard ratio (HR) of 0·63 (95% CI 0·35-1·13, p=0·12). Poisson regression taking account of multiple primary events gave an incidence rate ratio (IRR) of 0·56 (95% CI 0·32-0·99, p=0·05). For participants completing 2 years of intervention (258 aspirin, 250 aspirin placebo), per-protocol analysis yielded an HR of 0·41 (0·19-0·86, p=0·02) and an IRR of 0·37 (0·18-0·78, p=0·008). No data for adverse events were available postintervention; during the intervention, adverse events did not differ between aspirin and placebo groups. INTERPRETATION: 600 mg aspirin per day for a mean of 25 months substantially reduced cancer incidence after 55·7 months in carriers of hereditary colorectal cancer. Further studies are needed to establish the optimum dose and duration of aspirin treatment. FUNDING: European Union; Cancer Research UK; Bayer Corporation; National Starch and Chemical Co; UK Medical Research Council; Newcastle Hospitals trustees; Cancer Council of Victoria Australia; THRIPP South Africa; The Finnish Cancer Foundation; SIAK Switzerland; Bayer Pharma.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Aspirina/uso terapêutico , Neoplasias Colorretais Hereditárias sem Polipose/prevenção & controle , Heterozigoto , Adenoma/prevenção & controle , Quimioprevenção , Neoplasias Colorretais Hereditárias sem Polipose/genética , Carboidratos da Dieta/uso terapêutico , Método Duplo-Cego , Humanos , Amido/uso terapêutico
20.
Hum Mutat ; 31(11): 1205-15, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20725929

RESUMO

The MUTYH gene encodes a DNA glycosylase involved in base excision repair (BER). Biallelic pathogenic MUTYH variants have been associated with colorectal polyposis and cancer. The pathogenicity of a few variants is beyond doubt, including c.536A4G/p.Tyr179Cys and c.1187G4A/p.Gly396Asp (previously c.494A4G/p.Tyr165Cys and c.1145G4A/p.Gly382Asp).However, for a substantial fraction of the detected variants, the clinical significance remains uncertain,compromising molecular diagnostics and thereby genetic counseling. We have established an interactive MUTYH gene sequence variant database (www.lovd.nl/MUTYH) with the aim of collecting and sharing MUTYH genotype and phenotype data worldwide. To support standard variant description, we chose NM_001128425.1 as the reference sequence. The database includes records with variants per individual, linked to available phenotype and geographic origin data as well as records with in vitro functional and in silico test data. As of April 2010, the database contains 1968 published and 423 unpublished submitted entries, and 230 and 61 unique variants,respectively. This open-access repository allows all involved to quickly share all variants encountered and communicate potential consequences, which will be especially useful to classify variants of uncertain significance.


Assuntos
DNA Glicosilases/genética , Bases de Dados Genéticas , Variação Genética , Polipose Adenomatosa do Colo/genética , Processamento Alternativo , Sequência de Aminoácidos , Sequência de Bases , DNA/genética , DNA Glicosilases/química , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Dados de Sequência Molecular , Mutação , Países Baixos , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Estrutura Terciária de Proteína
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