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1.
Nature ; 629(8013): 910-918, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38693263

RESUMO

International differences in the incidence of many cancer types indicate the existence of carcinogen exposures that have not yet been identified by conventional epidemiology make a substantial contribution to cancer burden1. In clear cell renal cell carcinoma, obesity, hypertension and tobacco smoking are risk factors, but they do not explain the geographical variation in its incidence2. Underlying causes can be inferred by sequencing the genomes of cancers from populations with different incidence rates and detecting differences in patterns of somatic mutations. Here we sequenced 962 clear cell renal cell carcinomas from 11 countries with varying incidence. The somatic mutation profiles differed between countries. In Romania, Serbia and Thailand, mutational signatures characteristic of aristolochic acid compounds were present in most cases, but these were rare elsewhere. In Japan, a mutational signature of unknown cause was found in more than 70% of cases but in less than 2% elsewhere. A further mutational signature of unknown cause was ubiquitous but exhibited higher mutation loads in countries with higher incidence rates of kidney cancer. Known signatures of tobacco smoking correlated with tobacco consumption, but no signature was associated with obesity or hypertension, suggesting that non-mutagenic mechanisms of action underlie these risk factors. The results of this study indicate the existence of multiple, geographically variable, mutagenic exposures that potentially affect tens of millions of people and illustrate the opportunities for new insights into cancer causation through large-scale global cancer genomics.


Assuntos
Carcinoma de Células Renais , Exposição Ambiental , Geografia , Neoplasias Renais , Mutagênicos , Mutação , Feminino , Humanos , Masculino , Ácidos Aristolóquicos/efeitos adversos , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/epidemiologia , Carcinoma de Células Renais/induzido quimicamente , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Genoma Humano/genética , Genômica , Hipertensão/epidemiologia , Incidência , Japão/epidemiologia , Neoplasias Renais/genética , Neoplasias Renais/epidemiologia , Neoplasias Renais/induzido quimicamente , Mutagênicos/efeitos adversos , Obesidade/epidemiologia , Fatores de Risco , Romênia/epidemiologia , Sérvia/epidemiologia , Tailândia/epidemiologia , Fumar Tabaco/efeitos adversos , Fumar Tabaco/genética
2.
Mol Syst Biol ; 20(6): 719-740, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38580884

RESUMO

Tumor suppressor p53 (TP53) is frequently mutated in cancer, often resulting not only in loss of its tumor-suppressive function but also acquisition of dominant-negative and even oncogenic gain-of-function traits. While wild-type p53 levels are tightly regulated, mutants are typically stabilized in tumors, which is crucial for their oncogenic properties. Here, we systematically profiled the factors that regulate protein stability of wild-type and mutant p53 using marker-based genome-wide CRISPR screens. Most regulators of wild-type p53 also regulate p53 mutants, except for p53 R337H regulators, which are largely private to this mutant. Mechanistically, FBXO42 emerged as a positive regulator for a subset of p53 mutants, working with CCDC6 to control USP28-mediated mutant p53 stabilization. Additionally, C16orf72/HAPSTR1 negatively regulates both wild-type p53 and all tested mutants. C16orf72/HAPSTR1 is commonly amplified in breast cancer, and its overexpression reduces p53 levels in mouse mammary epithelium leading to accelerated breast cancer. This study offers a network perspective on p53 stability regulation, potentially guiding strategies to reinforce wild-type p53 or target mutant p53 in cancer.


Assuntos
Mutação , Estabilidade Proteica , Proteína Supressora de Tumor p53 , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Animais , Humanos , Camundongos , Feminino , Sistemas CRISPR-Cas , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Regulação Neoplásica da Expressão Gênica , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas
3.
Ann Diagn Pathol ; 69: 152249, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38150865

RESUMO

INTRODUCTION: Next-generation sequencing (NGS) of Formalin-Fixed and Paraffin-Embedded (FFPE) specimens is routine in precision oncology practice. However, results are not always conclusive, and it is important to identify which factors may influence FFPE tumor sequencing success. MATERIALS AND METHODS: Here, we evaluated the influence of pre-analytical factors on 705 samples of non-small cell lung cancer specimens that underwent NGS testing. Factors such as tumor site, tumor cell percentage, fragment size, primary tumor or metastasis, presence of necrosis, DNA purity, DNA concentration, sample origin and year of testing. RESULTS: The overall NGS success rate was 84.9 % (n = 599). Bone site specimens had a very low success rate (42.1 %), differing from lung samples (79.8 %) (P < 0.05). Samples with tumor percentages <5 % (success rate of 44.4 %) represented 14.1 % of failed sequencings. Moreover, samples with tumor percentages >10 %-20 % (82 %) did not differ from those with >30 % (88.9 %) on sequencing outcomes (P = 0.086). Specimens that provided DNA concentrations >2.0 ng/uL, 1.0-2.0 ng/uL, 0.5-1.0 ng/uL and <0.5 ng/uL had success rates of 92 %, 77.1 %, 61.3 % and 20.4 %, respectively. Small fragments (≤0.2 cm2) had a success rate of 74.7 % and were more prevalent in the unsuccessful group (P < 0.05). CONCLUSIONS: Our results suggest that tumor percentage, fragment size, decalcified bone specimens, and DNA concentration are potential modifiers of NGS success rates. Interestingly, specimens with tumor percentages between 10 % and 20 % have the same sequencing outcome than specimens with >30 %. These results can strengthen the understanding of factors that lead to NGS success variability.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Inclusão em Parafina , Medicina de Precisão , DNA , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Formaldeído , Mutação
4.
Genet Mol Biol ; 46(3 Suppl 1): e20230132, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38373162

RESUMO

Tuberous Sclerosis Complex (TSC) is caused by loss of function germline variants in the TSC1 or TSC2 tumor suppressor genes. Genetic testing for the detection of pathogenic variants in either TSC1 or TSC2 was implemented as a diagnostic criterion for TSC. However, TSC molecular diagnosis can be challenging due to the absence of variant hotspots and the high number of variants described. This review aimed to perform an overview of TSC1/2 variants submitted in the ClinVar database. Variants of uncertain significance (VUS), missense and single nucleotide variants were the most frequent in clinical significance (37-40%), molecular consequence (37%-39%) and variation type (82%-83%) categories in ClinVar in TSC1 and TSC2 variants, respectively. Frameshift and nonsense VUS have potential for pathogenic reclassification if further functional and segregation studies were performed. Indeed, there were few functional assays deposited in the database and literature. In addition, we did not observe hotspots for variation and many variants presented conflicting submissions regarding clinical significance. This study underscored the importance of disseminating molecular diagnostic results in a public database to render the information largely accessible and promote accurate diagnosis. We encourage the performance of functional studies evaluating the pathogenicity of TSC1/2 variants.

5.
Genet Mol Biol ; 46(3 Suppl 1): e20230133, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38252059

RESUMO

The TP53 3'UTR variant rs78378222 A>C has been detected in different tumor types as a somatic alteration that reduces p53 expression through modification of polyadenylation and miRNA regulation. Its prevalence is not yet known in all tumors. Herein, we examine tumor tissue prevalence of rs7837822 in Brazilian cohorts of patients from south and southeast regions diagnosed with lung adenocarcinoma (LUAD, n=586), sarcoma (SARC, n=188) and uterine leiomyoma (ULM, n=41). The minor allele (C) was identified in heterozygosity in 6/586 LUAD tumors (prevalence = 1.02 %) and none of the SARC and ULM samples. Additionally, next generation sequencing analysis revealed that all variant-positive tumors (n=4) with sample availability had additional pathogenic or likely pathogenic somatic variants in the TP53 coding regions. Among them, 3/4 (75 %) had the same pathogenic or likely pathogenic sequence variant (allele frequency <0.05 in tumor DNA) namely c.751A>C (p.Ile251Leu). Our results indicate a low somatic prevalence of rs78378222 in LUAD, ULM and SARC tumors from Brazilian patients, which suggests that no further analysis of this variant in the specific studied regions of Brazil is warranted. However, these findings should not exclude tumor molecular testing of this TP53 3'UTR functional variant for different populations.

6.
An Acad Bras Cienc ; 95(3): e20220801, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37851747

RESUMO

The coronavirus disease 2019 (COVID-19) mortality rates varied among the states of Brazil during the course of the pandemics. The human leukocyte antigen (HLA) is a critical component of the antigen presentation pathway. Individuals with different HLA genotypes may trigger different immune responses against pathogens, which could culminate in different COVID-19 responses. HLA genotypes are variable, especially in the highly admixed Brazilian population. In this ecological study, we aimed to investigate the correlation between HLA haplotypes and the different regional distribution of COVID-19 mortality in Brazil. HLA data was obtained from 4,148,713 individuals registered in The Brazilian Voluntary Bone Marrow Donors Registry. COVID-19 data was retrieved from epidemiological bulletins issued by State Health Secretariats via Brazil's Ministry of Health from February/2020 to July/2022. We found a positive significant correlation between the HLA-A*01~B*08~DRB1*03 haplotype and COVID-19 mortality rates when we analyzed data from 26 states and the Federal District. This result indicates that the HLA-A*01~B*08~DRB1*03 haplotype may represent an additional risk factor for dying due to COVID-19. This haplotype should be further studied in other populations for a better understanding of the variation in COVID-19 outcomes across the world.


Assuntos
Medula Óssea , COVID-19 , Humanos , Haplótipos , Brasil/epidemiologia , Frequência do Gene , Antígenos HLA-B/genética , COVID-19/genética , Cadeias HLA-DRB1/genética , Alelos , Antígenos HLA/genética , Antígenos HLA-A/genética
7.
Exp Eye Res ; 224: 109211, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35985532

RESUMO

Retinoblastoma is a rare childhood tumor caused by the inactivation of both copies of the RB1 gene. Early diagnosis and identification of heritable RB1 mutation carriers can improve the disease outcome and management via genetic counseling. We used the Multiplex Ligation-dependent Probe Amplification (MLPA) method to analyze the RB1 gene and flanking regions in blood samples from 159 retinoblastoma patients previously negative for RB1 point mutations via Sanger sequencing. We detected a wide spectrum of germline chromosomal alterations, ranging from partial loss or duplication of RB1 to large deletions spanning RB1 and adjacent genes. Mutations were validated via karyotyping, fluorescent in situ hybridization (FISH), SNP-arrays (Single Nucleotide Polymorphism-arrays) and/or quantitative relative real-time PCR. Patients with leukocoria as a presenting symptom showed reduced death rate (p = 0.013) and this sign occurred more frequently among carriers of two breakpoints within RB1 (p = 0.05). All unilateral cases presented both breakpoints outside of RB1 (p = 0.0075). Patients with one breakpoint within RB1 were diagnosed at earlier ages (p = 0.017). Our findings characterize the mutational spectrum of a Brazilian cohort of retinoblastoma patients and point to a possible relationship between the mutation breakpoint location and tumor outcome, contributing to a better prospect of the genotype/phenotype correlation and adding to the wide diversity of germline mutations involving RB1 and adjacent regions in retinoblastoma.


Assuntos
Neoplasias da Retina , Retinoblastoma , Humanos , Retinoblastoma/diagnóstico , Retinoblastoma/genética , Retinoblastoma/patologia , Hibridização in Situ Fluorescente , Brasil/epidemiologia , Genes do Retinoblastoma/genética , Mutação , Neoplasias da Retina/patologia , Análise Mutacional de DNA
8.
J Surg Oncol ; 126(1): 10-19, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35689574

RESUMO

BACKGROUND: Risk-reducing operations are an important part of the management of hereditary predisposition to cancer. In selected cases, they can considerably reduce the morbidity and mortality associated with cancer in this population. OBJECTIVES: The Brazilian Society of Surgical Oncology (BSSO) developed this guideline to establish national benchmarks for cancer risk-reducing operations. METHODS: The guideline was prepared from May to December 2021 by a multidisciplinary team of experts to discuss the surgical management of cancer predisposition syndromes. Fourteen questions were defined and assigned to expert groups that reviewed the literature and drafted preliminary recommendations. Following a review by the coordinators and a second review by all participants, the groups made final adjustments, classified the level of evidence, and voted on the recommendations. RESULTS: For all questions including risk-reduction bilateral salpingo-oophorectomy, hysterectomy, and mastectomy, major agreement was achieved by the participants, always using accessible alternatives. CONCLUSION: This and its accompanying article represent the first guideline in cancer risk reduction surgery developed by the BSSO, and it should serve as an important reference for the management of families with cancer predisposition.


Assuntos
Neoplasias da Mama , Ginecologia , Neoplasias Ovarianas , Oncologia Cirúrgica , Brasil/epidemiologia , Neoplasias da Mama/genética , Neoplasias da Mama/prevenção & controle , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mastectomia , Neoplasias Ovarianas/cirurgia
9.
J Surg Oncol ; 126(1): 20-27, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35689578

RESUMO

BACKGROUND: Risk-reducing operations are an important part of the management of hereditary predisposition to cancer. In selected cases, they can considerably reduce the morbidity and mortality associated with cancer in this population. OBJECTIVES: The Brazilian Society of Surgical Oncology (BSSO) developed this guideline to establish national benchmarks for cancer risk-reducing operations. METHODS: The guideline was prepared from May to December 2021 by a multidisciplinary team of experts to discuss the surgical management of cancer predisposition syndromes. Eleven questions were defined and assigned to expert groups that reviewed the literature and drafted preliminary recommendations. Following a review by the coordinators and a second review by all participants, the groups made final adjustments, classified the level of evidence, and voted on the recommendations. RESULTS: For all questions including risk-reducing colectomy, gastrectomy, and thyroidectomy, a major agreement was achieved by the participants, always using accessible alternatives. CONCLUSION: This and its accompanying article represent the first guideline in cancer risk reduction surgery developed by the BSSO and it should serve as an important reference for the management of families with cancer predisposition.


Assuntos
Neoplasias , Oncologia Cirúrgica , Brasil/epidemiologia , Humanos , Glândula Tireoide
10.
Eur J Clin Microbiol Infect Dis ; 40(4): 889-892, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33063233

RESUMO

This study has aimed to evaluate the use pool of samples as a strategy to optimize the diagnostic of SARS-CoV-2 by RT-qPCR. A total of 220 naso/orofaryngeal swab samples were collected and tested using two different protocols of sample pooling. Results from protocol A were identical with the individual results. However, for results from protocol B, reduced agreement (91%) was observed in relation to individual testing. Inconsistencies observed were related to RT-qPCR results with higher cycle thresholds. These results suggest that pooling of samples before RNA extraction is preferable in terms of diagnostic for SARS-CoV-2.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Manejo de Espécimes/métodos , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2
11.
Genet Mol Biol ; 44(2): e20200014, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33821877

RESUMO

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder caused by germline mutations in TSC1 or TSC2 genes, which leads to the hyperactivation of the mTORC1 pathway, an important negative regulator of autophagy. This leads to the development of hamartomas in multiple organs. The variability in symptoms presents a challenge for the development of completely effective treatments for TSC. One option is the treatment with mTORC1 inhibitors, which are targeted to block cell growth and restore autophagy. However, the therapeutic effect of rapamycin seems to be more efficient in the early stages of hamartoma development, an effect that seems to be associated with the paradoxical role of autophagy in tumor establishment. Under normal conditions, autophagy is directly inhibited by mTORC1. In situations of bioenergetics stress, mTORC1 releases the Ulk1 complex and initiates the autophagy process. In this way, autophagy promotes the survival of established tumors by supplying metabolic precursors during nutrient deprivation; paradoxically, excessive autophagy has been associated with cell death in some situations. In spite of its paradoxical role, autophagy is an alternative therapeutic strategy that could be explored in TSC. This review compiles the findings related to autophagy and the new therapeutic strategies targeting this pathway in TSC.

12.
Genet Mol Biol ; 44(4): e20200475, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34609442

RESUMO

Tuberous sclerosis complex (TSC) is an autosomal dominant cancer predisposition disorder caused by heterozygous mutations in TSC1 or TSC2 genes and characterized by mTORC1 hyperactivation. TSC-associated tumors develop after loss of heterozygosity mutations and their treatment involves the use of mTORC1 inhibitors. We aimed to evaluate cellular processes regulated by mTORC1 in TSC cells with different mutations before tumor development. Flow cytometry analyses were performed to evaluate cell viability, cell cycle and autophagy in non-tumor primary TSC cells with different heterozygous mutations and in control cells without TSC mutations, before and after treatment with rapamycin (mTORC1 inhibitor). We did not observe differences in cell viability and cell cycle between the cell groups. However, autophagy was reduced in mutated cells. After rapamycin treatment, mutated cells showed a significant increase in the autophagy process (p=0.039). We did not observe differences between cells with distinct TSC mutations. Our main finding is the alteration of autophagy in non-tumor TSC cells. Previous studies in literature found autophagy alterations in tumor TSC cells or knock-out animal models. We showed that autophagy could be an important mechanism that leads to TSC tumor formation in the haploinsufficiency state. This result could guide future studies in this field.

13.
Breast Cancer Res ; 22(1): 108, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33087180

RESUMO

BACKGROUND: The BRCA1 c.3331_3334delCAAG founder mutation has been reported in hereditary breast and ovarian cancer families from multiple Hispanic groups. We aimed to evaluate BRCA1 c.3331_3334delCAAG haplotype diversity in cases of European, African, and Latin American ancestry. METHODS: BC mutation carrier cases from Colombia (n = 32), Spain (n = 13), Portugal (n = 2), Chile (n = 10), Africa (n = 1), and Brazil (n = 2) were genotyped with the genome-wide single nucleotide polymorphism (SNP) arrays to evaluate haplotype diversity around BRCA1 c.3331_3334delCAAG. Additional Portuguese (n = 13) and Brazilian (n = 18) BC mutation carriers were genotyped for 15 informative SNPs surrounding BRCA1. Data were phased using SHAPEIT2, and identical by descent regions were determined using BEAGLE and GERMLINE. DMLE+ was used to date the mutation in Colombia and Iberia. RESULTS: The haplotype reconstruction revealed a shared 264.4-kb region among carriers from all six countries. The estimated mutation age was ~ 100 generations in Iberia and that it was introduced to South America early during the European colonization period. CONCLUSIONS: Our results suggest that this mutation originated in Iberia and later introduced to Colombia and South America at the time of Spanish colonization during the early 1500s. We also found that the Colombian mutation carriers had higher European ancestry, at the BRCA1 gene harboring chromosome 17, than controls, which further supported the European origin of the mutation. Understanding founder mutations in diverse populations has implications in implementing cost-effective, ancestry-informed screening.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Haplótipos , Polimorfismo de Nucleotídeo Único , África/epidemiologia , Brasil/epidemiologia , Chile/epidemiologia , Cromossomos Humanos Par 17/genética , Colômbia/epidemiologia , Feminino , Efeito Fundador , Estudo de Associação Genômica Ampla/métodos , Humanos , Portugal/epidemiologia , Espanha/epidemiologia
14.
BMC Cancer ; 20(1): 1069, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33167923

RESUMO

BACKGROUND: Melanoma is the most aggressive type of skin cancer and is associated with environmental and genetic risk factors. It originates in melanocytes, the pigment-producing cells. Single nucleotide polymorphisms (SNPs) in pigmentation genes have been described in melanoma risk modulation, but knowledge in the field is still limited. METHODS: In a case-control approach (107 cases and 119 controls), we investigated the effect of four pigmentation gene SNPs (TYR rs1126809, HERC2 rs1129038, SLC24A5 rs1426654, and SLC45A2 rs16891982) on melanoma risk in individuals from southern Brazil using a multivariate logistic regression model and multifactor dimensionality reduction (MDR) analysis. RESULTS: Two SNPs were associated with an increased risk of melanoma in a dominant model: rs1129038AA and rs1426654AA [OR = 2.094 (95% CI: 1.106-3.966), P = 2.3 10- 2 and OR = 7.126 (95% CI: 1.873-27.110), P = 4.0 10- 3, respectively]. SNP rs16891982CC was associated with a lower risk to melanoma development in a log-additive model when the allele C was inherited [OR = 0.081 (95% CI: 0.008-0.782), P = 3 10- 2]. In addition, MDR analysis showed that the combination of the rs1426654AA and rs16891982GG genotypes was associated with a higher risk for melanoma (P = 3 10- 3), with a redundant effect. CONCLUSIONS: These results contribute to the current knowledge and indicate that epistatic interaction of these SNPs, with an additive or correlational effect, may be involved in modulating the risk of melanoma in individuals from a geographic region with a high incidence of the disease.


Assuntos
Biomarcadores Tumorais/genética , Melanoma/epidemiologia , Polimorfismo de Nucleotídeo Único , Neoplasias Cutâneas/epidemiologia , Pigmentação da Pele/genética , Antígenos de Neoplasias/genética , Antiporters/genética , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Seguimentos , Genótipo , Humanos , Incidência , Masculino , Melanoma/genética , Melanoma/patologia , Proteínas de Membrana Transportadoras/genética , Pessoa de Meia-Idade , Monofenol Mono-Oxigenase/genética , Prognóstico , Fatores de Risco , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Ubiquitina-Proteína Ligases/genética
15.
Psychooncology ; 29(4): 681-687, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31984583

RESUMO

OBJECTIVE: There is a lack of information describing Brazilian women at risk of hereditary breast and ovarian cancer syndrome (HBOC) who undergo genetic cancer risk assessment (GCRA). This study aims to characterize the psychosocial profile of women at risk for HBOC at their first GCRA to obtain an overview of their families' profiles and the challenges of the oncogenetics setting. METHODS: This was a cross-sectional study in which interviews were conducted with 83 cancer-affected women at their first GRCA appointment after the pedigree draw. Tools to evaluate psychological outcomes were applied. The pedigree genogram and ecomap were constructed and analyzed with content analysis using the "life course perspective" theory. RESULTS: Individuals perceived their breast/ovarian cancer risk to be equal to that of the general population, although they were highly concerned about developing cancer. No evidence of anxiety or depressive symptoms was identified. Participants used the coping strategy of searching for religiosity. The genograms and ecomaps resulted in five major themes: support and social support; attitudes, feelings and emotions; cancer causes; communication; and relationships with relatives. Individuals between 20-29 years of age and those with no family history of cancer tended not to communicate with relatives, which may indicate future problems in the GCRA process regarding genetic testing. CONCLUSIONS: This study demonstrated that knowing the families who undergo the GCRA process can help professionals provide more individualized and thorough attention during GCRA and genetic testing, which results in better follow-up and prevention strategies.


Assuntos
Adaptação Psicológica , Testes Genéticos , Síndrome Hereditária de Câncer de Mama e Ovário/psicologia , Medição de Risco , Apoio Social , Adulto , Brasil , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem
16.
BMC Gastroenterol ; 20(1): 394, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33225890

RESUMO

BACKGROUND: Tuberous Sclerosis Complex (TSC) is a complex and heterogeneous genetic disease that has well-established clinical diagnostic criteria. These criteria do not include gastrointestinal tumors. CASE PRESENTATION: We report a 45-year-old patient with a clinical and molecular diagnosis of TSC and a family history of cancer, presenting two rare associated findings: gastrointestinal polyposis and pancreatic neuroendocrine tumor. This patient was subjected to a genetic test with 80 cancer predisposing genes. The genetic panel revealed the presence of a large pathogenic deletion in the TSC2 gene, covering exons 2 to 16 and including the initiation codon. No changes were identified in the colorectal cancer and colorectal polyposis genes. DISCUSSION AND CONCLUSIONS: We describe a case of TSC that presented tumors of the gastro intestinal tract that are commonly unrelated to the disease. The patient described here emphasizes the importance of considering polyposis of the gastrointestinal tract and low grade neuroendocrine tumor as part of the TSC syndromic phenotype.


Assuntos
Angiomiolipoma , Neoplasias Renais , Esclerose Tuberosa , Feminino , Trato Gastrointestinal , Humanos , Pessoa de Meia-Idade , Mutação , Esclerose Tuberosa/complicações , Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética
17.
Genet Mol Biol ; 43(2): e20190097, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32325485

RESUMO

In Brazil, the population in general has little knowledge about genetic risks, as well as regarding the role and importance of the Cancer Genetic Counseling (CGC). The goal of this study was to evaluate cancer-related worry and cancer risk perception during CGC sessions in Brazilian women at-risk for hereditary breast cancer. This study was performed in 264 individuals seeking CGC for hereditary breast cancer. Both cancer-affected and unaffected individuals were included. As results, individuals with and without cancer reported different motivations for seeking CGC and undergoing genetic testing. A correlation was observed between age at the first CGC session and age at which the closest relative was diagnosed with cancer. Multivariate analysis showed that educational level, cancer risk discussion within the family, and number of deaths by cancer among first-degree relatives influenced positively the cancer risk perception. In conclusion, the results of this study indicate that cancer-related worry and cancer risk perception are significant aspects of morbidity in individuals seeking CGC, whether they are cancer-affected or unaffected. CGC has an important role in health education and cancer prevention for its potential of promoting an accurate perception of the risk.

18.
Genet Mol Biol ; 43(2): e20190072, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32453342

RESUMO

Specific pathogenic mutations associated with breast cancer development can vary between ethnical groups. One example is BRCA1 c.5266dupC that was first described as a founder mutation in the Ashkenazi Jewish population, but was later also found in other populations. In Brazil, this mutation corresponds to 20% of pathogenic BRCA1 variants reported. Our objective was to investigate the haplotype component of a group of Brazilian families who inherited c.5266dupC in the BRCA1 gene and to verify the ancestry contribution from European, African, and Amerindian origins. Fourteen probands carrying c.5266dupC and 16 relatives (carriers and non-carriers) were investigated. The same haplotype was observed segregating within all the families analyzed, revealing no recombinants in a region of 0.68 Mb. Ancestry analysis demonstrated that the European component was predominant among probands. The BRCA1 c.5266dupC analysis indicates that there was a founder effect in the Brazilian population.

19.
Genet Mol Biol ; 42(1 suppl 1): 215-231, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31067289

RESUMO

Germline mutations in BRCA1 and BRCA2 (BRCA) genes confer high risk of developing cancer, especially breast and ovarian tumors. Since the cloning of these tumor suppressor genes over two decades ago, a significant amount of research has been done. Most recently, monoallelic loss-of-function mutations in PALB2 have also been shown to increase the risk of breast cancer. The identification of BRCA1, BRCA2 and PALB2 as proteins involved in DNA double-strand break repair by homologous recombination and of the impact of complete loss of BRCA1 or BRCA2 within tumors have allowed the development of novel therapeutic approaches for patients with germline or somatic mutations in said genes. Despite the advances, especially in the clinical use of PARP inhibitors, key gaps remain. Now, new roles for BRCA1 and BRCA2 are emerging and old concepts, such as the classical two-hit hypothesis for tumor suppression, have been questioned, at least for some BRCA functions. Here aspects regarding cancer predisposition, cellular functions, histological and genomic findings in BRCA and PALB2-related tumors will be presented, in addition to an up-to-date review of the evolution and challenges in the development and clinical use of PARP inhibitors.

20.
Genet Mol Biol ; 42(1 suppl 1): 232-237, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31170278

RESUMO

Breast cancer (BC) risk assessment models base their estimations on different aspects of a woman's personal and familial history. The Gail and Tyrer-Cuzick models are the most commonly used, and BC risks assigned by them vary considerably especially concerning familial history. In this study, our aim was to compare the Gail and Tyrer-Cuzick models after initial screening for familial history of cancer in primary care using the FHS-7 questionnaire. We compared 846 unrelated women with at least one positive answer to any of the seven FHS-7 questions (positive group) and 892 unrelated women that answered negatively (negative group). Concordance between BC risk estimates was compared by Bland-Altman graphics. Mean BC risk estimates were higher using the Tyrer-Cuzick Model in women from the positive group, while women from the negative group had higher BC risk estimates using the Gail model. With increasing estimates, discordance also increased, mainly in the FHS-7 positive group. Our results show that in women with a familial history of cancer, the Gail model underestimates risk and the Tyrer-Cuzick seems to be more appropriate. FHS-7 can be a useful tool for the identification of women with higher breast cancer risks in the primary care setting.

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