Rev Assoc Med Bras (1992)
June 2024
MUTYH encodes a glycosylase involved in the base excision repair of DNA. Biallelic pathogenic germline variants in MUTYH cause an autosomal recessive condition known as MUTYH-associated adenomatous polyposis and consequently increase the risk of colorectal cancer. However, reports of increased cancer risk in individuals carrying only one defective MUTYH allele are controversial and based on studies involving few individuals.
View Article and Find Full Text PDFPurpose Of Review: Germline pathogenic TP53 mutation may predispose to multiple cancers but penetrance and cancer patterns remain incompletely documented. We have analyzed international agency for research on cancer TP53 database to reevaluate age and variant-dependent tumor patterns.
Recent Findings: Genome-wide studies suggest that germline variants are more frequent than estimated prevalence of Li-Fraumeni syndrome (LFS), suggesting that many carriers of potentially pathogenic mutations may not develop the syndrome.
Lynch syndrome (LS) is an autosomal dominant disorder, with high penetrance that affects approximately 3% of the cases of colorectal cancer. Affected individuals inherit germline mutations in genes responsible for DNA mismatch repair, mainly at MSH2, MLH1, MSH6 and PMS2. The molecular screening of these individuals is frequently costly and time consuming due to the large size of these genes.
View Article and Find Full Text PDFPurpose: Although the link between mutant TP53 and human cancer is unequivocal, a significant knowledge gap exists in clinically actionable molecular targets in Li-Fraumeni syndrome (LFS), a highly penetrant cancer predisposition syndrome associated with germline mutations in TP53. This study surveyed the epigenome to identify functionally and clinically relevant novel genes implicated in LFS.
Patients And Methods: We performed genome-wide methylation analyses of peripheral blood leukocyte DNA in germline TP53 mutation carriers (n = 72) and individuals with TP53 wild type in whom histologically comparable malignancies developed (n = 111).
Gardner's syndrome (GS) is a genetic disorder characterised by intestinal polyps, multiple osteomas, and soft-tissue tumours. Dentists play an important role in the syndrome diagnosis considering that craniomaxillofacial osteomas are a major criteria for Gardner's syndrome diagnosis. This study aimed to describe the main stomatological manifestation of GS and the importance of dentists in its diagnosis.
View Article and Find Full Text PDFBackground: Interval debulking surgery (IDS) is an option for treating patients with advanced ovarian carcinoma. Two randomized trials have shown similar survival rates for primary debulking surgery (PDS) and IDS. One of the concerns with IDS is the potentially higher risk of inducing platinum resistance when treating patients with greater disease volume.
View Article and Find Full Text PDFPurpose: To evaluate the effectiveness of (18)F-Fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG-PET/CT) for detecting early cancer in carriers of germline TP53 mutation, the genetic defect underlying Li-Fraumeni and related syndromes, which predisposes to many forms of cancer throughout life.
Patients And Methods: A total of 30 adult patients from six families with germline TP53 mutations were recruited. These patients did not have a diagnosis of cancer in the 24 months preceding the study.
Aberrant DNA methylation pattern is a well-known epigenetic marker of cancer cells. Recently, aberrant methylation was also reported in the peripheral blood of cancer patients and it could potentially serve as a biomarker for cancer risk. We investigated the methylation pattern of LINE-1 and other repetitive DNA elements in peripheral blood of cutaneous melanoma patients in order to search for an association with clinical characteristics.
View Article and Find Full Text PDFMelanoma is a highly aggressive cancer, accounting for up to 75% of skin cancer deaths. A small proportion of melanoma cases can be ascribed to the presence of highly penetrant germline mutations, and approximately 40% of hereditary melanoma cases are caused by CDKN2A mutations. The current study sought to investigate whether the presence of germline CDKN2A mutations or the occurrence of cutaneous melanoma would result in constitutive genome-wide DNA methylation changes.
View Article and Find Full Text PDFApproximately 10 % of all cutaneous melanoma cases occur in a familial context. The major susceptibility gene for familial melanoma is CDKN2A. In Latin America, genetic studies investigating melanoma predisposition are scarce.
View Article and Find Full Text PDFOrphanet J Rare Dis
April 2013
Background: Patients with multiple colorectal adenomas are currently screened for germline mutations in two genes, APC and MUTYH. APC-mutated patients present classic or attenuated familial adenomatous polyposis (FAP/AFAP), while patients carrying biallelic MUTYH mutations exhibit MUTYH-associated polyposis (MAP). The spectrum of mutations as well as the genotype-phenotype correlations in polyposis syndromes present clinical impact and can be population specific, making important to obtain genetic and clinical data from different populations.
View Article and Find Full Text PDFPurpose: The article aims to introduce nurses to how genetics-genomics is currently integrated into cancer care from prevention to treatment and influencing oncology nursing practice.
Organizing Construct: An overview of genetics-genomics is described as it relates to cancer etiology, hereditary cancer syndromes, epigenetics factors, and management of care considerations.
Methods: Peer-reviewed literature and expert professional guidelines were reviewed to address concepts of genetics-genomics in cancer care.
Background: Li-Fraumeni (LFS) and Li-Fraumeni-like (LFL) syndromes are associated to germline TP53 mutations, and are characterized by the development of central nervous system tumors, sarcomas, adrenocortical carcinomas, and other early-onset tumors. Due to the high frequency of breast cancer in LFS/LFL families, these syndromes clinically overlap with hereditary breast cancer (HBC). Germline point mutations in BRCA1, BRCA2, and TP53 genes are associated with high risk of breast cancer.
View Article and Find Full Text PDFIntroduction: Genetic factors predisposing individuals to cancer remain elusive in the majority of patients with a familial or clinical history suggestive of hereditary breast cancer. Germline DNA copy number variation (CNV) has recently been implicated in predisposition to cancers such as neuroblastomas as well as prostate and colorectal cancer. We evaluated the role of germline CNVs in breast cancer susceptibility, in particular those with low population frequencies (rare CNVs), which are more likely to cause disease.
View Article and Find Full Text PDFBackground: Gastric adenocarcinoma is rare in children and adolescents, with about 17 cases under age 21 in the world's literature. We report a case of invasive well-differentiated metastatic gastric cancer in a Brazilian 12-year-old boy without documented familial history of cancer.
Case Presentation: The patient, diagnosed with metastatic disease, died seven months after surgery.
DNA copy-number variations (CNVs) underlie many neuropsychiatric conditions, but they have been less studied in cancer. We report the association of a 17p13.1 CNV, childhood-onset developmental delay (DD), and cancer.
View Article and Find Full Text PDFDue to patterns of migration, selection, and population expansion, founder effects are common among humans. In Southern Brazil, a recurrent TP53 mutation, p.R337H, is detected in families with cancer predisposition.
View Article and Find Full Text PDFThe unusually high population frequency of a germline TP53 mutation (R337H) predisposing to early cancer has led to mass newborn testing for this mutation in the State of Paraná, southern Brazil. Newborn screening for inherited cancer risk is complex and controversial. In this paper, we discuss the justifications for this screening by considering the medical and scientific evidence for this mutation.
View Article and Find Full Text PDFGermline TP53 mutations predispose to a rare familial cancer syndrome, the Li-Fraumeni Syndrome (LFS), characterized by the early onset of multiple cancers including childhood adrenocortical carcinomas, sarcomas and brain tumors, and breast and colon cancer in young adults. An identical germline mutation at codon 337 in TP53 (R337H) has been shown to be causally related to an increased risk of multiple cancers in unrelated subjects with familial cancer risk in Southern Brazil. Here we have assessed the prevalence of R337H in 750 healthy women participating in a community-based breast cancer screening program in the area of Porto Alegre.
View Article and Find Full Text PDFA TP53 germline mutation, R337H, has been previously described in children from southern Brazil with adrenocortical tumours but no documented familial history of other cancers. Here, we have screened for TP53 mutation 45 Brazilian unrelated individuals with family histories fulfilling the clinical definitions of Li-Fraumeni (LFS) or Li-Fraumeni-like (LFL) syndromes. Mutations were found in 13 patients (28.
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