Germline genetic testing with hereditary cancer gene panels can identify women at increased risk of breast cancer. However, those at increased risk of triple-negative (estrogen receptor-negative, ...progesterone receptor-negative, human epidermal growth factor receptor-negative) breast cancer (TNBC) cannot be identified because predisposition genes for TNBC, other than BRCA1, have not been established. The aim of this study was to define the cancer panel genes associated with increased risk of TNBC.
Multigene panel testing for 21 genes in 8753 TNBC patients was performed by a clinical testing laboratory, and testing for 17 genes in 2148 patients was conducted by a Triple Negative Breast Cancer Consortium (TNBCC) of research studies. Associations between deleterious mutations in cancer predisposition genes and TNBC were evaluated using results from TNBC patients and reference controls.
Germline pathogenic variants in BARD1, BRCA1, BRCA2, PALB2, and RAD51D were associated with high risk (odds ratio > 5.0) of TNBC and greater than 20% lifetime risk for overall breast cancer among Caucasians. Pathogenic variants in BRIP1, RAD51C, and TP53 were associated with moderate risk (odds ratio > 2) of TNBC. Similar trends were observed for the African American population. Pathogenic variants in these TNBC genes were detected in 12.0% (3.7% non-BRCA1/2) of all participants.
Multigene hereditary cancer panel testing can identify women with elevated risk of TNBC due to mutations in BARD1, BRCA1, BRCA2, PALB2, and RAD51D. These women can potentially benefit from improved screening, risk management, and cancer prevention strategies. Patients with mutations may also benefit from specific targeted therapeutic strategies.
PALB2 loss-of-function variants play an important role in breast, pancreatic and possibly, ovarian and gastric cancer susceptibility. Their frequency can be influenced by founder effects, already ...described in some populations. Herein, we have assessed the possible founder effect of PALB2 c.2257C>T (p.Arg753*) truncating variant among Greek breast cancer patients, while investigating possible correlations with cancer diagnoses. Following a lead deriving from a background study of highly selected Greek breast cancer patients, a total of 2496 breast and 697 ovarian cancer patients were directly genotyped for the PALB2 c.2257C>T truncating variant. Consequently, haplotype analysis was conducted on identified carriers, using seven microsatellite markers. The prevalence of the PALB2 variant was 0.24% (6/2496) and 0.14% (1/697) among breast and ovarian cases, respectively. Family history seems to be an important factor for the variant identification, although not reaching statistical significance. Microsatellite analysis on 12 carriers revealed a common shared haplotype, spanning a chromosomal region of ~1.2 Mb; the variant was possibly introduced in the Greek population ~1600 years ago. The variant confers high breast cancer risk, as illustrated by comparison with publicly available control groups. Genetic testing for PALB2, especially for the Greek founder c.2257C>T truncating variant, should be seriously considered in Greek breast cancer cases, since such findings could assist appropriate clinical management for the patients and their families.
Early-onset breast cancer constitutes a major criterion for genetic testing referral. Nevertheless, studies focusing on breast cancer patients (≤30 years) are limited. We investigated the ...contribution and spectrum of known breast-cancer-associated genes in 267 Greek women with breast cancer ≤30 years while monitoring their clinicopathological characteristics and outcomes. In this cohort, a significant proportion (39.7%) carried germline pathogenic variants (PVs) distributed in 8 genes. The majority, namely 36.7%, involved BRCA1, TP53, and BRCA2. PVs in BRCA1 were the most prevalent (28.1%), followed by TP53 (4.5%) and BRCA2 (4.1%) PVs. The contribution of PVs in CHEK2, ATM, PALB2, PTEN, and RAD51C was limited to 3%. In the patient group ≤26 years, TP53 PVs were significantly higher compared to the group 26–30 years (p = 0.0023). A total of 74.8% of TP53 carriers did not report a family history of cancer. Carriers of PVs receiving neoadjuvant chemotherapy showed an improved event-free survival (p < 0.0001) compared to non-carriers. Overall, many women with early-onset breast cancer carry clinically actionable variants, mainly in the BRCA1/2 and TP53 genes. The inclusion of timely testing of TP53 in these patients provides essential information for appropriate clinical management. This is important for countries where reimbursement involves the cost of genetic analysis of BRCA1/2 only.
Tuberous sclerosis complex (TSC) is a rare autosomal dominant disorder causing benign tumors in the brain and other vital organs. The genes implicated in disease development are TSC1 and TSC2. Here, ...we have performed mutational analysis followed by a genotype-phenotype correlation study based on the clinical characteristics of the affected individuals. Twenty unrelated probands or families from Greece have been analyzed, of whom 13 had definite TSC, whereas another 7 had a possible TSC diagnosis. Using direct sequencing, we have identified pathogenic mutations in 13 patients/families (6 in TSC1 and 7 in TSC2), 5 of which were novel. The mutation identification rate for patients with definite TSC was 85%, but only 29% for the ones with a possible TSC diagnosis. Multiplex ligation-dependent probe amplification (MLPA) did not reveal any genomic rearrangements in TSC1 and TSC2 in the samples with no mutations identified. In general, TSC2 disease was more severe than TSC1, with more subependymal giant cell astrocytomas and angiomyolipomas, higher incidence of pharmacoresistant epileptic seizures, and more severe neuropsychiatric disorders. To our knowledge, this is the first comprehensive TSC1 and TSC2 mutational analysis carried out in TSC patients in Greece.
RAD51D gene's protein product is known to be involved in the DNA repair mechanism by homologous recombination. RAD51D germline mutations have been recently associated with ovarian and breast cancer ...(OC and BC, respectively) predisposition. Our aim was to evaluate the frequency of hereditary RAD51D mutations in Greek patients. To address this, we have screened for RAD51D germline mutations 609 BRCA1- and BRCA2-negative patients diagnosed with OC, unselected for age or family history, and 569 BC patients diagnosed under 55 years and with an additional relative with BC or OC. We identified four pathogenic mutations in four unrelated individuals with family history of BC and/or OC. Three of the RAD51D carriers had developed BC, while the other one was an OC patient, thus accounting for a mutation frequency of 0.16% in the OC cohort and 0.53% in the BC cohort. One of the detected mutations is novel (c.738 + 1G > A), whereas the rest had been detected previously (p.Gln151Ter, p.Arg186Ter, and p.Arg300Ter). It is noteworthy that the 4 carrier families had 13 BC cases and only 4 OC cases. Our data support that RAD51D should be implemented into the comprehensive multigene panel, as mutation carriers may benefit from the administration of PARP inhibitors.
Germline CHEK2 mutations confer increased cancer risk, for breast and other types, which is variable depending on the specific mutation. Of these, Large Genomic Rearrangements (LGRs) have been rarely ...reported; to date only eight LGRs have been published with just the Czech founder mutation, the deletion of exons 9 and 10, being molecularly characterized and studied extensively. The present study aimed to molecularly define and determine the contribution of two rare, apparently novel CHEK2 LGRs, among Greek breast cancer patients. These specifically involve a ~6 kb in-frame deletion of exons 2 & 3 that removes CHEK2's FHA domain and a ~7.5 kb in-frame deletion of exon 6, which removes an α-helix of CHEK2's kinase domain. The latter was identified in 5 out of 2355 (0.22%) patients tested, while haplotype analysis revealed a common disease-associated haplotype, suggesting a single common ancestor and a Greek founder. Although in-frame, this LGR is predicted to be damaging by a yeast-based functional assay and structure-function predictions. The present study highlights the existence of rare, population-specific, genomic events in a known breast cancer predisposing gene, which can explain a proportion of hereditary breast cancer. Identification of such mutation carriers is rather important since appropriate clinical actionability will be inferred.
Familial adenomatous polyposis, an autosomal dominant inherited disease caused by germline mutations within the APC gene, is characterized by early onset colorectal cancer as a consequence of the ...intrinsic phenotypic feature of multiple colorectal adenomatic polyps. The genetic investigation of Greek adenomatous polyposis families was performed in respects to APC and MUTYH germline mutations. Additionally, all available published mutations were considered in order to define the APC mutation spectrum in Greece.
A cohort of 25 unrelated adenomatous polyposis families of Greek origin has been selected. Genetic testing included direct sequencing of APC and MUTYH genes. APC gene was also checked for large genomic rearrangements by MLPA.
Analysis of the APC gene performed in a Greek cohort of twenty five FAP families revealed eighteen different germline mutations in twenty families (80%), four of which novel. Mutations were scattered between exon 3 and codon 1503 of exon 15, while no large genomic rearrangements were identified.
This concise report describes the spectrum of all APC mutations identified in Greek FAP families, including four novel mutations. It is concluded that the Greek population is characterized by genetic heterogeneity, low incidence of genomic rearrangements in APC gene and lack of founder mutation in FAP syndrome.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We report a case of a 58-year-old female with ovarian cancer. The patient presented with ascites, and the biopsies revealed a low-grade adenocarcinoma, either a serous papillary ovarian cancer with ...peritoneal implants or a primary peritoneal carcinoma. She received neoadjuvant chemotherapy and after 5 cycles achieved partial response, and then, she underwent a total hysterectomy/bilateral salpingo-oophorectomy. The patient underwent germline gene-panel testing for the detection of mutations in cancer predisposing genes. A truncating mutation in the Fanconi anemia complementation group M (FANCM) gene was detected in heterozygosity, namely, p.Arg658Ter (c.1972C>T, rs368728266). The patient’s family history is unremarkable, with no reported cases of breast or ovarian cancer, a fact that can be attributed to the significant lower penetrance of FANCM mutations.
The US government has proposed the development of scientific centers of excellence to solve global challenges. We propose such a center of excellence devoted to the genomic analysis of Mediterranean ...populations of all creeds. This genomic focus is rooted in the region's demographic history, builds on the area's rapidly developing expertise in human genetics, and will yield scientific discoveries of both local and global significance. The genome sequence data of Mediterranean populations will offer unique insights into human evolution and early human migration. The potent combination of highly consanguineous populations in the Mediterranean's southern and eastern rims and regional medical and scientific expertise could lead to the identification and characterization of many genes responsible for human disease. Such discoveries will enable genetic knowledge to be translated into medical knowledge that will benefit local populations and contribute substantially to the understanding of the genetic bases of human diseases worldwide.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Germline genetic variation has been suggested to influence the survival of breast cancer patients independently of tumor pathology. We have studied survival associations of genetic variants in two ...etiologically unique groups of breast cancer patients, the carriers of germline pathogenic variants in
or
genes. We found that rs57025206 was significantly associated with the overall survival, predicting higher mortality of
carrier patients with estrogen receptor-negative breast cancer, with a hazard ratio 4.37 (95% confidence interval 3.03-6.30,
= 3.1 × 10
). Multivariable analysis adjusted for tumor characteristics suggested that rs57025206 was an independent survival marker. In addition, our exploratory analyses suggest that the associations between genetic variants and breast cancer patient survival may depend on tumor biological subgroup and clinical patient characteristics.
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