OBJECTIVETo study BRCA1 gene expression in sporadic breast cancer in Han nationality and its relations to clinical pathological parameters.

METHODSImmunohistochemical method was used to detect the BRCA1 protein in paraffin embedded breast cancer tissue of 51 patients. The relationship between BRCA1 protein and clinical pathological features was analysed.

RESULTSBRCA1 protein was located in the nuclear of breast cancer cells. The rate of its down regulation of expression was 49.0% (25/51), which correlated reversely with c-erbB-2 protein, but did not correlate with histological grading, tumor size, lymph node involvement and patient age.

CONCLUSIONThe detection of BRCA1 protein expression may be a reflection of its gene alteration. So it may be a primary method for screening the susceptibility to breast cancer.

Adult ; Aged ; BRCA1 Protein ; analysis ; Breast Neoplasms ; genetics ; pathology ; Female ; Genes, BRCA1 ; Humans ; Immunohistochemistry ; Middle Aged

PURPOSE: Familial pancreatic cancer describes families with at least two first-degree relatives with pancreatic cancer that do not fulfil the criteria of other inherited tumor syndromes with increased risks of pancreatic cancer. Although much has been learned regarding the aggregation of pancreatic cancer in some families, the genetic basis for this familial aggregation is poorly understood. This study evaluated the prevalence of 10 Polish founder mutations in four genes among individuals from families with diagnosed familial pancreatic cancer syndrome and assessed their possible association with the familial pancreatic cancer (FPC) risk in Poland. MATERIALS AND METHODS: In this study, 400 FPC individuals and 4,000 control subjects were genotyped for founder mutations in BRCA1 (5382insC, 4153delA, C61G), CHEK2 (1100delC, IVS2+1G>A, del5395, I157T), NBS1 (657del5), and PALB2 (509_510delGA, 172_175delTTGT) genes. RESULTS: A statistically significant association was observed between the 172_175delTTGT mutation of the PALB2 gene and an increased risk of FPC syndrome (odds ratio [OR], 10.05; p=0.048). In addition, an increased risk of cancer was observed in the FPC family members with a BRCA1 mutation (OR, 6.72; p=0.006). Novel associations were found between the FPC family members with cancer and CHEK2 mutations (OR, 2.26; p=0.008) with a noticeable contribution of the missense variant, I157T of CHEK2 (OR, 2.17; p=0.026). CONCLUSION: The founder mutations in the genes, BRCA1, PALB2, and CHEK2, cause a small percentage of familial pancreatic cancer syndrome in the Polish population. Following confirmation in larger studies, these mutations can be added to the panel of genes to be tested in families with a diagnosis of FPC syndrome.
Diagnosis ; Genes, BRCA1 ; Humans ; Pancreatic Neoplasms* ; Poland ; Prevalence*

PURPOSE: Unclassified variants (UVs) of BRCA1 and BRCA2 genes are not defined as pathogenic for breast cancer, and their clinical significance currently remains undefined. Therefore, this study was conducted to identify potentially pathogenic UVs by comparing their prevalence between breast cancer patients and controls. MATERIALS AND METHODS: A total of 328 breast cancer patients underwent BRCA1/2 genetic screening at the National Cancer Center of Korea. Genetic variants of BRCA genes that were categorized as unclassified according to the Breast Cancer Information Core database were selected based on allelic frequency, after which candidate variants were genotyped in 421 healthy controls. We also examined family members of the study participants. Finally, the effects of amino acid substitutions on protein structure and function were predicted in silico. RESULTS: Genetic tests revealed 33 UVs in BRCA1 and 47 in BRCA2. Among 15 candidates genotyped in healthy controls, c.5339T>C in BRCA1 and c.6029T>G, c.7522G>A in BRCA2 were not detected. Moreover, the c.5339T>C variant in the BRCA1 gene was detected in four patients with a family history of breast cancer. This nonsynonymous variant (Leu1780Pro) in the BRCA1 C-terminal domain was predicted to have an effect on BRCA1 protein structure/function. CONCLUSION: This study showed that comparison of genotype frequency between cases and controls could help identify UVs of BRCA genes that are potentially pathogenic. Moreover, ourfindings suggest that c.5339T>C in BRCA1 might be a pathogenic variant for patients and their families.
Amino Acid Substitution ; BRCA1 Protein ; Breast Neoplasms* ; Breast* ; Computer Simulation ; Genes, BRCA1 ; Genes, BRCA2* ; Genetic Testing ; Genotype ; Humans ; Korea ; Prevalence

Breast Neoplasms ; genetics ; Disease Susceptibility ; Female ; Genes, BRCA1 ; Genes, BRCA2 ; Humans ; Mutation ; Ovarian Neoplasms ; genetics

Germline mutations in the BRCA1 and BRCA2 genes are strong genetic factors for predispositions to breast, ovarian, and other related cancers. This report describes a family with a history of breast and ovarian cancers that harbored a novel BRCA1 germline mutation. A single nucleotide deletion in intron 20, namely c.5332+4delA, was detected in a 43-year-old patient with breast cancer. This mutation led to the skipping of exon 20, which in turn resulted in the production of a truncated BRCA1 protein that was 1773 amino acids in length. The mother of the proband had died due to ovarian cancer and had harbored the same germline mutation. Ectopically expressed mutant BRCA1 protein interacted with the BARD1 protein, but showed a reduced transcriptional function, as demonstrated by the expression of cyclin B1. This novel germline mutation in the BRCA1 gene caused familial breast and ovarian cancers.
Adult ; Amino Acids ; BRCA1 Protein ; Breast Neoplasms* ; Breast* ; Cyclin B1 ; Exons* ; Genes, BRCA1 ; Genes, BRCA2 ; Germ-Line Mutation* ; Humans ; Introns ; Mothers ; Ovarian Neoplasms

No abstract available.
Genes, Tumor Suppressor ; BRCA2 Protein ; BRCA1 Protein ; Ovarian Neoplasms ; Breast Neoplasms

Most studies related to BRCA mutations have been performed in Western populations, and only a few small studies have been conducted in Korean populations. In 2007, the Korean Hereditary Breast Cancer (KOHBRA) Study was established to obtain evidence for the accurate risk assessment and management of hereditary breast and ovarian cancer (HBOC) in Korea. Between May 2007 and May 2010, the first phase of the KOHBRA Study was performed to estimate the prevalence of BRCA1/2 mutations among patients and their families at risk for HBOC. Between June 2010 and May 2013, the second phase of the KOHBRA Study was performed to identify the clinical characteristics and prognostic indicators of BRCA-related breast cancer and environmental and genetic modifiers of BRCA mutations and to develop a Korean BRCA risk calculator and nationwide genetic counseling network for HBOC. Herein, we review the results of the KOHBRA Study and describe the future perspectives of the study.
Breast ; Breast Neoplasms ; Genes, BRCA1 ; Genes, BRCA2 ; Genetic Counseling ; Humans ; Korea ; Neoplastic Syndromes, Hereditary ; Ovarian Neoplasms ; Prevalence ; Risk Assessment

Neurofibromatosis type 1 (NF1), which may occur as an autosom-al dominant disorder, is caused by the absence of neurofibromin protein due to somatic mutations in the NF1 gene, and it has been associated with an increased risk of breast cancer. Herein we describe a family with two women affected by both NF1 and early-onset breast cancer. We evaluated whether the concomitance of NF1 and early-onset breast cancer could be due to disease-causing mutations in both NF1 and BRCA1 gene in a Korean family with clinical features of both NF1 and hereditary breast cancer. Mutation analyses identified nonsense mutations in NF1 and BRCA1 genes. Our findings indicate that an awareness of the possible concomitance of NF1 and BRCA1 gene mutations is important for identifying the genetic origin of early-onset breast cancer in patients with NF1 to achieve early detection of cancers and decrease breast cancer-associated morbidity and mortality in these patients.
Breast ; Breast Neoplasms* ; Codon, Nonsense ; Female ; Genes, BRCA1 ; Genes, Neurofibromatosis 1 ; Germ-Line Mutation* ; Humans ; Mortality ; Neurofibromatosis 1* ; Neurofibromin 1

OBJECTIVE: BRCA mutational status is important in the management of ovarian cancer, but there is a lack of evidence supporting genetic testing in Asian populations. This study was performed to investigate the prevalence and prognostic outcomes of BRCA1/2 mutation and variant of unknown significance (VUS) in Korean patients diagnosed with epithelial ovarian cancer (EOC). METHODS: Among patients newly diagnosed with EOC between January 2007 and January 2017, those tested for germline BRCA1/2 mutation were studied, regardless of family history. Overall survival (OS) and progression-free survival (PFS) were compared between the patients with and without BRCA1/2 mutation and VUS. RESULTS: A total of 313 patients underwent BRCA testing: 88 patients had a BRCA1/2 mutation and 48 patients had a BRCA1/2 VUS (28.1% and 15.3%, respectively). There were no significant associations between BRCA1/2 mutation, BRCA1/2 wild-type, or BRCA1/2 VUS with age at diagnosis, histologic distribution, or residual disease status after primary cytoreductive surgery. BRCA1 mutation, including BRCA1 VUS, showed no difference in PFS or OS compared to BRCA1 wild-type. In contrast, BRCA2 mutation showed longer PFS than that of BRCA2 wild-type (P=0.04) or BRCA2 VUS (P=0.02). BRCA2 mutation, including BRCA2 VUS, did not show any difference in OS compared to BRCA2 wild-type. CONCLUSION: BRCA mutation and BRCA VUS had similar clinical characteristics and survival outcomes, except that BRCA2 mutation showed better PFS. The results of this study will help to understand the prognostic significance of BRCA mutation and VUS in Korean patients.
Asian Continental Ancestry Group ; Diagnosis ; Disease-Free Survival ; Genes, BRCA1 ; Genes, BRCA2 ; Genetic Testing ; Humans ; Korea ; Ovarian Neoplasms ; Prevalence

PURPOSE: To understand the involvement of BRCA1 gene in Korean breast and/or ovarian cancer families. MATERIALS AND METHODS: Germline mutations of BRCA1 gene were analyzed in 13 families which included 3 hereditary site-specific breast cancer families, 6 suspected breast cancer families, and 3 suspected breast-ovarian cancer family, and one Li-Fraumeni family by screening BRCA1 gene using single strand conformation polymorphism (SSCP) analysis on polymerase chain reaction (PCR) amplified genomic DNA and confirmed the results by sequencing. RESULTS: Including one family with previously reported nonsense mutation of BRCA1 gene, we detected two mutations in unrelated families. One newly identified mutation was frame shift mutation resulting from TG deletion in codon 1701, which results in a truncated BRCA1 protein, at codon 1714. CONCLUSION: The proportion of families who inherit the mutated BRCA1 gene seems to be small among Korean breast and/or ovarian cancer families.
BRCA1 Protein ; Breast Neoplasms ; Breast* ; Codon ; Codon, Nonsense ; DNA ; Frameshift Mutation ; Genes, BRCA1* ; Germ-Line Mutation* ; Humans ; Mass Screening ; Ovarian Neoplasms* ; Polymerase Chain Reaction