• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3353-3358
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• 2014

Breast cancer is the most common in women worldwide, with some 5-10% of all cases due to inherited mutations of BRCA1 and BRCA2 genes. Obesity, hormone therapy and use of alcohol are possible causes and over-expression of leptin in adipose tissue may also play a role. Normally surgery, radiation therapy and chemotherapy allow a good prognosis where screening measures are in place. New hope in treatment measures include adjuvant therapy, neoadjuvant therapy, and introduction of mono-clonal antibodies and enzyme inhibitors.

• Asian Pacific Journal of Cancer Prevention
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• 제16권17호
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• pp.7935-7941
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• 2015

The aim of this study was to implement massive parallel sequencing (MPS) technology in clinical genetics testing. We developed and tested an amplicon-based method for resequencing the BRCA1 and BRCA2 genes on an Illumina MiSeq to identify disease-causing mutations in patients with hereditary breast or ovarian cancer (HBOC). The coding regions of BRCA1 and BRCA2 were resequenced in 96 HBOC patient DNA samples obtained from different sample types: peripheral blood leukocytes, whole blood drops dried on paper, and buccal wash epithelia. A total of 16 random DNA samples were characterized using standard Sanger sequencing and applied to optimize the variant calling process and evaluate the accuracy of the MPS-method. The best bioinformatics workflow included the filtration of variants using GATK with the following cut-offs: variant frequency >14%, coverage ($>25{\times}$) and presence in both the forward and reverse reads. The MPS method had 100% sensitivity and 94.4% specificity. Similar accuracy levels were achieved for DNA obtained from the different sample types. The workflow presented herein requires low amounts of DNA samples (170 ng) and is cost-effective due to the elimination of DNA and PCR product normalization steps.

• Asian Pacific Journal of Cancer Prevention
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• 제16권6호
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• pp.2177-2185
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• 2015

Breast cancer is the most common malignancy in women around the world. About one in 12 women in the West develop breast cancer at some point in life. It is estimated that 5%-10% of all breast cancer cases in women are linked to hereditary susceptibility due to mutations in autosomal dominant genes. The two key players associated with high breast cancer risk are mutations in BRCA 1 and BRCA 2. Another highly important mutation can occur in TP53 resulting in a triple negative breast cancer. However, the great majority of breast cancer cases are not related to a mutated gene of high penetrance, but to genes of low penetrance such as CHEK2, CDH1, NBS1, RAD50, BRIP1 and PALB2, which are frequently mutated in the general population. In this review, we discuss the entire spectrum of mutations which are associated with breast cancer.

• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9607-9610
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• 2014

Breast cancer, a leading cause of death among women in most countries worldwide, is rapidly increasing in incidence in Vietnam. One of biomarkers is the disruption of the genetic material including epigenetic changes like DNA methylation. With the aim of finding hypermethylation at CpG islands of promoter of BRCA1 gene, belonged to the tumor suppressor gene family, as the biomarker for breast cancer in Vietnamese population, sensitive methyl specific PCR (MSP) was carried out on 115 samples including 95 breast cancer specimens and 20 normal breast tissues with other diseases which were obtained from Ho Chi Minh City Medical Hospital, Vietnam. The result indicated that the frequency of BRCA1 hypermethylation reached 82.1% in the cases (p<0.001). In addition, the DNA hypermethylation of this candidate gene increased the possibility to be breast cancer with high incidence via calculated odd ratios (p<0.05). In conclusion, hypermethylation of this candidate gene could be used as the promising biomarker application with Vietnamese breast cancer patients.

• Asian Pacific Journal of Cancer Prevention
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• 제16권9호
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• pp.4051-4055
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• 2015

The purpose of this study is to assess the effect of consanguinity on breast cancer incidence in Tunisia. We conducted a case-control study to evaluate the involvement of heterozygote and homozygote haplotypes of BRCA1 gene SNPs according to consanguinity among 40 cases of familial breast cancer, 46 cases with sporadic breast cancer and 34 healthy controls. We showed significant difference in consanguinity rate between breast cancer patients versus healthy controls P=0.001. Distribution of homozygous BRCA1 haplotypes among healthy women versus breast cancer patients was significantly different; p=0.02. Parental consanguinity seems to protect against breast cancer in the Tunisian population.

• Asian Pacific Journal of Cancer Prevention
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• 제17권4호
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• pp.1829-1832
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• 2016

Background: Breast cancer is the second most common malignancy among Nepalese women, accounting for 60% of the total cancer cases in females. Women diagnosed with germline mutations in BRCA1 like 185delAG, 1294del40 develop breast and/or ovarian cancer with a lifelong likelihood of up to 85% whereas presence of a mutation increases the risk for mutations to occur in other genes. The major objective of this study was to find the prevalence of these mutations in Nepalese cancer patients. Materials and Methods: This prospective study was carried out at two cancer hospitals in the Kathmandu valley over a period of 11 months. Irrespective of age group and stage of canceran appropriate amount of blood was withdrawn from 50 breast cancer patients and 20 controls. DNA was extracted manually and subjected to PCR using primers for 185delAG and 1294del40 mutations. PCR products were then digested with restriction enzyme (DdeII) followed by electrophoresis. Results: Prevalence of 185delAG in reference breast cancer patients was found to be 4/50 (8%) but no 1294del40 was apparent. Conclusions: Several mutations occurring in different exons of BRCA1 as well as mutations in other genes like BRCA2, for example, should also be taken in account.

• Journal of Genetic Medicine
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• 제8권2호
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• pp.105-112
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• 2011

목적: 유전성 유방암 가계에서 BRCA 유전자 돌연변이 결과 공유의 중요성은 가족검사를 통해 돌연변이 보인자를 확인하고 적극적인 암 발생 감시와 예방적 치료를 제공하는데 있다. 본 연구를 통하여 유전성 유방암 가계에서 돌연변이 사실에 대한 공유 정도, 등친 별 의사소통 차이와 이에 영향을 미치는 요인을 확인하고자 한다. 대상 및 방법: 한국인 유전성유방암 연구에 등록되어 BRCA1 또는 BRCA2 돌연변이가 확인된 발단자 106명을 대상으로 검사 후 유전상담, 유전성 유방암 지식도 평가, 돌연변이 사실에 대한 가족간의 의사소통 과정, 가족 검사 현황에 대해 설문조사를 시행하였다. 결과: 최종 응답자 106명 중 99명은 적어도 한 명 이상의 친족에게 자신의 유전자 검사결과를 알렸으며, 일등친 가족에게만 알린 경우는 68.7%, 일등친과 이등친 이상의 가족에게 돌연변이 사실을 알린 경우는 31.3%였다. 단변량 분석결과 일등친 가족에게만 검사결과를 알린 군이 이등친 또는 삼등친 가족에게 돌연변이 사실을 알린 군에 비해 기혼자의 비율이 더 높았으며, 검사 후 유전상담일로부터 설문조사 시점까지 기간이 유의하게 짧은 것으로 나타났다. 가족에게 돌연변이 사실을 알린 이유에 대해서는 가족들에게 BRCA 유전자 돌연변이 가능성과 유방암 발병위험성을 알리기 위함에 가장 큰 비중을 차지하였다. 결론: 유전성 유방암 가계에서 BRCA 돌연변이 사실에 대한 정보를 보다 많은 가족과 공유하기 위해서는 유전상담 시 환자 개개인의 가계 구조를 파악하여 차별화된 의사소통 방법을 제시해 주어야 할 것이다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권sup3호
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• pp.149-153
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• 2016

Breast cancer is the most common cancer in Iran. In the recent years an upward trend has been observed in the Iranian population. Early detection by molecular approaches may reduce breast cancer morbidity and mortality. We provided consultation to 3,782 women diagnosed with early onset breast cancer during the past 15 years (1999-2014). To establish a data set for BRCA gene alterations of the Iranian families at risk, two hundred and fifty four women who met our criteria were analyzed. A total number of 46 alterations including 18 variants with unknown clinical significance (39.1%), 18 missense mutations (39.1%), 7 Indels (15.2%) and 3 large rearrangement sequences (6%) were identified. Further scanning of affected families revealed that 49% of healthy relatives harbor identical causative mutations. This is the first report of comprehensive BRCA analysis in Iranian women with early onset breast cancer. Our findings provide valuable molecular data to support physicians as well as patients for the best decision making on disease management.

• Radiation Oncology Journal
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• 제33권2호
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• pp.149-154
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• 2015

Purpose: We performed exome sequencing in a breast cancer family without BRCA mutations. Materials and Methods: A family that three sisters have a history of breast cancer was selected for analysis. There were no family members with breast cancer in the previous generation. Genetic testing for BRCA mutation was negative, even by the multiplex ligation-dependent probe amplification method. Two sisters with breast cancer were selected as affected members, while the mother of the sisters was a non-affected member. Whole exome sequencing was performed on the HiSeq 2000 platform with paired-end reads of 101 bp in the three members. Results: We identified 19,436, 19,468, and 19,345 single-nucleotide polymorphisms (SNPs) in the coding regions. Among them, 8,759, 8,789, and 8,772 were non-synonymous SNPs, respectively. After filtering out 12,843 synonymous variations and 12,105 known variations with indels found in the dbSNP135 or 1000 Genomes Project database, we selected 73 variations in the samples from the affected sisters that did not occur in the sample from the unaffected mother. Using the Sorting Intolerant From Tolerant (SIFT), PolyPhen-2, and MutationTaster algorithms to predict amino acid substitutions, the XCR1, DLL1, TH, ACCS, SPPL3, CCNF, and SRL genes were risky among all three algorithms, while definite candidate genes could not be conclusively determined. Conclusion: Using exome sequencing, we found 7 variants for a breast cancer family without BRCA mutations. Genetic evidence of disease association should be confirmed by future studies.

• Journal of Genetic Medicine
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• 제7권1호
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• pp.67-77
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• 2010

목 적: 본 연구는 한국인 BRCA 유전자 돌연변이 가계구성원들을 대상으로 암진단 및 돌연변이 보유 여부가 심리 상태와 삶의 질에 미치는 영향을 알아보기 위해 시행되었다. 대상 및 방법: BRCA 유전자 돌연변이를 가진 13가계에서 암에 이환된 보인자 17명, 이환되지 않은 보인자 16명, 건강한 비보인자 13명이 본 연구의 분석에 포함되었다. 이 세 군을 대상으로 우울, 불안, 낙관, 유전성 유방암관련 지식수준과 삶의 질을 설문을 통하여 평가하였다. 결 과: 설문시기는 유전자 검사 후 평균 21개월(6-35)로 세 군 간의 차이는 없었다(P=0.254). 세 군 간의 우울, 낙관, 육체적 삶의 질은 유사했다. 불안은 세 군 모두에서 일반인 보다 상승되어 있었다. 이환된 보인자의 정신적 삶의 질은 암에 이환된 보인자가 다른 두 군에 비해 유의하게 낮았다(P=0.009, P=0.017). 다변량 분석 결과 정신적 삶의 질에 영향을 미친 인자는 암이환여부(P=0.043)와 직업유무(P=0.008) 였다. 결 론: 같은 돌연변이 가계 내에서 돌연변이 유무는 우울, 불안, 낙관에서 심리적반작용을 일으키지 않았으나, 돌연변이 가계 구성원의 불안 수준은 돌연변이 유무에 관계 없이 높았다. 본 연구는 소규모 표본을 대상으로 한 단면적 연구이나, BRCA 유전자 검사에 수반될 수 있는 심리적 스트레스 및 그에 대한 대처법을 수립하는 데 기초연구로 의의를 가진다.