乳腺癌BRCA1基因突变及其蛋白表达研究

目的：探讨散发性乳腺癌的BRCA1基因突变及其蛋白表达与临床病理因素的关系。方法：收集乳腺癌患者外周血102份、新鲜肿瘤组织30份，分别采用PCR-SSCP、DHPLC和基因测序对BRCA1基因第2、8-1、8-2和20外显子进行突变检测；对104例肿瘤组织切片进行免疫组化染色标记BRCA1蛋白表达，分析免疫组化结果与临床资料的关系。结果：分别在外显子8-1和8-2的28821和28978位点上发现3例碱基缺失和置换现象。BRCA1蛋白在乳腺癌组织中表达下降，且与患者生存状态有关。结论：在中国散发性乳腺癌患者中BRCA1基因外显子2、8和20的突变率较低(2．3％)，可以认为在普通中国人群中乳腺癌的发生与该部分碱基序列突变的关系不大，但BRCA1蛋白低表达乳腺癌患者复发的危险性增大。     

38例散发乳腺癌患者BRCA1基因突变检测

目的：分析３８例散发乳腺癌患者ＢＲＣＡ１基因突变情况及突变位置。方法：应用ＰＣＲ－ＳＳＣＰ（Ｓｉｎｇｌｅ－ｓｔｒａｎｄｅｄ ｃｏｎｆｏｒｍａｔｉｏｎａｌ ｐｏｌｙｍｏｒｐｈｉｓｍ,ＳＳＣＰ）和直接测序方法。结果：４／３８例患者ＢＲＣＡ１基因有突变,突变例数占总例和的１０．５％,其中３例突变位置在内含子的拼接区,一例突变位置在１１号外显子上。结论：筛查ＢＲＣＡ１基因突变对于乳腺癌患病风险评估,发病检     

中国乳腺癌家族BRCA1突变分析

为了探讨中国乳腺癌家族中BRCAl基因突变情况,我们收集了15个乳腺癌家系,共41个对象,其中23例为乳腺癌患者,采用聚合酶链反应-单链构像多态性分析(PCR-SSCP)、直接DNA测序法对BRCA1编码基因进行了全序列分析。结果发现在15个家系中有4例(3种)基因突变,突变比例为26.7％(4/15)。其中一例2228insC为插入突变,致编码子711处蛋白截短;另3例(2种)突变为1884A→T和3232 A→G,分别引起单个氨基酸改变。我们认为BRCA1为家族性乳腺癌的遗传基因;在BRCA1以外还存在其他的乳腺癌易感基因。     

186例乳腺癌患者BRCA1基因突变检测

目的 分析186例散发乳腺癌患者肿瘤易感基因BRCA1（breast and orarian cancer susceptibility gene,BRCA1)突变情况及突变位置。方法 应用PCR－SSCP（single-stranded canformational polymorphs,SSCP)和直接测序方法定位,检测乳腺癌部分患者部分BRCA1基因外显子和内含子与外显子之间接拼区突变及突变位置。结果 186例患者中,有13例发生BRCA1基因突变,突变例数占总例数的7．0％,其中8例突变位置在内含子与外显子的拼接区,5例突变位置在外显子上。结论 筛查BRCA1基因突变对于乳腺癌患病风险评估、发病检测、早期诊断及基因治疗具有重要的临床意义。     

华东地区乳腺癌散发病例BRCA1、BRCA2基因突变

目的：探讨华东地区乳腺癌散发病例BRCA1及BRCA2基因突变情况。方法：应用PCR-SSCP-Sequencing方法,对复旦大学附属肿瘤医院79例随机乳腺癌患者的癌组织及癌旁正常乳腺组织的标本进行BRCA1和BRCA2部分基因的突变检测,共6个外显子（BRCA1中的第2、11、22外显子,BRCA2中的第9,14,22外显子）23对引物。结果：发现在BRCA1和cDNA 2430碱基处存在一个T→C的单个碱基的变化,应用RFLP方法在人群中证实为一单核苷酸多态。此SNP的分布在病例及对照中等位基因频率存在差异,但并未达到显著性水平。结论：提示华东地区人群的乳腺癌群体中的BRCA1及BRCA2的突变十分罕见。     

BRCA1、BRCA2基因突变与乳腺癌风险预测及治疗

BRCA1/2基因突变与肿瘤的发生关系密切,其机制主要为BRCA1/2蛋白在细胞分裂过程中对染色体结构和基因序列的完整性起到监护作用,从而预防肿瘤的发生。但BRCA1/2基因突变在乳腺癌中的作用机制始终存在争议。探讨BRCA1/2基因的结构与功能、常见突变类型和位点及它们在乳腺癌临床风险预测中的作用,可为临床靶向治疗提供指导。     

38例散发乳腺癌患者BRCA1基因突变检测

肿瘤易感基因BRCA1(breast and ovarian canoer suscepti-bility gene,BRCA1)与乳腺癌,卵巢癌发生有密切联系,它的失活可导致细胞的恶性转化和肿瘤的发生.BRCA1基因突变者患癌的风险远高于普通群体,对于有家族史的高危人群中筛查BRCA1基因,对于乳腺癌卵巢癌患者风险评估,发病检测,早期诊断及今后的基因治疗等都有很重要的临床意义.     

乳腺癌BRCA1基因突变及其蛋白表达研究

目的 :探讨散发性乳腺癌的BRCA1基因突变及其蛋白表达与临床病理因素的关系。方法 :收集乳腺癌患者外周血 10 2份、新鲜肿瘤组织 30份 ,分别采用PCR SSCP、DHPLC和基因测序对BRCA1基因第 2、8- 1、8- 2和 2 0外显子进行突变检测 ;对 10 4例肿瘤组织切片进行免疫组化染色标记BRCA1蛋白表达 ,分析免疫组化结果与临床资料的关系。结果 :分别在外显子 8- 1和 8- 2的 2 882 1和 2 8978位点上发现 3例碱基缺失和置换现象。BRCA1蛋白在乳腺癌组织中表达下降 ,且与患者生存状态有关。结论 :在中国散发性乳腺癌患者中BRCA1基因外显子 2、8和 2 0的突变率较低 (2 3% ) ,可以认为在普通中国人群中乳腺癌的发生与该部分碱基序列突变的关系不大 ,但BRCA1蛋白低表达乳腺癌患者复发的危险性增大     

中国家族性和早发性乳腺癌BRCA1基因突变的研究

目的　研究中国家族性和早发性乳腺癌患者的BRCA1基因突变情况。方法　选取 4 1例家族性和早发性乳腺癌患者的外周血单个核细胞DNA ,应用PCR SSCP和DNA序列测定方法 ,对BRCA1基因全序列进行突变检测和分析。结果　 4 1例乳腺癌患者中 ,3例发生BRCA1疾病相关性突变 ,其中年龄 <35岁的患者 2例 ,具有乳腺癌家族史的患者 1例。结论　中国早发性乳腺癌患者的BRCA1突变发生率与西方国家相近 ,而家族性乳腺癌患者的突变发生率明显低于西方国家。     

散发性乳腺癌患者BRCA1基因突变分析

目的：探讨BRCA1基因突变在散发性乳腺癌发生和发展中的作用及在乳腺癌临床诊断和治疗中的应用前景。方法：应用PCR-SSCP和直接测序法检测30例散发性乳腺癌和15例正常乳腺组织中RRCA1基因外显子2、11和20的突变情况。结果：15例正常乳腺组织在3个外显子上郜未显示电泳异常．30例乳腺癌中有6例在外显子2上显示电泳条带异常．其中4例经测序证实有突变，1例在外显子2上，3例在内含子拼接区。BRCA1基因突变率在初诊年龄、临床分期和肿瘤体积上差异无统计学意义．但与肿瘤转移密切相关。结论：BRCA1基因突变与散发性乳腺癌的发生和发展密切相关，该基因突变筛查可作为一种预后指标。     

Identification of Mutation in Exon11 of BRCA1 Gene in Bangladeshi Patients with Breast Cancer

Background: Worldwide, breast cancer is the leading cause of cancer death in female, in Bangladesh breast cancer is the second leading cancer in both sexes, and in women it occupied the top position. Highly penetrant mutations in BRCA1 gene constitute high risk of breast cancer. The spectrum of BRCA1 gene mutations varies in different population. The objective of this study was to identify mutation in exon11 of BRCA1 gene in Bangladeshi breast cancer patients. Methods: Genomic DNA was extracted from the histopathologically diagnosed formalin fixed paraffin embedded (FFPE) breast cancer tissues of 65 adult female patients. Two regions of exon11 of the BRCA1 gene were amplified and the amplicons were sequenced using Sanger sequencing. The sequenced nucleotides were analyzed and blast using NCBI nucleoblast. Selected demographic, reproductive and medical histories were collected and analyzed using SPSS version 20. Results: The mean age of the patients was 46 years and the mean age at diagnosis was 44.64 years. The patients were married and had 2.65 ± 1.22 children except one was nulliparous, the mean age of menarche was 12.67 years. All patients had children, breastfed the babies for an average 1.5 years. Only 13.6% of the patients had hypertension and the rest had no comorbidity. The family history for cancer (breast and other cancer) was negative. Three novel mutations were found in a patient. Two among the three mutant sequences had effect on amino acid coding (DNA sequence change g.852G>C and g.709G>A and amino acid changes p.Gln284His and p.Glu237Lys respectively).  Conclusion: We found three novel mutations in Bangladeshi breast cancer patients. This finding indicates the necessity to study the mutation profile of whole BRCA1 gene in our population for cancer risk prediction.     

50例乳腺癌患者BBCA1基因exon11突变研究

[目的]检测50例乳腺癌患者BRCA1基因exon11突变情况及突变位置,探讨BRCA1突变与乳腺癌的关系。[方法]采取50例乳腺癌全血标本为实验组,28例非癌乳腺全血标本为对照组。应用PCR和DNA直接测序法检测所有标本BRCA1基因exon11的突变情况。[结果]28例非癌乳腺组织BRCA1基因exon11未检出突变,50例乳腺癌中有6例发生基因突变。占总例数的12．0％。6例中2例发生多个位点突变,19号标本5个突变位点：2685T→C,2201C→T。2731C→T,3232A→G,3667A→G;30号标本2个突变位点：2685T→C;204T→A。8个位点为错义突变：2532T→C,2685T→C2例,2731C→T,3232A→G,3667A→G2例,2041T→A。3个位点为同义突变：2630T→G2例,2201C→T。发现两个新位点2201位和2731位。[结论]BRCA1基因exon11突变与乳腺癌的发生关系密切,对其进行检测可能对乳腺癌的患病风险评估及早期诊断具有重要意义。     

Nonsense Mutation at Codon 63 of the BRCA1 Gene in Japanese Breast Cancer Patients

The involvement of abnormalities of the BRCA1 gene in breast cancers in Japanese patients without any family history of this cancer was investigated by polymerase chain reaction-based single-strand conformation polymorphism analysis of the DNA sequences corresponding to the zinc finger domain (exons 2, 3 and 5) and the binding domain with Rad51 (exon 11) of the BRCA1 protein. An identical nonsense mutation at codon 63 (TTA to TAA) was found in 2 of 56 (3.5%) breast cancers from independent patients. The nucleotide change was also detected in the DNAs from non-cancerous tissues of both patients and therefore was a germline mutation. One of the patients was a member of a pedigree involving 3 ovarian cancer and 1 gastric cancer patients, while the other patient had no family history of malignancy. The same germline mutation at codon 63 was reported in four other independent Japanese pedigrees with frequent breast cancer, but not in such families in other countries. These observations suggest that the mutation commonly originated from a single Japanese ancestor. No other mutation of the BRCA1 gene was observed in the samples analyzed in this study. A low incidence of germline mutation and the absence of somatic mutation suggest that the aberration of the BRCA1 gene is involved only in a subset of Japanese breast cancers.     

231例乳腺癌患者乳腺癌易感基因 BRCA1 的突变检测及分析

目的：研究中国妇女BRCA1基因突变与遗传性、家族性和早发性乳腺癌的关系。方法：选取231例乳腺癌患者石蜡标本,显微切割提取癌组织,酚抽提法提取DNA,紫外分光光度仪测定DNA纯度及含量,PCR扩增exon2、exon11和exon20片段直接测序,与基因库序列比对分析其突变情况。结果：231例乳腺癌中发现突变33例,突变率为14．28％,统计分析发现,≤35岁年龄组与36－45岁组比较,P值为0．724,无统计学差异。46－55岁年龄组与＞55岁组比较,P 值为0．868,亦无统计学差异。将上述两组合并后统计发现,≤45岁年龄组患者突变率高于＞45岁组患者,P值为0．002,有显著统计学差异。结论：BRCA1突变与乳腺癌尤其是早发性乳腺癌密切相关。     

Dicer1基因单核苷酸多态性与浙江地区BRCA1/BRCA2阴性家族性乳腺癌的相关性研究

[目的]研究Dicer1基因单核苷酸多态性与浙江地区BRCA1/BRCA2阴性家族性乳腺癌易感性的相关性.[方法]选择3个单核苷酸多态性位点(rs74899136、rs2297730和rs147668333),采用PCR测序方法对65例BRCA1/BRCA2阴性家族性乳腺癌患者和100名健康女性进行分析,x2检验比较两组在等位基因和基因型分布频率上的差异,非条件Logistic回归评价多态性位点与乳腺癌易感性的相关性.[结果]rs2297730的G等位基因和A/G基因型在乳腺癌病例组中的分布频率显著高于对照组(OR=1.873,95％CI:1.174～2.988,P=0.008;OR=3.133,95％CI:1.562～6.287,P=0.004).另外2个多态性位点等位基因和基因型分布频率在两组间无显著差异(P＞0.05).rs2297730在共显性、显性、超显性以及加性遗传模式下与乳腺癌相关(P＜0.05),最佳遗传模式为显性.[结论] Dicer1基因rs2297730与浙江地区BRCA 1/BRCA2阴性家族性乳腺癌易感性相关.     

Premature Menopause in Patients with BRCA1 Gene Mutation

This study was undertaken with regard to the gonadotropin theory of ovarian cancer advocated in the literature and was designed to disclose specific features of ovarian morphology in carriers of the BRCA1 gene mutation. We enrolled 171 patients and divided them into two groups: A (n=90)—operated for breast cancer (30 patients with and 60 without the BRCA1 mutation); B (n=81)—with the BRCA1 mutation qualified for preventive adnexectomy. According to the authors’ classification described herein, some patients without the BRCA1 mutation retained “signs of estrogenization” in menopausal ovaries, revealing the role of estrogens as a factor promoting mammary carcinogenesis in these patients. A tendency to premature menopause was observed in BRCA1 mutation carriers of groups A and B as evidenced by the final menorrhea appearing at a younger age and almost total absence of “signs of estrogenization” in menopausal ovaries. It is concluded from these findings that earlier menopause in carriers of the BRCA1 mutation is associated with hypergonadotropic activity and may predispose to ovarian cancer at younger age.     

Haplotype Analysis of BRCA1 Gene D17S855 and D17S1322 Markers in Iranian Familial Breast Cancer Patients

Background: Breast cancer molecular analysis by linkage analysis has the advantage of facilitating early diagnosis in asymptomatic genetic carriers, with a view to the preventive followup of these subjects and genetic counseling. The aim of this study was to evaluate BRCA1 gene D17S855 and D17S1322 markers in breast cancer patients. Materials and Methods: A series of 85 BC patients and 85 unrelated healthy women were recruited for haplotype analysis performed using two short tandem repeat markers located within the BRCA1 gene locus. Each marker was amplified with PCR genomic DNA from each individual and fluorescently endlabeled primers. Results: Both D17S855 and D17S1322 markers included 12 kinds of alleles. Results indicate that most of the BC patients shared two common 121150 (11.2%, RR1.56 and p0.02) and 121146 (5.6%, RR1.9 and p0.02) haplotypes. Conclusions: Our results should be helpful to understand the haplotype phase in the BRCA1 gene and establish a genetic screening strategy in the Iranian population.     

Platinum Sensitivity in a BRCA1 Mutation Carrier with Advanced Breast Cancer

Although BRCA1-associated breast carcinomas are frequently detected in nodal-negative stage, they typically present with an aggressive histopathological phenotype that is reflected by a poor prognosis and an increased risk for distant metastatic spread. Recent in vitro data suggest a high sensitivity of BRCA1-associated carcinomas to platinum-based chemotherapy and a lower sensitivity to anthracyclines and taxanes. This is explained by the key role of BRCA1 in DNA double-strand repair via homologous recombination, thereby leading to a higher sensitivity to DNA intercalating agents, such as platinum. Here we present the case of a woman suffering from BRCA1-associated metastatic breast carcinoma that was resistant to docetaxel, but responded strongly to cisplatin-containing chemotherapy. This supports the rationale of ongoing clinical studies.