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Stig E Bojesen,
Karen A Pooley,
Sharon E Johnatty,
Jonathan Beesley,
Kyriaki Michailidou,
Jonathan P Tyrer,
Stacey L Edwards,
Hilda A Pickett,
Howard C Shen,
Chanel E Smart, [......],
Simon A Gayther,
Paul D P Pharoah,
Roger R Reddel,
Ellen L Goode,
Mark H Greene,
Douglas F Easton,
Andrew Berchuck,
Antonis C Antoniou,
Georgia Chenevix-Trench,
Alison M Dunning
[show abstract]
[hide abstract]
ABSTRACT: TERT-locus SNPs and leukocyte telomere measures are reportedly associated with risks of multiple cancers. Using the Illumina custom genotyping array iCOGs, we analyzed ∼480 SNPs at the TERT locus in breast (n = 103,991), ovarian (n = 39,774) and BRCA1 mutation carrier (n = 11,705) cancer cases and controls. Leukocyte telomere measurements were also available for 53,724 participants. Most associations cluster into three independent peaks. The minor allele at the peak 1 SNP rs2736108 associates with longer telomeres (P = 5.8 × 10(-7)), lower risks for estrogen receptor (ER)-negative (P = 1.0 × 10(-8)) and BRCA1 mutation carrier (P = 1.1 × 10(-5)) breast cancers and altered promoter assay signal. The minor allele at the peak 2 SNP rs7705526 associates with longer telomeres (P = 2.3 × 10(-14)), higher risk of low-malignant-potential ovarian cancer (P = 1.3 × 10(-15)) and greater promoter activity. The minor alleles at the peak 3 SNPs rs10069690 and rs2242652 increase ER-negative (P = 1.2 × 10(-12)) and BRCA1 mutation carrier (P = 1.6 × 10(-14)) breast and invasive ovarian (P = 1.3 × 10(-11)) cancer risks but not via altered telomere length. The cancer risk alleles of rs2242652 and rs10069690, respectively, increase silencing and generate a truncated TERT splice variant.
Nature Genetics 03/2013; 45(4):371-384. · 35.53 Impact Factor
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Fergus J Couch,
Xianshu Wang,
Lesley McGuffog,
Andrew Lee,
Curtis Olswold,
Karoline B Kuchenbaecker,
Penny Soucy,
Zachary Fredericksen,
Daniel Barrowdale,
Joe Dennis, [......],
Chen Wang,
Steven Hart,
Kristen Stevens,
Jacques Simard,
Tomi Pastinen,
Vernon S Pankratz,
Kenneth Offit,
Douglas F Easton,
Georgia Chenevix-Trench,
Antonis C Antoniou
[show abstract]
[hide abstract]
ABSTRACT: BRCA1-associated breast and ovarian cancer risks can be modified by common genetic variants. To identify further cancer risk-modifying loci, we performed a multi-stage GWAS of 11,705 BRCA1 carriers (of whom 5,920 were diagnosed with breast and 1,839 were diagnosed with ovarian cancer), with a further replication in an additional sample of 2,646 BRCA1 carriers. We identified a novel breast cancer risk modifier locus at 1q32 for BRCA1 carriers (rs2290854, P = 2.7×10(-8), HR = 1.14, 95% CI: 1.09-1.20). In addition, we identified two novel ovarian cancer risk modifier loci: 17q21.31 (rs17631303, P = 1.4×10(-8), HR = 1.27, 95% CI: 1.17-1.38) and 4q32.3 (rs4691139, P = 3.4×10(-8), HR = 1.20, 95% CI: 1.17-1.38). The 4q32.3 locus was not associated with ovarian cancer risk in the general population or BRCA2 carriers, suggesting a BRCA1-specific association. The 17q21.31 locus was also associated with ovarian cancer risk in 8,211 BRCA2 carriers (P = 2×10(-4)). These loci may lead to an improved understanding of the etiology of breast and ovarian tumors in BRCA1 carriers. Based on the joint distribution of the known BRCA1 breast cancer risk-modifying loci, we estimated that the breast cancer lifetime risks for the 5% of BRCA1 carriers at lowest risk are 28%-50% compared to 81%-100% for the 5% at highest risk. Similarly, based on the known ovarian cancer risk-modifying loci, the 5% of BRCA1 carriers at lowest risk have an estimated lifetime risk of developing ovarian cancer of 28% or lower, whereas the 5% at highest risk will have a risk of 63% or higher. Such differences in risk may have important implications for risk prediction and clinical management for BRCA1 carriers.
PLoS Genetics 03/2013; 9(3):e1003212. · 8.69 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: Uncertainty exists about the origin of BRCA1 c.4035delA mutation which is prevalent in Baltic countries, with the highest frequency being in Lithuania (53% of all BRCA1 mutations), although formal founder mutation analysis by haplotype has not yet been undertaken. In this study we genotyped 78 unrelated BRCA1 c.4035delA mutation carriers families from Lithuania, Latvia, Poland and Russia. The results from the haplotype analyses were used to estimate the age of the mutation. Using maximum likelihood methods we estimated that the mutation arose approximately 1550 years (62 generations of 25 years) ago (ca. 5(th) century) somewhere in the present territory of Lithuania, in the area inhabited by ancient Baltic tribes at that time. Our results show that this mutation gradually entered the gene pool in the neighbouring countries.
European journal of medical genetics 12/2012; · 1.57 Impact Factor
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Kristen N Stevens,
Xianshu Wang,
Zachary Fredericksen,
Vernon S Pankratz,
Mark H Greene,
Irene L Andrulis,
Mads Thomassen,
Maria Caligo,
Katherine L Nathanson,
Anna Jakubowska, [......],
Jacques Simard,
Amanda B Spurdle,
Sue Healey,
Xiaoqing Chen,
Timothy R Rebbeck,
Douglas F Easton,
Georgia Chenevix-Trench,
Antonis C Antoniou,
Fergus J Couch,
Hans Ehrencrona
[show abstract]
[hide abstract]
ABSTRACT: Several common germline variants identified through genome-wide association studies of breast cancer risk in the general population have recently been shown to be associated with breast cancer risk for BRCA1 and/or BRCA2 mutation carriers. When combined, these variants can identify marked differences in the absolute risk of developing breast cancer for mutation carriers, suggesting that additional modifier loci may further enhance individual risk assessment for BRCA1 and BRCA2 mutation carriers. Recently, a common variant on 6p22 (rs9393597) was found to be associated with increased breast cancer risk for BRCA2 mutation carriers [hazard ratio (HR) = 1.55, 95 % confidence interval (CI) 1.25-1.92, p = 6.0 × 10(-5)]. This observation was based on data from GWAS studies in which, despite statistical correction for multiple comparisons, the possibility of false discovery remains a concern. Here, we report on an analysis of this variant in an additional 6,165 BRCA1 and 3,900 BRCA2 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). In this replication analysis, rs9393597 was not associated with breast cancer risk for BRCA2 mutation carriers (HR = 1.09, 95 % CI 0.96-1.24, p = 0.18). No association with ovarian cancer risk for BRCA1 or BRCA2 mutation carriers or with breast cancer risk for BRCA1 mutation carriers was observed. This follow-up study suggests that, contrary to our initial report, this variant is not associated with breast cancer risk among individuals with germline BRCA2 mutations.
Breast Cancer Research and Treatment 09/2012; 136(1):295-302. · 4.43 Impact Factor
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Penny Soucy,
Jonathan Beesley,
Xiaoqing Chen,
Lesley McGuffog,
Andrew Lee,
Daniel Barrowdale,
Sue Healey,
Niklas Loman,
Katja Harbst,
Annika Lindblom, [......],
Laura Papi,
Laura Ottini,
Paolo Radice,
Hilmi Ozcelik,
Gord Glendon,
Mads Thomassen,
Anne-Marie Gerdes,
Anne-Bine Skytte,
Georgia Chenevix-Trench,
Jacques Simard
[show abstract]
[hide abstract]
ABSTRACT: Several common alleles have been shown to be associated with breast and/or ovarian cancer risk for BRCA1 and BRCA2 mutation carriers. Recent genome-wide association studies of breast cancer have identified eight additional breast cancer susceptibility loci: rs1011970 (9p21, CDKN2A/B), rs10995190 (ZNF365), rs704010 (ZMIZ1), rs2380205 (10p15), rs614367 (11q13), rs1292011 (12q24), rs10771399 (12p11 near PTHLH) and rs865686 (9q31.2).
To evaluate whether these single nucleotide polymorphisms (SNPs) are associated with breast cancer risk for BRCA1 and BRCA2 carriers, we genotyped these SNPs in 12,599 BRCA1 and 7,132 BRCA2 mutation carriers and analysed the associations with breast cancer risk within a retrospective likelihood framework.
Only SNP rs10771399 near PTHLH was associated with breast cancer risk for BRCA1 mutation carriers (per-allele hazard ratio (HR) = 0.87, 95% CI: 0.81 to 0.94, P-trend = 3 × 10-4). The association was restricted to mutations proven or predicted to lead to absence of protein expression (HR = 0.82, 95% CI: 0.74 to 0.90, P-trend = 3.1 × 10-5, P-difference = 0.03). Four SNPs were associated with the risk of breast cancer for BRCA2 mutation carriers: rs10995190, P-trend = 0.015; rs1011970, P-trend = 0.048; rs865686, 2df-P = 0.007; rs1292011 2df-P = 0.03. rs10771399 (PTHLH) was predominantly associated with estrogen receptor (ER)-negative breast cancer for BRCA1 mutation carriers (HR = 0.81, 95% CI: 0.74 to 0.90, P-trend = 4 × 10-5) and there was marginal evidence of association with ER-negative breast cancer for BRCA2 mutation carriers (HR = 0.78, 95% CI: 0.62 to 1.00, P-trend = 0.049).
The present findings, in combination with previously identified modifiers of risk, will ultimately lead to more accurate risk prediction and an improved understanding of the disease etiology in BRCA1 and BRCA2 mutation carriers.
Breast cancer research: BCR 02/2012; 14(1):R33. · 5.24 Impact Factor
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Nasim Mavaddat,
Daniel Barrowdale,
Irene L Andrulis,
Susan M Domchek,
Diana Eccles,
Heli Nevanlinna,
Susan J Ramus,
Amanda Spurdle,
Mark Robson,
Mark Sherman, [......],
Kunle Odunsi,
Lara Sucheston,
Simon A Gayther,
Kate Nathanson,
Jenny Gross,
Christine Walsh,
Beth Karlan,
Georgia Chenevix-Trench,
Douglas F Easton,
Antonis C Antoniou
[show abstract]
[hide abstract]
ABSTRACT: Previously, small studies have found that BRCA1 and BRCA2 breast tumors differ in their pathology. Analysis of larger datasets of mutation carriers should allow further tumor characterization.
We used data from 4,325 BRCA1 and 2,568 BRCA2 mutation carriers to analyze the pathology of invasive breast, ovarian, and contralateral breast cancers.
There was strong evidence that the proportion of estrogen receptor (ER)-negative breast tumors decreased with age at diagnosis among BRCA1 (P-trend = 1.2 × 10(-5)), but increased with age at diagnosis among BRCA2, carriers (P-trend = 6.8 × 10(-6)). The proportion of triple-negative tumors decreased with age at diagnosis in BRCA1 carriers but increased with age at diagnosis of BRCA2 carriers. In both BRCA1 and BRCA2 carriers, ER-negative tumors were of higher histologic grade than ER-positive tumors (grade 3 vs. grade 1; P = 1.2 × 10(-13) for BRCA1 and P = 0.001 for BRCA2). ER and progesterone receptor (PR) expression were independently associated with mutation carrier status [ER-positive odds ratio (OR) for BRCA2 = 9.4, 95% CI: 7.0-12.6 and PR-positive OR = 1.7, 95% CI: 1.3-2.3, under joint analysis]. Lobular tumors were more likely to be BRCA2-related (OR for BRCA2 = 3.3, 95% CI: 2.4-4.4; P = 4.4 × 10(-14)), and medullary tumors BRCA1-related (OR for BRCA2 = 0.25, 95% CI: 0.18-0.35; P = 2.3 × 10(-15)). ER-status of the first breast cancer was predictive of ER-status of asynchronous contralateral breast cancer (P = 0.0004 for BRCA1; P = 0.002 for BRCA2). There were no significant differences in ovarian cancer morphology between BRCA1 and BRCA2 carriers (serous: 67%; mucinous: 1%; endometrioid: 12%; clear-cell: 2%). CONCLUSIONS/IMPACT: Pathologic characteristics of BRCA1 and BRCA2 tumors may be useful for improving risk-prediction algorithms and informing clinical strategies for screening and prophylaxis.
Cancer Epidemiology Biomarkers & Prevention 12/2011; 21(1):134-47. · 4.12 Impact Factor
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Christopher A Maxwell,
Javier Benítez,
Laia Gómez-Baldó,
Ana Osorio,
Núria Bonifaci,
Ricardo Fernández-Ramires,
Sylvain V Costes,
Elisabet Guinó,
Helen Chen,
Gareth J R Evans, [......],
Stephen B Gruber,
Conxi Lázaro,
Gabriel Capellá,
Lesley McGuffog,
Katherine L Nathanson,
Antonis C Antoniou,
Georgia Chenevix-Trench,
Markus C Fleisch,
Víctor Moreno,
Miguel Angel Pujana
[show abstract]
[hide abstract]
ABSTRACT: Differentiated mammary epithelium shows apicobasal polarity, and loss of tissue organization is an early hallmark of breast carcinogenesis. In BRCA1 mutation carriers, accumulation of stem and progenitor cells in normal breast tissue and increased risk of developing tumors of basal-like type suggest that BRCA1 regulates stem/progenitor cell proliferation and differentiation. However, the function of BRCA1 in this process and its link to carcinogenesis remain unknown. Here we depict a molecular mechanism involving BRCA1 and RHAMM that regulates apicobasal polarity and, when perturbed, may increase risk of breast cancer. Starting from complementary genetic analyses across families and populations, we identified common genetic variation at the low-penetrance susceptibility HMMR locus (encoding for RHAMM) that modifies breast cancer risk among BRCA1, but probably not BRCA2, mutation carriers: n = 7,584, weighted hazard ratio ((w)HR) = 1.09 (95% CI 1.02-1.16), p(trend) = 0.017; and n = 3,965, (w)HR = 1.04 (95% CI 0.94-1.16), p(trend) = 0.43; respectively. Subsequently, studies of MCF10A apicobasal polarization revealed a central role for BRCA1 and RHAMM, together with AURKA and TPX2, in essential reorganization of microtubules. Mechanistically, reorganization is facilitated by BRCA1 and impaired by AURKA, which is regulated by negative feedback involving RHAMM and TPX2. Taken together, our data provide fundamental insight into apicobasal polarization through BRCA1 function, which may explain the expanded cell subsets and characteristic tumor type accompanying BRCA1 mutation, while also linking this process to sporadic breast cancer through perturbation of HMMR/RHAMM.
PLoS Biology 11/2011; 9(11):e1001199. · 11.45 Impact Factor
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Antonis C Antoniou,
Jonathan Beesley,
Lesley McGuffog,
Olga M Sinilnikova,
Sue Healey,
Susan L Neuhausen,
Yuan Chun Ding,
Timothy R Rebbeck,
Jeffrey N Weitzel,
Henry T Lynch, [......],
Miguel de la Hoya,
Kristiina Aittomäki,
Heli Nevanlinna,
Jacques Simard,
Amanda B Spurdle,
Helene Holland,
Xiaoqing Chen,
Radka Platte,
Georgia Chenevix-Trench,
Douglas F Easton
[show abstract]
[hide abstract]
ABSTRACT: The known breast cancer susceptibility polymorphisms in FGFR2, TNRC9/TOX3, MAP3K1, LSP1, and 2q35 confer increased risks of breast cancer for BRCA1 or BRCA2 mutation carriers. We evaluated the associations of 3 additional single nucleotide polymorphisms (SNPs), rs4973768 in SLC4A7/NEK10, rs6504950 in STXBP4/COX11, and rs10941679 at 5p12, and reanalyzed the previous associations using additional carriers in a sample of 12,525 BRCA1 and 7,409 BRCA2 carriers. Additionally, we investigated potential interactions between SNPs and assessed the implications for risk prediction. The minor alleles of rs4973768 and rs10941679 were associated with increased breast cancer risk for BRCA2 carriers (per-allele HR = 1.10, 95% CI: 1.03-1.18, P = 0.006 and HR = 1.09, 95% CI: 1.01-1.19, P = 0.03, respectively). Neither SNP was associated with breast cancer risk for BRCA1 carriers, and rs6504950 was not associated with breast cancer for either BRCA1 or BRCA2 carriers. Of the 9 polymorphisms investigated, 7 were associated with breast cancer for BRCA2 carriers (FGFR2, TOX3, MAP3K1, LSP1, 2q35, SLC4A7, 5p12, P = 7 × 10(-11) - 0.03), but only TOX3 and 2q35 were associated with the risk for BRCA1 carriers (P = 0.0049, 0.03, respectively). All risk-associated polymorphisms appear to interact multiplicatively on breast cancer risk for mutation carriers. Based on the joint genotype distribution of the 7 risk-associated SNPs in BRCA2 mutation carriers, the 5% of BRCA2 carriers at highest risk (i.e., between 95th and 100th percentiles) were predicted to have a probability between 80% and 96% of developing breast cancer by age 80, compared with 42% to 50% for the 5% of carriers at lowest risk. Our findings indicated that these risk differences might be sufficient to influence the clinical management of mutation carriers.
Cancer Research 12/2010; 70(23):9742-54. · 7.86 Impact Factor
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Nancy Hamel,
Bing-Jian Feng,
Lenka Foretova,
Dominique Stoppa-Lyonnet,
Steven A Narod,
Evgeny Imyanitov,
Olga Sinilnikova, Laima Tihomirova,
Jan Lubinski,
Jacek Gronwald, [......],
Finn C Nielsen,
Mads Thomassen,
Drakoulis Yannoukakos,
Irene Konstantopoulou,
Vladimir Zajac,
Sona Ciernikova,
Fergus J Couch,
Celia M T Greenwood,
David E Goldgar,
William D Foulkes
[show abstract]
[hide abstract]
ABSTRACT: The BRCA1 mutation c.5266dupC was originally described as a founder mutation in the Ashkenazi Jewish (AJ) population. However, this mutation is also present at appreciable frequency in several European countries, which raises intriguing questions about the origins of the mutation. We genotyped 245 carrier families from 14 different population groups (Russian, Latvian, Ukrainian, Czech, Slovak, Polish, Danish, Dutch, French, German, Italian, Greek, Brazilian and AJ) for seven microsatellite markers and confirmed that all mutation carriers share a common haplotype from a single founder individual. Using a maximum likelihood method that allows for both recombination and mutational events of marker loci, we estimated that the mutation arose some 1800 years ago in either Scandinavia or what is now northern Russia and subsequently spread to the various populations we genotyped during the following centuries, including the AJ population. Age estimates and the molecular evolution profile of the most common linked haplotype in the carrier populations studied further suggest that c.5266dupC likely entered the AJ gene pool in Poland approximately 400–500 years ago. Our results illustrate that (1) BRCA1 c.5266dupC originated from a single common ancestor and was a common European mutation long before becoming an AJ founder mutation and (2) the mutation is likely present in many additional European countries where genetic screening of BRCA1 may not yet be common practice.Keywords: 5385insC; 5382insC; founder mutation; c.5266dupC; BRCA1; Europe
European Journal of HumanGenetics 11/2010; 19(3):300-306. · 4.40 Impact Factor
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Silvija Ozolina,
Olga Sinicka,
Eriks Jankevics,
Inna Inashkina,
Jan Lubinski,
Bohdan Gorski,
Jacek Gronwald,
Tatyana Nasedkina,
Olga Fedorova,
Ludmila Lyubchenko, Laima Tihomirova
[show abstract]
[hide abstract]
ABSTRACT: Uncertainty exists whether the 4154delA mutation of the BRCA1 gene detected in unrelated individuals from Latvia, Poland and Russia is a founder mutation with a common ancestral origin. To trace back this problem we analysed the mutation-associated haplotype of the BRCA1 intragenic SNPs as well as intragenic and nearby STR markers in mutation carriers from the aforementioned populations. The mutation-associated SNP alleles were found to be "T-A-A-A-A-G" for six intragenic SNPs of the BRCA1 gene (IVS8-58delT, 3232A/G, 3667A/G, IVS16-68A/G, IVS16-92A/G, IVS18+66G/A, respectively). The alleles 195, 154, 210 and 181 were found to be associated with the 4154delA mutation for STR markers D17S1325, D17S855, D17S1328 and D17S1320, correspondingly. Further analysis of markers in the 4154delA mutation carriers from all three populations allows us to assert that all analysed mutation carriers share a common ancestry.
Familial Cancer 01/2009; 8(1):1-4. · 1.30 Impact Factor
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Cancer Genetics and Cytogenetics 12/2007; 179(1):76-8. · 1.39 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: Germ-line mutations of the BRCA1 gene account for approximately half of the cases of hereditary breast/ovarian cancers. We have screened index patients from 15 breast cancer families and 8 sporadic breast cancer patients from Latvia for mutations in all coding exons of the BRCA1 gene, using combined Heteroduplex Analysis/SSCP followed by direct sequencing of the variants. BRCA1 germ-line mutations proved to be frequent in Latvian breast cancer patients, also in moderate-risk families and sporadic patients. Out of 23 cases a total of 8 patients (35%) exhibited three different mutations (5382insC, C61G, 4153delA). Interestingly, these three recurrent mutations accounted for all mutations in our sample set and no unique mutation was found. The 5382insC and C61G mutations accounted for 63% (5/8) and 25% (2/8) of all mutations, respectively. Allelotyping suggested a common founder in each recurrent mutation. Additional one-hundred hospital-based incident breast cancer patients were screened for the three mutations and 4 other 5382insC mutation carriers were identified (4%). Patients with C61G and 4153delA mutations were all Latvians, whilst the majority of 5382insC carriers (7/9=78%) were of Russian ethnicity, which is intriguing for the supposed Baltic origin of this mutation. Hum Mutat 14:92, 1999. © 1999 Wiley-Liss, Inc.
Human Mutation 06/1999; 14(1):92 - 92. · 5.69 Impact Factor
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Antonis C Antoniou,
Jonathan Beesley,
Lesley McGuffog,
Olga M Sinilnikova,
Sue Healey,
Susan L Neuhausen,
Yuan Chun Ding,
Timothy R Rebbeck,
Jeffrey N Weitzel,
Henry T Lynch, [......],
Heli Nevanlinna,
Jacques Simard,
Amanda B Spurdle,
Helene Holland,
Xiaoqing Chen,
Kconfab,
Radka Platte,
Georgia Chenevix-Trench,
Douglas F Easton,
CIMBA
[show abstract]
[hide abstract]
ABSTRACT: The known breast cancer susceptibility polymorphisms in FGFR2, TNRC9/TOX3, MAP3K1, LSP1, and 2q35 confer increased risks of breast cancer for BRCA1 or BRCA2 mutation carriers. We evaluated the associations of 3 additional single nucleotide polymorphisms (SNPs), rs4973768 in SLC4A7/NEK10, rs6504950 in STXBP4/COX11, and rs10941679 at 5p12, and reanalyzed the previous associations using additional carriers in a sample of 12,525 BRCA1 and 7,409 BRCA2 carriers. Additionally, we investigated potential interactions between SNPs and assessed the implications for risk prediction. The minor alleles of rs4973768 and rs10941679 were associated with increased breast cancer risk for BRCA2 carriers (per-allele HR = 1.10, 95% CI: 1.03-1.18, P = 0.006 and HR = 1.09, 95% CI: 1.01-1.19, P = 0.03, respectively). Neither SNP was associated with breast cancer risk for BRCA1 carriers, and rs6504950 was not associated with breast cancer for either BRCA1 or BRCA2 carriers. Of the 9 polymorphisms investigated, 7 were associated with breast cancer for BRCA2 carriers (FGFR2, TOX3, MAP3K1, LSP1, 2q35, SLC4A7, 5p12, P = 7 × 10(-11) - 0.03), but only TOX3 and 2q35 were associated with the risk for BRCA1 carriers (P = 0.0049, 0.03, respectively). All risk-associated polymorphisms appear to interact multiplicatively on breast cancer risk for mutation carriers. Based on the joint genotype distribution of the 7 risk-associated SNPs in BRCA2 mutation carriers, the 5% of BRCA2 carriers at highest risk (i.e., between 95th and 100th percentiles) were predicted to have a probability between 80% and 96% of developing breast cancer by age 80, compared with 42% to 50% for the 5% of carriers at lowest risk. Our findings indicated that these risk differences might be sufficient to influence the clinical management of mutation carriers.
70(23):9742-9754.
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Christopher A Maxwell,
Javier Benítez,
Laia Gómez-Baldó,
Ana Osorio,
Núria Bonifaci,
Ricardo Fernández-Ramires,
Sylvain V Costes,
Elisabet Guinó,
Helen Chen,
Gareth J R Evans, [......],
Stephen B Gruber,
Conxi Lázaro,
Gabriel Capellá,
Lesley McGuffog,
Katherine L Nathanson,
Antonis C Antoniou,
Georgia Chenevix-Trench,
Markus C Fleisch,
Víctor Moreno,
Miguel Angel Pujana
[show abstract]
[hide abstract]
ABSTRACT: Differentiated mammary epithelium shows apicobasal polarity, and loss of tissue organization is an early hallmark of breast carcinogenesis. In BRCA1 mutation carriers, accumulation of stem and progenitor cells in normal breast tissue and increased risk of developing tumors of basal-like type suggest that BRCA1 regulates stem/progenitor cell proliferation and differentiation. However, the function of BRCA1 in this process and its link to carcinogenesis remain unknown. Here we depict a molecular mechanism involving BRCA1 and RHAMM that regulates apicobasal polarity and, when perturbed, may increase risk of breast cancer. Starting from complementary genetic analyses across families and populations, we identified common genetic variation at the low-penetrance susceptibility HMMR locus (encoding for RHAMM) that modifies breast cancer risk among BRCA1, but probably not BRCA2, mutation carriers: n = 7,584, weighted hazard ratio ((w)HR) = 1.09 (95% CI 1.02-1.16), p(trend) = 0.017; and n = 3,965, (w)HR = 1.04 (95% CI 0.94-1.16), p(trend) = 0.43; respectively. Subsequently, studies of MCF10A apicobasal polarization revealed a central role for BRCA1 and RHAMM, together with AURKA and TPX2, in essential reorganization of microtubules. Mechanistically, reorganization is facilitated by BRCA1 and impaired by AURKA, which is regulated by negative feedback involving RHAMM and TPX2. Taken together, our data provide fundamental insight into apicobasal polarization through BRCA1 function, which may explain the expanded cell subsets and characteristic tumor type accompanying BRCA1 mutation, while also linking this process to sporadic breast cancer through perturbation of HMMR/RHAMM.
9(11):e1001199.
