Publications by authors named "Pascaline Berthet"

63 Publications

Classification of 101 BRCA1 and BRCA2 variants of uncertain significance by cosegregation study: A powerful approach.

Am J Hum Genet 2021 Oct 30;108(10):1907-1923. Epub 2021 Sep 30.

Service de Génétique, Hôpital Européen Georges Pompidou, Paris 75015, France.

Up to 80% of BRCA1 and BRCA2 genetic variants remain of uncertain clinical significance (VUSs). Only variants classified as pathogenic or likely pathogenic can guide breast and ovarian cancer prevention measures and treatment by PARP inhibitors. We report the first results of the ongoing French national COVAR (cosegregation variant) study, the aim of which is to classify BRCA1/2 VUSs. The classification method was a multifactorial model combining different associations between VUSs and cancer, including cosegregation data. At this time, among the 653 variants selected, 101 (15%) distinct variants shared by 1,624 families were classified as pathogenic/likely pathogenic or benign/likely benign by the COVAR study. Sixty-six of the 101 (65%) variants classified by COVAR would have remained VUSs without cosegregation data. Of note, among the 34 variants classified as pathogenic by COVAR, 16 remained VUSs or likely pathogenic when following the ACMG/AMP variant classification guidelines. Although the initiation and organization of cosegregation analyses require a considerable effort, the growing number of available genetic tests results in an increasing number of families sharing a particular variant, and thereby increases the power of such analyses. Here we demonstrate that variant cosegregation analyses are a powerful tool for the classification of variants in the BRCA1/2 breast-ovarian cancer predisposition genes.
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http://dx.doi.org/10.1016/j.ajhg.2021.09.003DOI Listing
October 2021

Diagnostic chest X-rays and breast cancer risk among women with a hereditary predisposition to breast cancer unexplained by a BRCA1 or BRCA2 mutation.

Breast Cancer Res 2021 08 3;23(1):79. Epub 2021 Aug 3.

Institut Claudius Regaud - IUCT-Oncopole, Service d'Oncologie Médicale, Toulouse, France.

Background: Diagnostic ionizing radiation is a risk factor for breast cancer (BC). BC risk increases with increased dose to the chest and decreases with increased age at exposure, with possible effect modification related to familial or genetic predisposition. While chest X-rays increase the BC risk of BRCA1/2 mutation carriers compared to non-carriers, little is known for women with a hereditary predisposition to BC but who tested negative for a BRCA1 or BRCA2 (BRCA1/2) mutation.

Methods: We evaluated the effect of chest X-rays from diagnostic medical procedures in a dataset composed of 1552 BC cases identified through French family cancer clinics and 1363 unrelated controls. Participants reported their history of X-ray exposures in a detailed questionnaire and were tested for 113 DNA repair genes. Logistic regression and multinomial logistic regression models were used to assess the association with BC.

Results: Chest X-ray exposure doubled BC risk. A 3% increased BC risk per additional exposure was observed. Being 20 years old or younger at first exposure or being exposed before first full-term pregnancy did not seem to modify this risk. Birth after 1960 or carrying a rare likely deleterious coding variant in a DNA repair gene other than BRCA1/2 modified the effect of chest X-ray exposure.

Conclusion: Ever/never chest X-ray exposure increases BC risk 2-fold regardless of age at first exposure and, by up to 5-fold when carrying 3 or more rare variants in a DNA repair gene. Further studies are needed to evaluate other DNA repair genes or variants to identify those which could modify radiation sensitivity. Identification of subpopulations that are more or less susceptible to ionizing radiation is important and potentially clinically relevant.
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http://dx.doi.org/10.1186/s13058-021-01456-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8336294PMC
August 2021

Breast and Prostate Cancer Risks for Male BRCA1 and BRCA2 Pathogenic Variant Carriers Using Polygenic Risk Scores.

J Natl Cancer Inst 2021 Jul 28. Epub 2021 Jul 28.

Department of Molecular Medicine, University La Sapienza, Rome, Italy.

Background: Recent population-based female breast cancer and prostate cancer polygenic risk scores (PRS) have been developed. We assessed the associations of these PRS with breast and prostate cancer risks for male BRCA1 and BRCA2 pathogenic variant carriers.

Methods: 483 BRCA1 and 1,318 BRCA2 European ancestry male carriers were available from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). A 147-single nucleotide polymorphism (SNP) prostate cancer PRS (PRSPC) and a 313-SNP breast cancer PRS were evaluated. There were three versions of the breast cancer PRS, optimized to predict overall (PRSBC), estrogen-receptor (ER) negative (PRSER-) or ER-positive (PRSER+) breast cancer risk.

Results: PRSER+ yielded the strongest association with breast cancer risk. The odds ratios (ORs) per PRSER+ standard deviation estimates were 1.40 (95% confidence interval [CI] =1.07-1.83) for BRCA1 and 1.33 (95% CI = 1.16-1.52) for BRCA2 carriers. PRSPC was associated with prostate cancer risk for both BRCA1 (OR = 1.73, 95% CI = 1.28-2.33) and BRCA2 (OR = 1.60, 95% CI = 1.34-1.91) carriers. The estimated breast cancer ORs were larger after adjusting for female relative breast cancer family history. By age 85 years, for BRCA2 carriers, the breast cancer risk varied from 7.7% to 18.4% and prostate cancer risk from 34.1% to 87.6% between the 5th and 95th percentiles of the PRS distributions.

Conclusions: Population-based prostate and female breast cancer PRS are associated with a wide range of absolute breast and prostate cancer risks for male BRCA1 and BRCA2 carriers. These findings warrant further investigation aimed at providing personalized cancer risks for male carriers and to inform clinical management.
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http://dx.doi.org/10.1093/jnci/djab147DOI Listing
July 2021

Gene- and pathway-level analyses of iCOGS variants highlight novel signaling pathways underlying familial breast cancer susceptibility.

Int J Cancer 2021 04 9;148(8):1895-1909. Epub 2021 Jan 9.

Département d'Anticipation et de Suivi des Cancers, Oncogénétique Clinique, Institut Paoli-Calmettes, Marseille, France.

Single-nucleotide polymorphisms (SNPs) in over 180 loci have been associated with breast cancer (BC) through genome-wide association studies involving mostly unselected population-based case-control series. Some of them modify BC risk of women carrying a BRCA1 or BRCA2 (BRCA1/2) mutation and may also explain BC risk variability in BC-prone families with no BRCA1/2 mutation. Here, we assessed the contribution of SNPs of the iCOGS array in GENESIS consisting of BC cases with no BRCA1/2 mutation and a sister with BC, and population controls. Genotyping data were available for 1281 index cases, 731 sisters with BC, 457 unaffected sisters and 1272 controls. In addition to the standard SNP-level analysis using index cases and controls, we performed pedigree-based association tests to capture transmission information in the sibships. We also performed gene- and pathway-level analyses to maximize the power to detect associations with lower-frequency SNPs or those with modest effect sizes. While SNP-level analyses identified 18 loci, gene-level analyses identified 112 genes. Furthermore, 31 Kyoto Encyclopedia of Genes and Genomes and 7 Atlas of Cancer Signaling Network pathways were highlighted (false discovery rate of 5%). Using results from the "index case-control" analysis, we built pathway-derived polygenic risk scores (PRS) and assessed their performance in the population-based CECILE study and in a data set composed of GENESIS-affected sisters and CECILE controls. Although these PRS had poor predictive value in the general population, they performed better than a PRS built using our SNP-level findings, and we found that the joint effect of family history and PRS needs to be considered in risk prediction models.
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http://dx.doi.org/10.1002/ijc.33457DOI Listing
April 2021

National recommendations of the French Genetics and Cancer Group - Unicancer on the modalities of multi-genes panel analyses in hereditary predispositions to tumors of the digestive tract.

Eur J Med Genet 2020 Dec 8;63(12):104080. Epub 2020 Oct 8.

Institut Paoli-Calmettes, Department of Clinical Cancer Genetics, Aix Marseille Univ, INSERM, IRD, SESSTIM, Marseille, France.

In case of suspected hereditary predisposition to digestive cancers, next-generation sequencing can analyze simultaneously several genes associated with an increased risk of developing these tumors. Thus, "Gastro Intestinal" (GI) gene panels are commonly used in French molecular genetic laboratories. Lack of international recommendations led to disparities in the composition of these panels and in the management of patients. To harmonize practices, the Genetics and Cancer Group (GGC)-Unicancer set up a working group who carried out a review of the literature for 31 genes of interest in this context and established a list of genes for which the estimated risks associated with pathogenic variant seemed sufficiently reliable and high for clinical use. Pancreatic cancer susceptibility genes have been excluded. This expertise defined a panel of 14 genes of confirmed clinical interest and relevant for genetic counseling: APC, BMPR1A, CDH1, EPCAM, MLH1, MSH2, MSH6, MUTYH, PMS2, POLD1, POLE, PTEN, SMAD4 and STK11. The reasons for the exclusion of the others 23 genes have been discussed. The paucity of estimates of the associated tumor risks led to the exclusion of genes, in particular CTNNA1, MSH3 and NTHL1, despite their implication in the molecular pathways involved in the pathophysiology of GI cancers. A regular update of the literature is planned to up-grade this panel of genes in case of new data on candidate genes. Genetic and epidemiological studies and international collaborations are needed to better estimate the risks associated with the pathogenic variants of these genes either selected or not in the current panel.
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http://dx.doi.org/10.1016/j.ejmg.2020.104080DOI Listing
December 2020

Polygenic risk scores and breast and epithelial ovarian cancer risks for carriers of BRCA1 and BRCA2 pathogenic variants.

Genet Med 2020 10 15;22(10):1653-1666. Epub 2020 Jul 15.

Royal Devon & Exeter Hospital, Department of Clinical Genetics, Exeter, UK.

Purpose: We assessed the associations between population-based polygenic risk scores (PRS) for breast (BC) or epithelial ovarian cancer (EOC) with cancer risks for BRCA1 and BRCA2 pathogenic variant carriers.

Methods: Retrospective cohort data on 18,935 BRCA1 and 12,339 BRCA2 female pathogenic variant carriers of European ancestry were available. Three versions of a 313 single-nucleotide polymorphism (SNP) BC PRS were evaluated based on whether they predict overall, estrogen receptor (ER)-negative, or ER-positive BC, and two PRS for overall or high-grade serous EOC. Associations were validated in a prospective cohort.

Results: The ER-negative PRS showed the strongest association with BC risk for BRCA1 carriers (hazard ratio [HR] per standard deviation = 1.29 [95% CI 1.25-1.33], P = 3×10). For BRCA2, the strongest association was with overall BC PRS (HR = 1.31 [95% CI 1.27-1.36], P = 7×10). HR estimates decreased significantly with age and there was evidence for differences in associations by predicted variant effects on protein expression. The HR estimates were smaller than general population estimates. The high-grade serous PRS yielded the strongest associations with EOC risk for BRCA1 (HR = 1.32 [95% CI 1.25-1.40], P = 3×10) and BRCA2 (HR = 1.44 [95% CI 1.30-1.60], P = 4×10) carriers. The associations in the prospective cohort were similar.

Conclusion: Population-based PRS are strongly associated with BC and EOC risks for BRCA1/2 carriers and predict substantial absolute risk differences for women at PRS distribution extremes.
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http://dx.doi.org/10.1038/s41436-020-0862-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7521995PMC
October 2020

How and when to refer patients for oncogenetic counseling in the era of PARP inhibitors.

Ther Adv Med Oncol 2020 28;12:1758835919897530. Epub 2020 Feb 28.

Oncology Department, Centre François Baclesse, Caen, France.

Poly(ADP-ribose)polymerase (PARP) inhibitors are targeted therapy for cancers with homologous repair deficiency (HRD). They were first approved for ovarian cancer and have changed current treatment strategies. They have also demonstrated efficacy in HER2-negative metastatic breast cancer and advanced prostate cancer with or mutations. Patients with somatic and/or germline mutations benefit more from these treatments than other patients. Nowadays, the diagnosis of HRD is largely based on germline genetic testing, which is performed after an in-person genetic counseling session, even for patients without any family history of cancer. However, with the increasing number of PARP inhibitor indications across different tumor types, rapid access to oncogenetic consultations will become a challenge. To meet this demand, tumor genomic testing could be offered at initial diagnosis. Telephone counseling and other referral systems could replace in-person consultations for certain subgroups of patients deemed to have a low risk of harboring a germline mutation. This article reviews international guidelines for genetic counseling testing. We herein propose new care pathways for breast, prostate and ovarian cancers, including tumor genomic testing at initial diagnosis in order to help triage genetic counseling referrals.
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http://dx.doi.org/10.1177/1758835919897530DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7052467PMC
February 2020

Alcohol Consumption, Cigarette Smoking, and Risk of Breast Cancer for and Mutation Carriers: Results from The BRCA1 and BRCA2 Cohort Consortium.

Cancer Epidemiol Biomarkers Prev 2020 02 2;29(2):368-378. Epub 2019 Dec 2.

Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands.

Background: Tobacco smoking and alcohol consumption have been intensively studied in the general population to assess their effects on the risk of breast cancer, but very few studies have examined these effects in and mutation carriers. Given the high breast cancer risk for mutation carriers and the importance of and in DNA repair, better evidence on the associations of these lifestyle factors with breast cancer risk is essential.

Methods: Using a large international pooled cohort of and mutation carriers, we conducted retrospective (5,707 mutation carriers and 3,525 mutation carriers) and prospective (2,276 mutation carriers and 1,610 mutation carriers) analyses of alcohol and tobacco consumption using Cox proportional hazards models.

Results: For both and mutation carriers, none of the smoking-related variables was associated with breast cancer risk, except smoking for more than 5 years before a first full-term pregnancy (FFTP) when compared with parous women who never smoked. For mutation carriers, the HR from retrospective analysis (HR) was 1.19 [95% confidence interval (CI), 1.02-1.39] and the HR from prospective analysis (HR) was 1.36 (95% CI, 0.99-1.87). For mutation carriers, smoking for more than 5 years before an FFTP showed an association of a similar magnitude, but the confidence limits were wider (HR = 1.25; 95% CI, 1.01-1.55 and HR = 1.30; 95% CI, 0.83-2.01). For both carrier groups, alcohol consumption was not associated with breast cancer risk.

Conclusions: The finding that smoking during the prereproductive years increases breast cancer risk for mutation carriers warrants further investigation.

Impact: This is the largest prospective study of mutation carriers to assess these important risk factors.
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http://dx.doi.org/10.1158/1055-9965.EPI-19-0546DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7611162PMC
February 2020

Parental disclosure of positive mutation status to children 10 years after genetic testing.

Psychol Health Med 2020 07 11;25(6):756-766. Epub 2019 Sep 11.

Aix Marseille Univ, INSERM, IRD, SESSTIM, Sciences Economiques & Sociales de la Santé & Traitement de l'Information Médicale , Marseille, France.

The disclosure of genetic information is an important issue in cancer prevention. This study based on a French national cohort of mutation carriers (GENEPSO-PS cohort, ) aimed to assess the prevalence of parental disclosure of genetic information to children 10 years after genetic testing, with a focus on gender differences. Most participants (n = 193, 131 women) reported having children. A total of 72.0% of offspring had received genetic information (88.8% for adult offspring, p < .001), with no differences according to the gender of the mutation-carrying parent. While female carriers disclosed genetic information more often than male carriers (54.1% versus 38.3%, p = .029), they did so irrespective of the gender of their offspring. Moreover, female carriers who had developed incident cancer after genetic testing disclosed genetic information more frequently than unaffected female carriers (70.7% versus 48.5%, p = .005). A multivariate analysis confirmed the effects of both gender and cancer on disclosure to offspring. The same results were obtained when the analysis was restricted to adult offspring. This study reveals high rates of disclosure of positive mutation status to children 10 years after genetic testing, irrespective of the gender of the carrier/offspring. However, female carriers disclosed genetic information more frequently than male carriers.
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http://dx.doi.org/10.1080/13548506.2019.1659981DOI Listing
July 2020

Oral Contraceptive Use and Breast Cancer Risk: Retrospective and Prospective Analyses From a BRCA1 and BRCA2 Mutation Carrier Cohort Study.

JNCI Cancer Spectr 2018 Apr 28;2(2):pky023. Epub 2018 Jun 28.

Department of Pathology and Molecular Medicine, Juravinski Hospital and Cancer Centre, McMaster University, Hamilton, Ontario, Canada.

Background: For BRCA1 and BRCA2 mutation carriers, the association between oral contraceptive preparation (OCP) use and breast cancer (BC) risk is still unclear.

Methods: Breast camcer risk associations were estimated from OCP data on 6030 BRCA1 and 3809 BRCA2 mutation carriers using age-dependent Cox regression, stratified by study and birth cohort. Prospective, left-truncated retrospective and full-cohort retrospective analyses were performed.

Results: For BRCA1 mutation carriers, OCP use was not associated with BC risk in prospective analyses (hazard ratio [HR] = 1.08, 95% confidence interval [CI] = 0.75 to 1.56), but in the left-truncated and full-cohort retrospective analyses, risks were increased by 26% (95% CI = 6% to 51%) and 39% (95% CI = 23% to 58%), respectively. For BRCA2 mutation carriers, OCP use was associated with BC risk in prospective analyses (HR = 1.75, 95% CI = 1.03 to 2.97), but retrospective analyses were inconsistent (left-truncated: HR = 1.06, 95% CI = 0.85 to 1.33; full cohort: HR = 1.52, 95% CI = 1.28 to 1.81). There was evidence of increasing risk with duration of use, especially before the first full-term pregnancy (BRCA1: both retrospective analyses, < .001 and = .001, respectively; BRCA2: full retrospective analysis, = .002).

Conclusions: Prospective analyses did not show that past use of OCP is associated with an increased BC risk for BRCA1 mutation carriers in young middle-aged women (40-50 years). For BRCA2 mutation carriers, a causal association is also not likely at those ages. Findings between retrospective and prospective analyses were inconsistent and could be due to survival bias or a true association for younger women who were underrepresented in the prospective cohort. Given the uncertain safety of long-term OCP use for BRCA1/2 mutation carriers, indications other than contraception should be avoided and nonhormonal contraceptive methods should be discussed.
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http://dx.doi.org/10.1093/jncics/pky023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6649757PMC
April 2018

Uptake of genetic counseling among adult children of BRCA1/2 mutation carriers in France.

Psychooncology 2019 09 17;28(9):1894-1900. Epub 2019 Jul 17.

Aix-Marseille Univ, INSERM, IRD, SESSTIM, Sciences Economiques & Sociales de la Santé & Traitement de l'Information Médicale, Marseille, France.

Objective: Genetic counseling in at-risk families is known to improve cancer prevention. Our study aimed to determine the rate of uptake of genetic counseling among adult children of BRCA1/2 mutation carriers and to identify the potential psychosocial factors associated with uptake of genetic counseling.

Methods: A self-reported questionnaire was mailed to 328 BRCA1/2 mutation carriers 10 years after BRCA1/2 test disclosure. Of the 233 carriers who returned the questionnaire (response rate = 71%), 135 reported having children over age 18 years and were therefore included in the analysis. Generalized estimating equations models were used to identify the factors associated with uptake of genetic counseling among adult children of mutation carriers.

Results: Data were gathered for a total of 296 children (46% male, 54% female). The vast majority were informed about the familial mutation (90.9%) and 113 (38%; 95% CI, 32%-44%) underwent genetic counseling. This percentage exceeded 80% in women over 40 years. In the multivariate model, female sex, advanced age, mutation in the father, diagnosis of cancer in the mutation-carrying parent after genetic testing, and good family relationships were all factors associated with higher uptake of genetic counseling.

Conclusions: Adult children of BRCA1/2 mutation carriers in France do not undergo genetic counseling sufficiently often. Further studies should be conducted on the psychosocial factors that hinder the uptake of genetic counseling among adult children of BRCA1/2 mutation carriers.
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http://dx.doi.org/10.1002/pon.5169DOI Listing
September 2019

Familial breast cancer and DNA repair genes: Insights into known and novel susceptibility genes from the GENESIS study, and implications for multigene panel testing.

Int J Cancer 2019 04 13;144(8):1962-1974. Epub 2018 Nov 13.

Institut Bergonié, Bordeaux, France.

Pathogenic variants in BRCA1 and BRCA2 only explain the underlying genetic cause of about 10% of hereditary breast and ovarian cancer families. Because of cost-effectiveness, multigene panel testing is often performed even if the clinical utility of testing most of the genes remains questionable. The purpose of our study was to assess the contribution of rare, deleterious-predicted variants in DNA repair genes in familial breast cancer (BC) in a well-characterized and homogeneous population. We analyzed 113 DNA repair genes selected from either an exome sequencing or a candidate gene approach in the GENESIS study, which includes familial BC cases with no BRCA1 or BRCA2 mutation and having a sister with BC (N = 1,207), and general population controls (N = 1,199). Sequencing data were filtered for rare loss-of-function variants (LoF) and likely deleterious missense variants (MV). We confirmed associations between LoF and MV in PALB2, ATM and CHEK2 and BC occurrence. We also identified for the first time associations between FANCI, MAST1, POLH and RTEL1 and BC susceptibility. Unlike other associated genes, carriers of an ATM LoF had a significantly higher risk of developing BC than carriers of an ATM MV (OR = 17.4 vs. OR = 1.6; p = 0.002). Hence, our approach allowed us to specify BC relative risks associated with deleterious-predicted variants in PALB2, ATM and CHEK2 and to add MAST1, POLH, RTEL1 and FANCI to the list of DNA repair genes possibly involved in BC susceptibility. We also highlight that different types of variants within the same gene can lead to different risk estimates.
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http://dx.doi.org/10.1002/ijc.31921DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6587727PMC
April 2019

[The French Genetic and Cancer Consortium guidelines for multigene panel analysis in hereditary breast and ovarian cancer predisposition].

Bull Cancer 2018 Oct 27;105(10):907-917. Epub 2018 Sep 27.

Institut Paoli-Calmettes, oncogénétique clinique, département d'anticipation et de suivi des cancers, 232, boulevard Sainte-Marguerite, 13009 Marseille, France; Aix-Marseille université, Inserm, IRD, SESSTIM, 13000 Marseille, France.

Introduction: Next generation sequencing allows the simultaneous analysis of large panel of genes for families or individuals with a strong suspicion of hereditary breast and/or ovarian cancer (HBOC). Because of lack of guidelines, several panels of genes potentially involved in HBOC were designed, with large disparities not only in their composition but also in medical care offered to mutation carriers. Then, homogenization in practices is needed.

Methods: The French Genetic and Cancer Group (GGC) - Unicancer conducted an exhaustive bibliographic work on 18 genes of interest. Only publications with unbiased risk estimates were retained.

Results: The expertise of each 18 genes was based on clinical utility criteria, i.e. a relative risk of cancer of 4 and more, available medical tools for screening and prevention of mutation carriers, and pre-symptomatic genetic tests for relatives. Finally, 13 genes were selected to be included in a HBOC diagnosis gene panel: BRCA1, BRCA2, PALB2, TP53, CDH1, PTEN, RAD51C, RAD51D, MLH1, MSH2, MSH6, PMS2, EPCAM. The reasons for excluding NBN, RAD51B, CHEK2, STK11, ATM, BARD1, BRIP1 from the HBOC diagnosis panel are presented. Screening, prevention and genetic counselling guidelines were detailed for each of the 18 genes.

Discussion: Due to the rapid increase in knowledge, the GGC has planned a yearly update of the bibliography to take into account new findings. Furthermore, genetic-epidemiological studies are being initiated to better estimate the cancer risk associated with genes which are not yet included in the HBOC diagnosis panel.
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http://dx.doi.org/10.1016/j.bulcan.2018.08.003DOI Listing
October 2018

Landscape of pathogenic variations in a panel of 34 genes and cancer risk estimation from 5131 HBOC families.

Genet Med 2018 12 10;20(12):1677-1686. Epub 2018 Jul 10.

Laboratory of Cancer Biology and Genetics, Comprehensive Cancer Center François Baclesse, Caen, France.

Purpose: Integration of gene panels in the diagnosis of hereditary breast and ovarian cancer (HBOC) requires a careful evaluation of the risk associated with pathogenic or likely pathogenic variants (PVs) detected in each gene. Here we analyzed 34 genes in 5131 suspected HBOC index cases by next-generation sequencing.

Methods: Using the Exome Aggregation Consortium data sets plus 571 individuals from the French Exome Project, we simulated the probability that an individual from the Exome Aggregation Consortium carries a PV and compared it to the estimated frequency within the HBOC population.

Results: Odds ratio conferred by PVs within BRCA1, BRCA2, PALB2, RAD51C, RAD51D, ATM, BRIP1, CHEK2, and MSH6 were estimated at 13.22 [10.01-17.22], 8.61 [6.78-10.82], 8.22 [4.91-13.05], 4.54 [2.55-7.48], 5.23 [1.46-13.17], 3.20 [2.14-4.53], 2.49 [1.42-3.97], 1.67 [1.18-2.27], and 2.50 [1.12-4.67], respectively. PVs within RAD51C, RAD51D, and BRIP1 were associated with ovarian cancer family history (OR = 11.36 [5.78-19.59], 12.44 [2.94-33.30] and 3.82 [1.66-7.11]). PALB2 PVs were associated with bilateral breast cancer (OR = 16.17 [5.48-34.10]) and BARD1 PVs with triple-negative breast cancer (OR = 11.27 [3.37-25.01]). Burden tests performed in both patients and the French Exome Project population confirmed the association of PVs of BRCA1, BRCA2, PALB2, and RAD51C with HBOC.

Conclusion: Our results validate the integration of PALB2, RAD51C, and RAD51D in the diagnosis of HBOC and suggest that the other genes are involved in an oligogenic determinism.
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http://dx.doi.org/10.1038/s41436-018-0005-9DOI Listing
December 2018

Morphology and genomic hallmarks of breast tumours developed by ATM deleterious variant carriers.

Breast Cancer Res 2018 04 17;20(1):28. Epub 2018 Apr 17.

Laboratoire de Diagnostic Génétique, UF1422 Oncogénétique Moléculaire, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.

Background: The ataxia telangiectasia mutated (ATM) gene is a moderate-risk breast cancer susceptibility gene; germline loss-of-function variants are found in up to 3% of hereditary breast and ovarian cancer (HBOC) families who undergo genetic testing. So far, no clear histopathological and molecular features of breast tumours occurring in ATM deleterious variant carriers have been described, but identification of an ATM-associated tumour signature may help in patient management.

Methods: To characterise hallmarks of ATM-associated tumours, we performed systematic pathology review of tumours from 21 participants from ataxia-telangiectasia families and 18 participants from HBOC families, as well as copy number profiling on a subset of 23 tumours. Morphology of ATM-associated tumours was compared with that of 599 patients with no BRCA1 and BRCA2 mutations from a hospital-based series, as well as with data from The Cancer Genome Atlas. Absolute copy number and loss of heterozygosity (LOH) profiles were obtained from the OncoScan SNP array. In addition, we performed whole-genome sequencing on four tumours from ATM loss-of-function variant carriers with available frozen material.

Results: We found that ATM-associated tumours belong mostly to the luminal B subtype, are tetraploid and show LOH at the ATM locus at 11q22-23. Unlike tumours in which BRCA1 or BRCA2 is inactivated, tumours arising in ATM deleterious variant carriers are not associated with increased large-scale genomic instability as measured by the large-scale state transitions signature. Losses at 13q14.11-q14.3, 17p13.2-p12, 21p11.2-p11.1 and 22q11.23 were observed. Somatic alterations at these loci may therefore represent biomarkers for ATM testing and harbour driver mutations in potentially 'druggable' genes that would allow patients to be directed towards tailored therapeutic strategies.

Conclusions: Although ATM is involved in the DNA damage response, ATM-associated tumours are distinct from BRCA1-associated tumours in terms of morphological characteristics and genomic alterations, and they are also distinguishable from sporadic breast tumours, thus opening up the possibility to identify ATM variant carriers outside the ataxia-telangiectasia disorder and direct them towards effective cancer risk management and therapeutic strategies.
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http://dx.doi.org/10.1186/s13058-018-0951-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5905168PMC
April 2018

Contribution of germline deleterious variants in the RAD51 paralogs to breast and ovarian cancers.

Eur J Hum Genet 2017 12 8;25(12):1345-1353. Epub 2017 Nov 8.

Department of Tumour Biology, Institut Curie, Paris, 75005, France.

RAD51 paralogs (RAD51B, RAD51C, RAD51D, XRCC2, and XRCC3) have recently been involved in breast and ovarian cancer predisposition: RAD51B, RAD51C, and RAD51D in ovarian cancer, RAD51B and XRCC2 in breast cancer. The aim of this study was to estimate the contribution of deleterious variants in the five RAD51 paralogs to breast and ovarian cancers. The five RAD51 paralog genes were analyzed by next-generation sequencing technologies in germline DNA from 2649 consecutive patients diagnosed with breast and/or ovarian cancer. Twenty-one different deleterious variants were identified in the RAD51 paralogs in 30 patients: RAD51B (n = 4), RAD51C (n = 12), RAD51D (n = 7), XRCC2 (n = 2), and XRCC3 (n = 5). The overall deleterious variant rate was 1.13% (95% confidence interval (CI): 0.72-1.55%) (30/2649), including 15 variants in breast cancer only cases (15/2063; 0.73% (95% CI: 0.34-1.11%)) and 15 variants in cases with at least one ovarian cancer (15/570; 2.63% (95% CI: 1.24-4.02%)). This study is the first evaluation of the five RAD51 paralogs in breast and ovarian cancer predisposition and it demonstrates that deleterious variants can be present in breast cancer only cases. Moreover, this is the first time that XRCC3 deleterious variants have been identified in breast and ovarian cancer cases.
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http://dx.doi.org/10.1038/s41431-017-0021-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5865182PMC
December 2017

Cost-effectiveness evaluation of pre-counseling telephone interviews before face-to-face genetic counseling in cancer genetics.

Fam Cancer 2018 07;17(3):451-457

Department of Genetics, Rouen University Hospital, Normandy Centre for Genomic and Personalized Medicine, 76000, Rouen, France.

One of the main challenges in cancer genetics is responding to the exponential demand for genetic counseling, especially in patients with breast and/or ovarian cancer. To address this demand, we have set up a new procedure, based on pre-genetic counseling telephone interviews (PTI) followed by routing of patients: D1, a PTI is scheduled within 14 days; D7-D14, genetic counselors perform a 20 min PTI in order to establish a pre-genetic counseling file, by collecting personal and family medical history via a structured questionnaire and; D10-17, routing: pre-genetic counseling appointment files are analyzed by a cancer geneticist with 3 possible conclusions: (a) priority face-to-face genetic counseling (FTFGC) appointment with a cancer geneticist, if the genetic test results have an immediate therapeutic impact; (b) non-priority FTFGC with a genetic counselor, or (c) no FTFGC required or substitution by a more appropriate index case. In the context of breast and/or ovarian cancer, 1012 patients received PTIs, 39.1% of which did not lead to FTFGC. The mean delay for non-priority FTFGC was maintained at 18 weeks and priority FTFGC appointments were guaranteed within 8 weeks. The required resources for 1012 patients was estimated at 0.12 FTE secretaries, 0.62 FTE genetic counselors and 0.08 FTE cancer geneticists and the procedure was shown to be cost-effective. This new procedure allows the suppression of up to 1/3 of appointments, guarantees priority for appointments with therapeutic impact and optimizes the interaction and breakdown of tasks between genetic counselors and cancer geneticists.
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http://dx.doi.org/10.1007/s10689-017-0049-zDOI Listing
July 2018

Telomere length, ATM mutation status and cancer risk in Ataxia-Telangiectasia families.

Carcinogenesis 2017 10;38(10):994-1003

INSERM, U900, Paris, France.

Recent studies have linked constitutive telomere length (TL) to aging-related diseases including cancer at different sites. ATM participates in the signaling of telomere erosion, and inherited mutations in ATM have been associated with increased risk of cancer, particularly breast cancer. The goal of this study was to investigate whether carriage of an ATM mutation and TL interplay to modify cancer risk in ataxia-telangiectasia (A-T) families.The study population consisted of 284 heterozygous ATM mutation carriers (HetAT) and 174 non-carriers (non-HetAT) from 103 A-T families. Forty-eight HetAT and 14 non-HetAT individuals had cancer, among them 25 HetAT and 6 non-HetAT were diagnosed after blood sample collection. We measured mean TL using a quantitative PCR assay and genotyped seven single-nucleotide polymorphisms (SNPs) recurrently associated with TL in large population-based studies.HetAT individuals were at increased risk of cancer (OR = 2.3, 95%CI = 1.2-4.4, P = 0.01), and particularly of breast cancer for women (OR = 2.9, 95%CI = 1.2-7.1, P = 0.02), in comparison to their non-HetAT relatives. HetAT individuals had longer telomeres than non-HetAT individuals (P = 0.0008) but TL was not associated with cancer risk, and no significant interaction was observed between ATM mutation status and TL. Furthermore, rs9257445 (ZNF311) was associated with TL in HetAT subjects and rs6060627 (BCL2L1) modified cancer risk in HetAT and non-HetAT women.Our findings suggest that carriage of an ATM mutation impacts on the age-related TL shortening and that TL per se is not related to cancer risk in ATM carriers. TL measurement alone is not a good marker for predicting cancer risk in A-T families.
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http://dx.doi.org/10.1093/carcin/bgx074DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5862273PMC
October 2017

Risks of Breast, Ovarian, and Contralateral Breast Cancer for BRCA1 and BRCA2 Mutation Carriers.

JAMA 2017 06;317(23):2402-2416

Unité de Prévention et d'Epidémiologie Génétique, Centre Léon Bérard, Lyon, France.

Importance: The clinical management of BRCA1 and BRCA2 mutation carriers requires accurate, prospective cancer risk estimates.

Objectives: To estimate age-specific risks of breast, ovarian, and contralateral breast cancer for mutation carriers and to evaluate risk modification by family cancer history and mutation location.

Design, Setting, And Participants: Prospective cohort study of 6036 BRCA1 and 3820 BRCA2 female carriers (5046 unaffected and 4810 with breast or ovarian cancer or both at baseline) recruited in 1997-2011 through the International BRCA1/2 Carrier Cohort Study, the Breast Cancer Family Registry and the Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer, with ascertainment through family clinics (94%) and population-based studies (6%). The majority were from large national studies in the United Kingdom (EMBRACE), the Netherlands (HEBON), and France (GENEPSO). Follow-up ended December 2013; median follow-up was 5 years.

Exposures: BRCA1/2 mutations, family cancer history, and mutation location.

Main Outcomes And Measures: Annual incidences, standardized incidence ratios, and cumulative risks of breast, ovarian, and contralateral breast cancer.

Results: Among 3886 women (median age, 38 years; interquartile range [IQR], 30-46 years) eligible for the breast cancer analysis, 5066 women (median age, 38 years; IQR, 31-47 years) eligible for the ovarian cancer analysis, and 2213 women (median age, 47 years; IQR, 40-55 years) eligible for the contralateral breast cancer analysis, 426 were diagnosed with breast cancer, 109 with ovarian cancer, and 245 with contralateral breast cancer during follow-up. The cumulative breast cancer risk to age 80 years was 72% (95% CI, 65%-79%) for BRCA1 and 69% (95% CI, 61%-77%) for BRCA2 carriers. Breast cancer incidences increased rapidly in early adulthood until ages 30 to 40 years for BRCA1 and until ages 40 to 50 years for BRCA2 carriers, then remained at a similar, constant incidence (20-30 per 1000 person-years) until age 80 years. The cumulative ovarian cancer risk to age 80 years was 44% (95% CI, 36%-53%) for BRCA1 and 17% (95% CI, 11%-25%) for BRCA2 carriers. For contralateral breast cancer, the cumulative risk 20 years after breast cancer diagnosis was 40% (95% CI, 35%-45%) for BRCA1 and 26% (95% CI, 20%-33%) for BRCA2 carriers (hazard ratio [HR] for comparing BRCA2 vs BRCA1, 0.62; 95% CI, 0.47-0.82; P=.001 for difference). Breast cancer risk increased with increasing number of first- and second-degree relatives diagnosed as having breast cancer for both BRCA1 (HR for ≥2 vs 0 affected relatives, 1.99; 95% CI, 1.41-2.82; P<.001 for trend) and BRCA2 carriers (HR, 1.91; 95% CI, 1.08-3.37; P=.02 for trend). Breast cancer risk was higher if mutations were located outside vs within the regions bounded by positions c.2282-c.4071 in BRCA1 (HR, 1.46; 95% CI, 1.11-1.93; P=.007) and c.2831-c.6401 in BRCA2 (HR, 1.93; 95% CI, 1.36-2.74; P<.001).

Conclusions And Relevance: These findings provide estimates of cancer risk based on BRCA1 and BRCA2 mutation carrier status using prospective data collection and demonstrate the potential importance of family history and mutation location in risk assessment.
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http://dx.doi.org/10.1001/jama.2017.7112DOI Listing
June 2017

Inheritance of deleterious mutations at both BRCA1 and BRCA2 in an international sample of 32,295 women.

Breast Cancer Res 2016 11 11;18(1):112. Epub 2016 Nov 11.

Genomic Medicine, Manchester Academic Health Sciences Centre, Institute of Human Development, Manchester University, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK.

Background: Most BRCA1 or BRCA2 mutation carriers have inherited a single (heterozygous) mutation. Transheterozygotes (TH) who have inherited deleterious mutations in both BRCA1 and BRCA2 are rare, and the consequences of transheterozygosity are poorly understood.

Methods: From 32,295 female BRCA1/2 mutation carriers, we identified 93 TH (0.3 %). "Cases" were defined as TH, and "controls" were single mutations at BRCA1 (SH1) or BRCA2 (SH2). Matched SH1 "controls" carried a BRCA1 mutation found in the TH "case". Matched SH2 "controls" carried a BRCA2 mutation found in the TH "case". After matching the TH carriers with SH1 or SH2, 91 TH were matched to 9316 SH1, and 89 TH were matched to 3370 SH2.

Results: The majority of TH (45.2 %) involved the three common Jewish mutations. TH were more likely than SH1 and SH2 women to have been ever diagnosed with breast cancer (BC; p = 0.002). TH were more likely to be diagnosed with ovarian cancer (OC) than SH2 (p = 0.017), but not SH1. Age at BC diagnosis was the same in TH vs. SH1 (p = 0.231), but was on average 4.5 years younger in TH than in SH2 (p < 0.001). BC in TH was more likely to be estrogen receptor (ER) positive (p = 0.010) or progesterone receptor (PR) positive (p = 0.013) than in SH1, but less likely to be ER positive (p < 0.001) or PR positive (p = 0.012) than SH2. Among 15 tumors from TH patients, there was no clear pattern of loss of heterozygosity (LOH) for BRCA1 or BRCA2 in either BC or OC.

Conclusions: Our observations suggest that clinical TH phenotypes resemble SH1. However, TH breast tumor marker characteristics are phenotypically intermediate to SH1 and SH2.
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http://dx.doi.org/10.1186/s13058-016-0768-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5106833PMC
November 2016

Association of breast cancer risk in BRCA1 and BRCA2 mutation carriers with genetic variants showing differential allelic expression: identification of a modifier of breast cancer risk at locus 11q22.3.

Breast Cancer Res Treat 2017 01 28;161(1):117-134. Epub 2016 Oct 28.

Center for Medical Genetics, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium.

Purpose: Cis-acting regulatory SNPs resulting in differential allelic expression (DAE) may, in part, explain the underlying phenotypic variation associated with many complex diseases. To investigate whether common variants associated with DAE were involved in breast cancer susceptibility among BRCA1 and BRCA2 mutation carriers, a list of 175 genes was developed based of their involvement in cancer-related pathways.

Methods: Using data from a genome-wide map of SNPs associated with allelic expression, we assessed the association of ~320 SNPs located in the vicinity of these genes with breast and ovarian cancer risks in 15,252 BRCA1 and 8211 BRCA2 mutation carriers ascertained from 54 studies participating in the Consortium of Investigators of Modifiers of BRCA1/2.

Results: We identified a region on 11q22.3 that is significantly associated with breast cancer risk in BRCA1 mutation carriers (most significant SNP rs228595 p = 7 × 10). This association was absent in BRCA2 carriers (p = 0.57). The 11q22.3 region notably encompasses genes such as ACAT1, NPAT, and ATM. Expression quantitative trait loci associations were observed in both normal breast and tumors across this region, namely for ACAT1, ATM, and other genes. In silico analysis revealed some overlap between top risk-associated SNPs and relevant biological features in mammary cell data, which suggests potential functional significance.

Conclusion: We identified 11q22.3 as a new modifier locus in BRCA1 carriers. Replication in larger studies using estrogen receptor (ER)-negative or triple-negative (i.e., ER-, progesterone receptor-, and HER2-negative) cases could therefore be helpful to confirm the association of this locus with breast cancer risk.
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http://dx.doi.org/10.1007/s10549-016-4018-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5222911PMC
January 2017

BRCA1 allele-specific expression in genetic predisposed breast/ovarian cancer.

Fam Cancer 2017 04;16(2):167-171

Laboratoire de Biologie et Génétique du Cancer - Centre Normand de Génomique Médicale et Médecine Personnalisée, Centre François Baclesse, 3 avenue du général Harris, 14076, Caen Cedex 05, France.

Germline allele specific expression (ASE), resulting in a lowered expression of one of the BRCA1 alleles, has been described as a possible predisposition marker in Hereditary Breast or Ovarian Cancer (HBOC), usable for molecular diagnosis in HBOC. The main objective of this prospective case-control study was to compare the proportion of ASE between controls without familial history of breast or ovarian cancer, and HBOC cases without BRCA1 or BRCA2 deleterious mutation. BRCA1 ASE evaluated on three SNPs among controls and HBOC patients without deleterious mutation were assessed by pyrosequencing. The allelic ratios and the proportion of ASE were compared between controls and cases using a Student's t test and a Fisher exact test, respectively. The linearity and reproducibility of the ASE dosage was demonstrated with R > 0.99 and a coefficient of variation below 10 %, and ASE was detected in two positive controls harbouring BRCA1 truncated mutations. In the heterozygote population, composed of 99/264 controls (37.5 %) and 96/227 patients (42.3 %), we detected a 5 % ASE without truncated mutations, in each population. We failed to detect any significant difference of ASE between controls and patients. So far, BRCA1 Allelic specific expression is not usable in routine diagnosis as a possible predisposition marker in HBOC patients except for the detection of truncated mutations.
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http://dx.doi.org/10.1007/s10689-016-9940-2DOI Listing
April 2017

GENESIS: a French national resource to study the missing heritability of breast cancer.

BMC Cancer 2016 Jan 12;16:13. Epub 2016 Jan 12.

Université Claude Bernard Lyon 1, Villeurbanne, France.

Background: Less than 20% of familial breast cancer patients who undergo genetic testing for BRCA1 and BRCA2 carry a pathogenic mutation in one of these two genes. The GENESIS (GENE SISter) study was designed to identify new breast cancer susceptibility genes in women attending cancer genetics clinics and with no BRCA1/2 mutation.

Methods: The study involved the French national network of family cancer clinics. It was based on enrichment in genetic factors of the recruited population through case selection relying on familial criteria, but also on the consideration of environmental factors and endophenotypes like mammary density or tumor characteristics to assess potential genetic heterogeneity. One of the initial aims of GENESIS was to recruit affected sibpairs. Siblings were eligible when index cases and at least one affected sister were diagnosed with infiltrating mammary or ductal adenocarcinoma, with no BRCA1/2 mutation. In addition, unrelated controls and unaffected sisters were recruited. The enrolment of patients, their relatives and their controls, the collection of the clinical, epidemiological, familial and biological data were centralized by a coordinating center.

Results: Inclusion of participants started in February 2007 and ended in December 2013. A total of 1721 index cases, 826 affected sisters, 599 unaffected sisters and 1419 controls were included. 98% of participants completed the epidemiological questionnaire, 97% provided a blood sample, and 76% were able to provide mammograms. Index cases were on average 59 years old at inclusion, were born in 1950, and were 49.7 years of age at breast cancer diagnosis. The mean age at diagnosis of affected sisters was slightly higher (51.4 years). The representativeness of the control group was verified.

Conclusions: The size of the study, the availability of biological specimens and the clinical data collection together with the detailed and complete epidemiological questionnaire make this a unique national resource for investigation of the missing heritability of breast cancer, by taking into account environmental and life style factors and stratifying data on endophenotypes to decrease genetic heterogeneity.
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http://dx.doi.org/10.1186/s12885-015-2028-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4711059PMC
January 2016

Mutation analysis of PALB2 gene in French breast cancer families.

Breast Cancer Res Treat 2015 Dec 12;154(3):463-71. Epub 2015 Nov 12.

Unité d'Oncologie Génétique, Centre Paul Strauss, Strasbourg, France.

Several population-based and family-based studies have demonstrated that germline mutations of the PALB2 gene (Partner and Localizer of BRCA2) are associated with an increased risk of breast cancer. Distinct mutation frequencies and spectrums have been described depending on the population studied. Here we describe the first complete PALB2 coding sequence screening in the French population. We screened the complete coding sequence and intron-exon boundaries of PALB2, using the EMMA technique, to assess the contribution of pathogenic mutations in a set of 835 familial breast cancer cases and 662 unrelated controls from the French national study GENESIS and the Paul Strauss Cancer Centre, all previously tested negative for BRCA1 and BRCA2 pathogenic mutations. Our analysis revealed the presence of four novel deleterious mutations: c.1186insT, c.1857delT and c.2850delC in three cases, c.3418dupT in one control. In addition, we identified two in-frame insertion/deletion, 19 missense substitutions (two of them predicted as pathogenic), 9 synonymous variants, 28 variants located in introns and 2 in UTRs, as well as frequent variants. Truncating PALB2 mutations were found in 0.36% of familial breast cancer cases, a frequency lower than the one detected in comparable studies in other populations (0.73-3.40%). This suggests a small but significant contribution of PALB2 mutations to the breast cancer susceptibility in the French population.
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http://dx.doi.org/10.1007/s10549-015-3625-7DOI Listing
December 2015

Targeted Sequencing of the Mitochondrial Genome of Women at High Risk of Breast Cancer without Detectable Mutations in BRCA1/2.

PLoS One 2015 25;10(9):e0136192. Epub 2015 Sep 25.

INSERM U1052, CNRS UMR5286, Université Lyon 1, Centre de Recherche en Cancérologie de Lyon, Lyon, France.

Breast Cancer is a complex multifactorial disease for which high-penetrance mutations have been identified. Approaches used to date have identified genomic features explaining about 50% of breast cancer heritability. A number of low- to medium penetrance alleles (per-allele odds ratio < 1.5 and 4.0, respectively) have been identified, suggesting that the remaining heritability is likely to be explained by the cumulative effect of such alleles and/or by rare high-penetrance alleles. Relatively few studies have specifically explored the mitochondrial genome for variants potentially implicated in breast cancer risk. For these reasons, we propose an exploration of the variability of the mitochondrial genome in individuals diagnosed with breast cancer, having a positive breast cancer family history but testing negative for BRCA1/2 pathogenic mutations. We sequenced the mitochondrial genome of 436 index breast cancer cases from the GENESIS study. As expected, no pathogenic genomic pattern common to the 436 women included in our study was observed. The mitochondrial genes MT-ATP6 and MT-CYB were observed to carry the highest number of variants in the study. The proteins encoded by these genes are involved in the structure of the mitochondrial respiration chain, and variants in these genes may impact reactive oxygen species production contributing to carcinogenesis. More functional and epidemiological studies are needed to further investigate to what extent variants identified may influence familial breast cancer risk.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0136192PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4583250PMC
May 2016

Clinical relevance of 8q23, 15q13 and 18q21 SNP genotyping to evaluate colorectal cancer risk.

Eur J Hum Genet 2016 Jan 15;24(1):99-105. Epub 2015 Apr 15.

Department of Genetics, University Hospital, Angers, France.

To determine if the at-risk single-nucleotide polymorphism (SNP) alleles for colorectal cancer (CRC) could contribute to clinical situations suggestive of an increased genetic risk for CRC, we performed a prospective national case-control study based on highly selected patients (CRC in two first-degree relatives, one before 61 years of age; or CRC diagnosed before 51 years of age; or multiple primary CRCs, the first before 61 years of age; exclusion of Lynch syndrome and polyposes) and controls without personal or familial history of CRC. SNPs were genotyped using SNaPshot, and statistical analyses were performed using Pearson's χ(2) test, Cochran-Armitage test of trend and logistic regression. We included 1029 patients and 350 controls. We confirmed the association of CRC risk with four SNPs, with odds ratio (OR) higher than previously reported: rs16892766 on 8q23.3 (OR: 1.88, 95% confidence interval (CI): 1.30-2.72; P=0.0007); rs4779584 on 15q13.3 (OR: 1.42, CI: 1.11-1.83; P=0.0061) and rs4939827 and rs58920878/Novel 1 on 18q21.1 (OR: 1.49, CI: 1.13-1.98; P=0.007 and OR: 1.49, CI: 1.14-1.95; P=0.0035). We found a significant (P<0.0001) cumulative effect of the at-risk alleles or genotypes with OR at 1.62 (CI: 1.10-2.37), 2.09 (CI: 1.43-3.07), 2.87 (CI: 1.76-4.70) and 3.88 (CI: 1.72-8.76) for 1, 2, 3 and at least 4 at-risk alleles, respectively, and OR at 1.71 (CI: 1.18-2.46), 2.29 (CI: 1.55-3.38) and 6.21 (CI: 2.67-14.42) for 1, 2 and 3 at-risk genotypes, respectively. Combination of SNPs may therefore explain a fraction of clinical situations suggestive of an increased risk for CRC.
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http://dx.doi.org/10.1038/ejhg.2015.72DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4795220PMC
January 2016

Assessing associations between the AURKA-HMMR-TPX2-TUBG1 functional module and breast cancer risk in BRCA1/2 mutation carriers.

PLoS One 2015 1;10(4):e0120020. Epub 2015 Apr 1.

Women's Cancer Program at the Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, California, United States of America.

While interplay between BRCA1 and AURKA-RHAMM-TPX2-TUBG1 regulates mammary epithelial polarization, common genetic variation in HMMR (gene product RHAMM) may be associated with risk of breast cancer in BRCA1 mutation carriers. Following on these observations, we further assessed the link between the AURKA-HMMR-TPX2-TUBG1 functional module and risk of breast cancer in BRCA1 or BRCA2 mutation carriers. Forty-one single nucleotide polymorphisms (SNPs) were genotyped in 15,252 BRCA1 and 8,211 BRCA2 mutation carriers and subsequently analyzed using a retrospective likelihood approach. The association of HMMR rs299290 with breast cancer risk in BRCA1 mutation carriers was confirmed: per-allele hazard ratio (HR) = 1.10, 95% confidence interval (CI) 1.04-1.15, p = 1.9 x 10(-4) (false discovery rate (FDR)-adjusted p = 0.043). Variation in CSTF1, located next to AURKA, was also found to be associated with breast cancer risk in BRCA2 mutation carriers: rs2426618 per-allele HR = 1.10, 95% CI 1.03-1.16, p = 0.005 (FDR-adjusted p = 0.045). Assessment of pairwise interactions provided suggestions (FDR-adjusted pinteraction values > 0.05) for deviations from the multiplicative model for rs299290 and CSTF1 rs6064391, and rs299290 and TUBG1 rs11649877 in both BRCA1 and BRCA2 mutation carriers. Following these suggestions, the expression of HMMR and AURKA or TUBG1 in sporadic breast tumors was found to potentially interact, influencing patients' survival. Together, the results of this study support the hypothesis of a causative link between altered function of AURKA-HMMR-TPX2-TUBG1 and breast carcinogenesis in BRCA1/2 mutation carriers.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0120020PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4382299PMC
December 2015

Breast Cancer Risk Associated with Estrogen Exposure and Truncating Mutation Location in BRCA1/2 Carriers.

Cancer Epidemiol Biomarkers Prev 2015 Apr 22;24(4):698-707. Epub 2015 Jan 22.

Institut Curie, Paris, France. INSERM, U900, Paris, France. Mines ParisTech, Fontainebleau, France.

Background: Mutations in BRCA1/2 confer a high risk of breast cancer, but literature values of this risk vary. A genotype-phenotype correlation has been found in both genes, and the effect of reproductive factors differs according to mutation location. Therefore, we hypothesize that such a variation may exist for other factors related to estrogen exposure.

Methods: We used a weighted Cox regression model to assess variation in breast cancer risk with these factors using location of mutation in homogeneous breast cancer risk region of BRCA1/2 in the GENEPSO study.

Results: We found that late age at menarche reduced breast cancer risk by 31% and that among BRCA1 carriers, a long or a short menstrual cycle increased risk (by 65% and 73%, respectively). Among premenopausal women, overweight was associated with a 45% decrease in risk whereas underweight was associated with an increased risk (HR, 2.40). A natural menopause, mainly after age 50, was associated with a high breast cancer risk (HR, 2.46), and a significant interaction between menopause status and the location of mutations was found leading up to 10% variation in absolute risk according to the age at menopause.

Conclusions: As observed in the general population, a late menarche, a long or a short menstrual cycle, over- or underweight, and being postmenopausal were associated with breast cancer risk in BRCA1/2 carriers. The association with the menopause was observed only when the mutation was located in the "high-risk" zones.

Impact: Taking into account modifier factors, location of mutation might be important for the clinical management of BRCA1/2 mutation carriers.
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http://dx.doi.org/10.1158/1055-9965.EPI-14-0884DOI Listing
April 2015

[Gliomas and BRCA genes mutations: fortuitous association or imputability?].

Bull Cancer 2014 Sep;101(9):795-802

CHU Pasteur, Fédération de neuro-oncologie, Neurologie, 30, voie Romaine, 06000 Nice, France.

BRCA is a tumor suppressor gene implicated in the major mechanisms of cellular stability in every type of cell. Its mutations are described in numerous cancers, mainly breast and ovarian in women. It was also found an increase of lifetime risk of pancreas, colon, prostate cancer or lymphoma in men carriers. We report the cases of two female patients aged 40 and 58-years-old female patients and one 35-years-old male patient, with brain or medullar gliomas, carriers of a germline mutation of BRCA gene. Those gliomas were particularly aggressive and were not responding to the standard treatment, with chemo and radiotherapy. The very unusual characteristics in location and evolutive profile of these central nervous system tumors raise the question of a genetical underlying mechanism, maybe linked to the BRCA gene mutation that carry these patients. In addition, a non-fortuitous association between germline mutation of BRCA and occurrence of a glioma can be evoked according to the embryological, epidemiological and biomolecular findings noted in the literature. Other clinical and experimental studies are necessary to precise the physiopathological link existing between BRCA mutations and the occurrence of a glioma; this could have therapeutical and clinical implications in the future.
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http://dx.doi.org/10.1684/bdc.2014.1952DOI Listing
September 2014
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