[Show abstract][Hide abstract] ABSTRACT: Inherited mutations in BRCA1 or BRCA2 (BRCA1/2) confer very high risk of breast and ovarian cancers. Genetic testing and counseling can reduce risk and death from these cancers if appropriate preventive strategies are applied, including risk-reducing salpingo-oophorectomy (RRSO) or risk-reducing mastectomy (RRM). However, some women who might benefit from these interventions do not take full advantage of them. We evaluated RRSO and RRM use in a prospective cohort of 1,499 women with inherited BRCA1/2 mutations from 20 centers who enrolled in the study without prior cancer or RRSO or RRM and were followed forward for the occurrence of these events. We estimated the age-specific usage of RRSO/RRM in this cohort using Kaplan-Meier analyses. Use of RRSO was 45 % for BRCA1 and 34 % for BRCA2 by age 40, and 86 % for BRCA1 and 71 % for BRCA2 by age 50. RRM usage was estimated to be 46 % by age 70 in both BRCA1 and BRCA2 carriers. BRCA1 mutation carriers underwent RRSO more frequently than BRCA2 mutation carriers overall, but the uptake of RRSO in BRCA2 was similar after mutation testing and in women born since 1960. RRM uptake was similar for both BRCA1 and BRCA2. Childbearing influenced the use of RRSO and RRM in both BRCA1 and BRCA2. Uptake of RRSO is high, but some women are still diagnosed with ovarian cancer before undergoing RRSO. This suggests that research is needed to understand the optimal timing of RRSO to maximize risk reduction and limit potential adverse consequences of RRSO.
Breast Cancer Research and Treatment 10/2014; · 4.47 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Recent genome wide association studies (GWAS) and subsequent meta-analyses have identified over 25 SNPs at 18 loci, together accounting for >15% of the genetic susceptibility to testicular germ cell tumour (TGCT). To identify further common SNPs associated with TGCT here we report a three-stage experiment, involving 4,098 cases and 18,972 controls. Stage 1 comprised previously published GWAS analysis of 307,291 SNPs in 986 cases and 4,946 controls. In stage 2 we used previously published customised Illumina iSelect genotyping array (iCOGs) data across 694 SNPs in 1,064 cases and 10,082 controls. Here we report new genotyping of eight SNPs showing some evidence of association in combined analysis of stage 1 and stage 2 in an additional 2,048 cases of TGCT and 3,944 controls (stage 3). Through fixed effects meta-analysis across 3 stages, we identified a novel locus at 3q25.31 (rs1510272) demonstrating association with TGCT (per-allele odds ratio (OR)=1.16, 95% confidence interval (CI)=1.06-1.27; P=1.2 x 10(-9)).
Human Molecular Genetics 10/2014; · 7.69 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Long interspersed nuclear element-1 (L1) retrotransposons are mobile repetitive elements that are abundant in the human genome. L1 elements propagate through RNA intermediates. In the germ line, neighboring, nonrepetitive sequences are occasionally mobilized by the L1 machinery, a process called 3' transduction. Because 3' transductions are potentially mutagenic, we explored the extent to which they occur somatically during tumorigenesis. Studying cancer genomes from 244 patients, we found that tumors from 53% of the patients had somatic retrotranspositions, of which 24% were 3' transductions. Fingerprinting of donor L1s revealed that a handful of source L1 elements in a tumor can spawn from tens to hundreds of 3' transductions, which can themselves seed further retrotranspositions. The activity of individual L1 elements fluctuated during tumor evolution and correlated with L1 promoter hypomethylation. The 3' transductions disseminated genes, exons, and regulatory elements to new locations, most often to heterochromatic regions of the genome.
[Show abstract][Hide abstract] ABSTRACT: Prostate cancer (PrCa) is the most commonly diagnosed cancer in the male UK population, with over 40,000 new cases per year. PrCa has a complex, polygenic predisposition, due to rare variants such as BRCA and common variants such as single nucleotide polymorphisms (SNPs). With the introduction of genome-wide association studies, 78 susceptibility loci (SNPs) associated with PrCa risk have been identified. Genetic profiling could risk-stratify a population, leading to the discovery of a higher proportion of clinically significant disease and a reduction in the morbidity related to age-based prostate-specific antigen screening. Based on the combined risk of the 78 SNPs identified so far, the top 1% of the risk distribution has a 4.7-times higher risk of developing PrCa compared with the average of the general population.
[Show abstract][Hide abstract] ABSTRACT: Background: Only a minority of the genetic component of prostate cancer (PrCa) risk has been explained. Some observed associations of single nucleotide polymorphisms (SNPs) with PrCa might arise from associations of these SNPs with circulating prostate specific antigen (PSA) because PSA values are used to select controls. Methods: We undertook a genome-wide association study (GWAS) of screen detected PrCa (ProtecT 1146 cases and 1804 controls); meta-analysed the results with those from the previously published UK Genetic Prostate Cancer Study (1854 cases and 1437 controls); investigated associations of SNPs with PrCa using either 'low' (PSA ≤0.5ng/ml) or 'high' (PSA ≥3ng/ml, biopsy negative) PSA controls; and investigated associations of SNPs with PSA. Results: The ProtecT GWAS confirmed previously reported associations of PrCa at 3 loci: 10q11.23, 17q24.3 and 19q13.33. The meta-analysis confirmed associations of PrCa with SNPs near 4 previously identified loci (8q24.21,10q11.23, 17q24.3 and 19q13.33). When comparing PrCa cases with low PSA controls, alleles at genetic markers rs1512268, rs445114, rs10788160, rs11199874, rs17632542, rs266849 and rs2735839 were associated with an increased risk of PrCa, but the effect-estimates were attenuated to the null when using high PSA controls (p for heterogeneity in effect-estimates<0.04). We found a novel inverse association of rs9311171-T with circulating PSA. Conclusions: Differences in effect estimates for PrCa observed when comparing low vs. high PSA controls, may be explained by associations of these SNPs with PSA. Impact: These findings highlight the need for inferences from genetic studies of PrCa risk to carefully consider the influence of control selection criteria.
Cancer Epidemiology Biomarkers & Prevention 04/2014; · 4.56 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background:Telomere length has been linked to risk of common diseases, including cancer, and has previously been proposed as a biomarker for cancer risk. Germline BRCA1 and BRCA2 mutations predispose to breast, ovarian and other cancer types. Methods:We investigated telomere length in BRCA mutation carriers and their non-carrier relatives and further examined whether telomere length is a modifier of cancer risk in mutation carriers. We measured mean telomere length in DNA extracted from whole blood using high-throughput Q-PCR. Participants were from the EMBRACE study in the UK and Eire (n=4,822) and comprised BRCA1 (n=1,628) and BRCA2 (n=1,506) mutation carriers and their non-carrier relatives (n=1,688). Results:We find no significant evidence that mean telomere length is associated with breast or ovarian cancer risk in BRCA mutation carriers. However, we find mutation carriers to have longer mean telomere length than their non-carrier relatives (all carriers vs. non-carriers, P-trend=0.0018), particularly in families with BRCA2 mutations (BRCA2 mutation carriers vs. all non-carriers, P-trend=0.0016). Conclusions:Our main and unexpected finding is that BRCA mutation carriers (regardless of cancer status) have longer telomeres than their non-mutation carrier, non-cancer-affected relatives. The longer telomere length in BRCA2 mutation carriers is consistent with its role in DNA damage response. Overall, it appears that increased telomere length may be a consequence of these mutations, but is not itself directly related to the increased cancer risk in carriers. Impact:Our findings lend little support to the hypothesis that short mean telomere length predisposes to cancer.
Cancer Epidemiology Biomarkers & Prevention 03/2014; · 4.56 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to determine whether BRCA1 and BRCA2 mutation carriers have different baseline CA125 levels compared with non-carriers, and whether a significant difference in pre- and post-operative CA125 levels exists in BRCA mutation carriers undergoing risk-reducing bilateral salpingo-oophorectomy (RRBSO). The study also considered whether CA125 measurements should continue in unaffected BRCA mutation carriers after RRBSO. 383 Eligible women were identified through retrospective review of the BRCA Carrier Clinic at The Royal Marsden NHS Foundation Trust, London, UK. These women all had CA125 levels measured as they were either a carrier or at risk of a BRCA1 or BRCA2 mutation. Of these, 76 went on to have a negative predictive test for their familial mutation and so are classed as 'non-carriers'. 133 BRCA1 and 87 BRCA2 carriers had RRBSO, with a further 26 BRCA1 carriers, 28 BRCA2 carriers and one non-carrier developing ovarian cancer. The remaining 21 BRCA1 and 28 BRCA2 carriers did not have RRBSO or develop ovarian cancer in the time of study follow-up. CA125 levels were measured as surveillance or as part of pre-RRBSO care. CA125 measurement post-RRBSO was continued in 48 BRCA1 and 40 BRCA2 carriers. In 154 BRCA1 mutation carriers, the median baseline (i.e. before RRBSO and with no clinical signs of ovarian cancer) CA125 level was 9.0 U/ml (range 2-78) and was 10.0 U/ml (range 1-43) in 115 BRCA2 mutation carriers. When compared with the 75 non-carriers (median baseline CA125 10.0 U/ml; range 2-52), there was no significant difference between the BRCA1, BRCA2 and non-carrier groups. There was a significant reduction in CA125 from pre- to post-RRBSO in 48 BRCA1 carriers (p = 0.04) but no significant difference in 40 BRCA2 mutation carriers (p = 0.5). Out of a total of 220 mutation carriers who underwent RRBSO, two had an incidental ovarian cancer found on histopathology and another developed primary peritoneal cancer during the follow-up period. Our study is the first to compare initial serum CA125 levels in BRCA1 and BRCA2 mutation carriers with those of non-carriers. Our study found no significant difference between the three groups. A drop in CA125 levels after RRBSO in BRCA1 carriers supports the finding of earlier studies, but differed in that the fall was not seen in BRCA2 carriers. The finding of only one case of post-operative peritoneal cancer in 220 carriers undergoing RRBSO supports the discontinuation of post-RRBSO serum CA125 monitoring in BRCA mutation carriers.
[Show abstract][Hide abstract] ABSTRACT: Worldwide, familial and epidemiological studies have generated considerable evidence of an inherited component to prostate cancer. Indeed, rare highly penetrant genetic mutations have been implicated. Genome-wide association studies (GWAS) have also identified 76 susceptibility loci associated with prostate cancer risk, which occur commonly but are of low penetrance. However, these mutations interact multiplicatively, which can result in substantially increased risk. Currently, approximately 30% of the familial risk is due to such variants. Evaluating the functional aspects of these variants would contribute to our understanding of prostate cancer aetiology and would enable population risk stratification for screening. Furthermore, understanding the genetic risks of prostate cancer might inform predictions of treatment responses and toxicities, with the goal of personalized therapy. However, risk modelling and clinical translational research are needed before we can translate risk profiles generated from these variants into use in the clinical setting for targeted screening and treatment.
[Show abstract][Hide abstract] ABSTRACT: Controversy surrounds the use of PSA as a biomarker for prostate cancer detection, leaving an unmet need for a novel biomarker in this setting; urinary EN2 may identify individuals with clinically relevant prostate cancer. Male BRCA1 and BRCA2 mutation carriers are at increased risk of clinically significant prostate cancer and may benefit from screening. Urine samples from 413 BRCA1 and BRCA2 mutation carriers and controls were evaluated. Subjects underwent annual PSA screening with diagnostic biopsy triggered by PSA > 3.0 ng/ml; 21 men were diagnosed with prostate cancer. Urinary EN2 levels were measured by ELISA and had a sensitivity of 66.7% and specificity of 89.3% for cancer detection. There was no statistically significant difference in EN2 levels according to genetic status or Gleason score. Urinary EN2 may be useful as a non-invasive early biomarker for prostate cancer detection in genetically high-risk individuals.
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND:
Reliable estimates of cancer risk are critical for guiding management of BRCA1 and BRCA2 mutation carriers. The aims of this study were to derive penetrance estimates for breast cancer, ovarian cancer, and contralateral breast cancer in a prospective series of mutation carriers and to assess how these risks are modified by common breast cancer susceptibility alleles.
Prospective cancer risks were estimated using a cohort of 978 BRCA1 and 909 BRCA2 carriers from the United Kingdom. Nine hundred eighty-eight women had no breast or ovarian cancer diagnosis at baseline, 1509 women were unaffected by ovarian cancer, and 651 had been diagnosed with unilateral breast cancer. Cumulative risks were obtained using Kaplan-Meier estimates. Associations between cancer risk and covariables of interest were evaluated using Cox regression. All statistical tests were two-sided.
The average cumulative risks by age 70 years for BRCA1 carriers were estimated to be 60% (95% confidence interval [CI] = 44% to 75%) for breast cancer, 59% (95% CI = 43% to 76%) for ovarian cancer, and 83% (95% CI = 69% to 94%) for contralateral breast cancer. For BRCA2 carriers, the corresponding risks were 55% (95% CI = 41% to 70%) for breast cancer, 16.5% (95% CI = 7.5% to 34%) for ovarian cancer, and 62% (95% CI = 44% to 79.5%) for contralateral breast cancer. BRCA2 carriers in the highest tertile of risk, defined by the joint genotype distribution of seven single nucleotide polymorphisms associated with breast cancer risk, were at statistically significantly higher risk of developing breast cancer than those in the lowest tertile (hazard ratio = 4.1, 95% CI = 1.2 to 14.5; P = .02).
Prospective risk estimates confirm that BRCA1 and BRCA2 carriers are at high risk of developing breast, ovarian, and contralateral breast cancer. Our results confirm findings from retrospective studies that common breast cancer susceptibility alleles in combination are predictive of breast cancer risk for BRCA2 carriers.
JNCI Journal of the National Cancer Institute 06/2013; 105(11):812. · 14.34 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background:To determine whether the alleles that influence type 2 diabetes risk and glycemic traits also influence prostate cancer risk. Methods:We used a multiple single nucleotide polymorphisms (SNP) genotypic risk score to assess the average effect of alleles that increase type 2 diabetes risk or worsen glycemic traits on risk of prostate cancer in 19,662 prostate cancer cases and 19,715 controls from the PRACTICAL consortium and 5,504 prostate cancer cases and 5,834 controls from the CRUK prostate cancer study. Results:Calculating the average additive effect of type 2 diabetes or glycemic trait risk alleles on prostate cancer risk using a logistic model revealed no evidence of a shared allelic architecture between type 2 diabetes, or worsened glycemic status, with prostate cancer risk (odds ratio for type 2 diabetes alleles: 1.00 (P=0.58), fasting glycemia alleles: 1.00 (P=0.67), HbA1c alleles: 1.00 (P=0.93), 2 hour OGTT alleles: 1.01 (P=0.14) and HOMA-B alleles: 0.99 (P=0.57)). Conclusions:Using genetic data from large consortia we found no evidence for a shared genetic etiology of type 2 diabetes, or glycemic risk, with prostate cancer. Impact:Our results showed that alleles influencing type 2 diabetes and related glycemic traits were not found to be associated with the risk of prostate cancer.
Cancer Epidemiology Biomarkers & Prevention 05/2013; · 4.56 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: PURPOSETo analyze the baseline clinicopathologic characteristics of prostate tumors with germline BRCA1 and BRCA2 (BRCA1/2) mutations and the prognostic value of those mutations on prostate cancer (PCa) outcomes. PATIENTS AND METHODS
This study analyzed the tumor features and outcomes of 2,019 patients with PCa (18 BRCA1 carriers, 61 BRCA2 carriers, and 1,940 noncarriers). The Kaplan-Meier method and Cox regression analysis were used to evaluate the associations between BRCA1/2 status and other PCa prognostic factors with overall survival (OS), cause-specific OS (CSS), CSS in localized PCa (CSS_M0), metastasis-free survival (MFS), and CSS from metastasis (CSS_M1).ResultsPCa with germline BRCA1/2 mutations were more frequently associated with Gleason ≥ 8 (P = .00003), T3/T4 stage (P = .003), nodal involvement (P = .00005), and metastases at diagnosis (P = .005) than PCa in noncarriers. CSS was significantly longer in noncarriers than in carriers (15.7 v 8.6 years, multivariable analyses [MVA] P = .015; hazard ratio [HR] = 1.8). For localized PCa, 5-year CSS and MFS were significantly higher in noncarriers (96% v 82%; MVA P = .01; HR = 2.6%; and 93% v 77%; MVA P = .009; HR = 2.7, respectively). Subgroup analyses confirmed the poor outcomes in BRCA2 patients, whereas the role of BRCA1 was not well defined due to the limited size and follow-up in this subgroup. CONCLUSION
Our results confirm that BRCA1/2 mutations confer a more aggressive PCa phenotype with a higher probability of nodal involvement and distant metastasis. BRCA mutations are associated with poor survival outcomes and this should be considered for tailoring clinical management of these patients.
Journal of Clinical Oncology 04/2013; · 18.04 Impact Factor
[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 = 2.7x10(-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 = 1.4x10(-8), HR = 1.27, 95% CI: 1.17-1.38) and 4q32.3 (rs4691139, P = 3.4x10(-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 = 2x10(-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.
[Show abstract][Hide abstract] ABSTRACT: Prostate cancer (CaP) is the leading cancer among men of African descent in the USA, Caribbean, and Sub-Saharan Africa (SSA). The estimated number of CaP deaths in SSA during 2008 was more than five times that among African Americans and is expected to double in Africa by 2030. We summarize publicly available CaP data and collected data from the men of African descent and Carcinoma of the Prostate (MADCaP) Consortium and the African Caribbean Cancer Consortium (AC3) to evaluate CaP incidence and mortality in men of African descent worldwide. CaP incidence and mortality are highest in men of African descent in the USA and the Caribbean. Tumor stage and grade were highest in SSA. We report a higher proportion of T1 stage prostate tumors in countries with greater percent gross domestic product spent on health care and physicians per 100,000 persons. We also observed that regions with a higher proportion of advanced tumors reported lower mortality rates. This finding suggests that CaP is underdiagnosed and/or underreported in SSA men. Nonetheless, CaP incidence and mortality represent a significant public health problem in men of African descent around the world.
[Show abstract][Hide abstract] ABSTRACT: Genome-wide association studies (GWAS) have identified multiple common genetic variants associated with an increased risk of prostate cancer (PrCa), but these explain less than one third of the heritability. To identify further susceptibility alleles, we conducted a meta-analysis of four genome-wide association studies (GWAS) including 5,953 cases of aggressive PrCa and 11,463 controls (men without PrCa). We computed association tests for ~2.6M SNPs and followed up the most significant SNPs by genotyping 49,121 samples in 29 studies through the international PRACTICAL and BPC3 consortia. We not only confirmed the association of a PrCa susceptibility locus, rs11672691 on chromosome 19, but also showed an association with aggressive PrCa (OR=1.12 (95% CI 1.03-1.21), P=1.4x10(-8)). This report describes a genetic variant which is associated with aggressive prostate cancer, which is a type of prostate cancer associated with a poorer prognosis.
Human Molecular Genetics 10/2012; · 7.69 Impact Factor