68 research outputs found
Dominantânegative pathogenic variant BRIP1 c. 1045G >C is a highârisk allele for nonâmucinous epithelial ovarian cancer: A caseâcontrol study
From Wiley via Jisc Publications RouterHistory: received 2021-08-12, rev-recd 2021-09-16, accepted 2021-09-27, pub-electronic 2021-10-07Article version: VoRPublication status: PublishedFunder: Cancer Research UK Manchester Centre; Id: http://dx.doi.org/10.13039/501100017008; Grant(s): C147/A18083, C147/A25254Funder: National Institute for Health Research; Id: http://dx.doi.org/10.13039/501100000272; Grant(s): NIHR300650Funder: National Institute for Health Research (NIHR) Manchester Biomedical Research Centre; Grant(s): ISâBRCâ1215â20007Funder: Prevent Breast Cancer; Grant(s): GA 15â002, GA19â002Abstract: BRIP1 is a moderate susceptibility epithelial ovarian cancer (EOC) gene. Having identified the BRIP1 c.1045G>C missense variant in a number of families with EOC, we aimed to investigate the frequency of this and BRIP1.2392C>T pathogenic variant in patients with breast cancer (BC) and/or EOC. A caseâcontrol study of 3767 cases and 2043 controls was undertaken investigating the presence of these variants using Sanger sequencing and gene panel data. Individuals with BC and/or EOC were grouped by family history. BRIP1 c.1045G>C was associated with increased risk of BC/EOC (OR = 37.7; 95% CI 5.3â444.2; P = 0.0001). The risk was highest for women with EOC (OR = 140.8; 95% CI 23.5â1723.0; P T was associated with smaller risks for BC/EOC (OR = 5.4; 95%CI 2.4â12.7; P = 0.0003), EOC (OR = 5.9; 95% CI 1.3â23.0; p = 0.0550) and BC (OR = 5.3; 95%CI 2.3â12.9; P = 0.0009). Our study highlights the importance of BRIP1 as an EOC susceptibility gene, especially in familial EOC. The variant BRIP1 c.1045G>C, rs149364097, is of particular interest as its dominantânegative effect may confer a higher risk of EOC than that of the previously reported BRIP1 c.2392C>T nonsense variant. Dominantânegative missense variants may confer higher risks than their lossâofâfunction counterparts
Differential involvement of germline pathogenic variants in breast cancer genes between DCIS and low-grade invasive cancers
Gene Panel Testing for Breast Cancer Reveals Differential Effect of Prior BRCA1/2 Probability
From MDPI via Jisc Publications RouterHistory: accepted 2021-08-16, pub-electronic 2021-08-18Publication status: PublishedFunder: Manchester Biomedical Research Centre; Grant(s): IS-BRC-1215-20007Funder: Prevent breast cancer; Grant(s): GA19-002Whilst panel testing of an extended group of genes including BRCA1/2 is commonplace, these studies have not been subdivided by histiotype or by a priori BRCA1/2 probability. Patients with a breast cancer diagnosis undergoing extended panel testing were assessed for frequency of actionable variants in breast cancer genes other than BRCA1/2 by histiotype and Manchester score (MS) to reflect a priori BRCA1/2 likelihood. Rates were adjusted by prior testing for BRCA1/2 in an extended series. 95/1398 (6.3%) who underwent panel testing were found to be positive for actionable non-BRCA1/2 breast/ovarian cancer genes (ATM, BARD1, CDH1, CHEK2, PALB2, PTEN, RAD51C, RAD51D, TP53). As expected, PALB2, CHEK2 and ATM were predominant with 80-(5.3%). The highest rate occurred in Grade-3 ER+/HER2â breast cancers-(9.6%). Rates of non-BRCA actionable genes was fairly constant over all likelihoods of BRCA1/2 but adjusted rates were three times higher with MS 9 (BRCA1/2 = 1.5%, other = 4.7%), but was only 1.6% compared to 79.3% with MS â„ 40. Although rates of detection of non-BRCA actionable genes are relatively constant across BRCA1/2 likelihoods this disguises an overall adjusted low frequency in high-likelihood families which have been heavily pre-tested for BRCA1/2. Any loss of detection sensitivity for BRCA1/2 actionable variants in breast cancer panels should lead to bespoke BRCA1/2 testing being conducted first
A Dominantly Inherited 5' UTR Variant Causing Methylation-Associated Silencing of BRCA1 as a Cause of Breast and Ovarian Cancer
Pathogenic variants in BRCA1 or BRCA2 are identified in âŒ20% of families with multiple individuals affected by early-onset breast and/or ovarian cancer. Extensive searches for additional highly penetrant genes or alternative mutational mechanisms altering BRCA1 or BRCA2 have not explained the missing heritability. Here, we report a dominantly inherited 5âČ UTR variant associated with epigenetic BRCA1 silencing due to promoter hypermethylation in two families affected by breast and ovarian cancer. BRCA1 promoter methylation of ten CpG dinucleotides in families who are affected by breast and/or ovarian cancer but do not have germline BRCA1 or BRCA2 pathogenic variants was assessed by pyrosequencing and clonal bisulfite sequencing. RNA and DNA sequencing of BRCA1 from lymphocytes was undertaken to establish allelic expression and the presence of germline variants. BRCA1 promoter hypermethylation was identified in 2 of 49 families in which multiple women are affected by grade 3 breast cancer or high-grade serous ovarian cancer. Soma-wide BRCA1 promoter hypermethylation was confirmed in blood, buccal mucosa, and hair follicles. Pyrosequencing showed that DNA was âŒ50% methylated, consistent with the silencing of one allele, which was confirmed by clonal bisulfite sequencing. RNA sequencing revealed the allelic loss of BRCA1 expression in both families and that this loss of expression segregated with the heterozygous variant c.â107A>T in the BRCA1 5âČ UTR. Our results establish a mechanism whereby familial breast and ovarian cancer is caused by an in cis 5âČ UTR variant associated with epigenetic silencing of the BRCA1 promoter in two independent families. We propose that methylation analyses be undertaken to establish the frequency of this mechanism in families affected by early-onset breast and/or ovarian cancer without a BRCA1 or BRCA2 pathogenic variant
Transmission of molecularly undetectable circulating parasite clones leads to high infection complexity in mosquitoes post feeding.
Plasmodium falciparum malaria infections often comprise multiple distinct parasite clones. Few datasets have directly assessed infection complexity in humans and mosquitoes they infect. Examining parasites using molecular tools may provide insights into the selective transmissibility of isolates. Using capillary electrophoresis genotyping and next generation amplicon sequencing, we analysed complexity of parasite infections in human blood and in the midguts of mosquitoes that became infected in membrane feeding experiments using the same blood material in two West African settings. Median numbers of clones in humans and mosquitoes were higher in samples from Burkina Faso (4.5, interquartile range 2-8 for humans; and 2, interquartile range 1-3 for mosquitoes) than in The Gambia (2, interquartile range 1-3 and 1, interquartile range 1-3, for humans and mosquitoes, respectively). Whilst the median number of clones was commonly higher in human blood samples, not all transmitted alleles were detectable in the human peripheral blood. In both study sample sets, additional parasite alleles were identified in mosquitoes compared with the matched human samples (10-88.9% of all clones/feeding assay, nâŻ=âŻ73 feeding assays). The results are likely due to preferential amplification of the most abundant clones in peripheral blood but confirm the presence of low density clones that produce transmissible sexual stage parasites
Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis
BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
ARTICLEAssociation of the CHEK2 c.1100delC variant, radiotherapy, and systemic treatment with contralateral breast cancer risk and breast cancer-specific survival
Aim
To assessed the associations of CHEK2 c.1100delC, radiotherapy, and systemic treatment with CBC risk and BCSS.
Methods
Analyses were based on 82,701 women diagnosed with a first primary invasive BC including 963 CHEK2 c.1100delC carriers; median follow-up was 9.1âyears. Differential associations with treatment by CHEK2 c.1100delC status were tested by including interaction terms in a multivariable Cox regression model. A multi-state model was used for further insight into the relation between CHEK2 c.1100delC status, treatment, CBC risk and death.
Results
There was no evidence for differential associations of therapy with CBC risk by CHEK2 c.1100delC status. The strongest association with reduced CBC risk was observed for the combination of chemotherapy and endocrine therapy [HR (95% CI): 0.66 (0.55â0.78)]. No association was observed with radiotherapy. Results from the multi-state model showed shorter BCSS for CHEK2 c.1100delC carriers versus non-carriers also after accounting for CBC occurrence [HR (95% CI): 1.30 (1.09â1.56)].
Conclusion
Systemic therapy was associated with reduced CBC risk irrespective of CHEK2 c.1100delC status. Moreover, CHEK2 c.1100delC carriers had shorter BCSS, which appears not to be fully explained by their CBC risk
Spectrum and Frequency of Germline FANCM Protein-Truncating Variants in 44,803 European Female Breast Cancer Cases
Combined Associations of a Polygenic Risk Score and Classical Risk Factors With Breast Cancer Risk.
We evaluated the joint associations between a new 313-variant PRS (PRS313) and questionnaire-based breast cancer risk factors for women of European ancestry, using 72 284 cases and 80 354 controls from the Breast Cancer Association Consortium. Interactions were evaluated using standard logistic regression and a newly developed case-only method for breast cancer risk overall and by estrogen receptor status. After accounting for multiple testing, we did not find evidence that per-standard deviation PRS313 odds ratio differed across strata defined by individual risk factors. Goodness-of-fit tests did not reject the assumption of a multiplicative model between PRS313 and each risk factor. Variation in projected absolute lifetime risk of breast cancer associated with classical risk factors was greater for women with higher genetic risk (PRS313 and family history) and, on average, 17.5% higher in the highest vs lowest deciles of genetic risk. These findings have implications for risk prevention for women at increased risk of breast cancer
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