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This article presents proteomics data referenced in [1] Using proteomics-based evaluation of red blood cells (RBCs), we have identified differentially abundant proteins associated with Obstructive Sleep Apnea Syndrome (OSA). RBCs were collected from peripheral blood of patients with moderate/severe OSA or snoring at pre- (evening) and post-night (morning) polysomnography, so that proteome variations between these time points could be assessed. RBC cytoplasmic fraction depleted of hemoglobin, using Hemovoid™ system, were analyzed by two-dimensional fluorescence difference gel electrophoresis (2D-DIGE), the 2D image software-based analyzed and relevant differentially abundant proteins identified by mass spectrometry (MS). MS identified 31 protein spots differentially abundant corresponding to 21 unique proteins possibly due to the existence of post-translational modification regulations. Functional analysis by bioinformatics tools indicated that most proteins are associated with catalytic, oxidoreductase, peroxidase, hydrolase, ATPase and anti-oxidant activity. At morning a larger numbers of differential proteins including response to chemical stimulus, oxidation reduction, regulation of catalytic activity and response to stress were observed in OSA. The data might support further research in OSA biomarker discovery and validation.

We have examined the effects of Obstructive Sleep Apnea (OSA) on red blood cell (RBC) proteome variation at evening/morning day time to uncover new insights into OSA-induced RBC dysfunction that may lead to OSA manifestations. Dysregulated proteins mainly fall in the group of catalytic enzymes, stress response and redox regulators such as peroxiredoxin 2 (PRDX2). Validation assays confirmed that at morning the monomeric/dimeric forms of PRDX2 were more overoxidized in OSA RBC compared to evening samples. Six month of positive airway pressure (PAP) treatment decreased this overoxidation and generated multimeric overoxidized forms associated with chaperone/transduction signaling activity of PRDX2. Morning levels of overoxidized PRDX2 correlated with polysomnographic (PSG)-arousal index and metabolic parameters whereas the evening level of disulfide-linked dimer (associated with peroxidase activity of PRDX2) correlated with PSG parameters. After treatment, morning overoxidized multimer of PRDX2 negatively correlated with fasting glucose and dopamine levels. Overall, these data point toward severe oxidative stress and altered antioxidant homeostasis in OSA RBC occurring mainly at morning time but with consequences till evening. The beneficial effect of PAP involves modulation of the redox/oligomeric state of PRDX2, whose mechanism and associated chaperone/transduction signaling functions deserves further investigation. RBC PRDX2 is a promising candidate biomarker for OSA severity and treatment monitoring, warranting further investigation and validation.

Obstructive sleep apnea (OSA) is an underdiagnosed common public health concern causing deleterious effects on metabolic and cardiovascular health. Although much has been learned regarding the pathophysiology and consequences of OSA in the past decades, the molecular mechanisms associated with such processes remain poorly defined. The advanced high-throughput proteomics-based technologies have become a fundamental approach for identifying novel disease mediators as potential diagnostic and therapeutic targets for many diseases, including OSA. Here, we briefly review OSA pathophysiology and the technological advances in proteomics and the first results of its application to address critical issues in the OSA field.

Simple Summary: Approximately 10% of breast cancer (BC) cases are hereditary, and germline pathogenic variants in BRCA1 and BRCA2 genes account for 20% of familial BC cases. Long-term follow-up data related to the prognosis and survival of either BRCA1 or BRCA2 BC patients are conflicting. The aim of this study is to report the analysis of our cohort of BRCA1/2 BC patients included in prospective follow-up after genetic testing. We compared clinicopathological characteristics and prognosis between BC patients with BRCA1 and BRCA2 and a control group without germline PV (BRCA-wt). The presence of BRCA mutation confers a higher risk of relapse and death in patients with BC in the Portuguese population. Prophylactic mastectomy and preventive salpingo-oophorectomy confer lower incidence of relapse and longer median invasive disease-free survival and overall survival, respectively. Background: Germline pathogenic variants (PV) in BRCA1 and BRCA2 genes, which account for 20% of familial breast cancer (BC) cases, are highly penetrant and are associated with Hereditary Breast/Ovarian Cancer Syndrome. Previous studies, mostly including higher numbers of BRCA1 BC patients, yielded conflicting results regarding BRCA1/2 BC outcomes. In the Portuguese population, BRCA2 BC is diagnosed more frequently than BRCA1 BC. We aimed to compare clinicopathological characteristics and prognosis between BC patients with BRCA1 and BRCA2 mutations and a control group without germline PV (BRCA-wt). Furthermore, we explored the frequency and outcomes of risk-reducing surgeries in BRCA-mutated patients. Methods: Prospective follow-up was proposed for patients with a diagnosed BRCA1/2 PV. For this study, a matched control group (by age at diagnosis, by decade, and by stage at diagnosis) included BC patients without germline PV. We compared overall survival (OS) and invasive disease-free survival (iDFS) within the three groups, and the use of risk-reducing surgeries among the BRCA cohort. Results: For a mean follow-up time of 113.0 months, BRCA-wt patients showed longer time to recurrence (p = 0.002) and longer OS (p < 0.001). Among patients with BRCA mutations, no statistical differences were found, although patients with BRCA2 BC had longer iDFS and OS. Uptake of risk-reducing surgeries (contralateral prophylactic mastectomy and salpingo-oophorectomy) were negative predictors of invasive disease and death, respectively. Conclusions: Testing positive for a BRCA PV is associated with a higher risk of relapse and death in patients with BC in the Portuguese population. Risk-reducing mastectomy and salpingo-oophorectomy were associated with lower incidence of relapse and longer median iDFS and OS, respectively. [ABSTRACT FROM AUTHOR]

Background: Risk-reducing surgeries are an option for cancer risk management in BRCA1/2 individuals. However, while adnexectomy is commonly recommended in breast cancer (BC) survivors, risk-reducing bilateral breast surgery (RRBBS) is controversial in ovarian cancer (OC) survivors due to relapse rates and mortality. Methods: We conducted a retrospective analysis of BRCA1/2-OC survivors, with OC as first cancer diagnosis. Results: Median age at OC diagnosis for the 69 BRCA1/2-OC survivors was 54 years. Median overall survival was 8 years, being significantly higher for BRCA2 patients than for BRCA1 patients (p = 0.011). Nine patients (13.2%) developed BC at a median age of 61 years. The mean overall BC-free survival was 15.5 years (median not reached). Eight patients (11.8%) underwent bilateral mastectomy (5 simultaneous with BC treatment; 3 RRBBS) at a median age of 56.5 years. The median time from OC to bilateral mastectomy/RRBBS was 5.5 years. Conclusions: This study adds evidence regarding a lower BC risk after BRCA1/2-OC and higher survival for BRCA2-OC patients. A comprehensive analysis of the competing risks of OC mortality and recurrence against the risk of BC should be individually addressed. Surgical BC risk management may be considered for longer BRCA1/2-OC disease-free survivors. Ultimately, these decisions should always be tailored to patients' characteristics and preferences. [ABSTRACT FROM AUTHOR]

Cancer survivors harboring inherited pathogenic variants in the breast cancer (BC) susceptibility genes BRCA1 or BRCA2 are at increased risk of ovarian cancer (OC) and also of contralateral BC. For these women, risk-reducing surgery (RRS) may contribute to risk management. However, women with locally advanced or metastatic breast cancer (ABC) were excluded from clinical trials evaluating the benefit of these procedures in the BRCA1/2 carriers, and thus, current guidelines do not recommend RRS in this specific setting. Although ABC remains an incurable disease, recent advances in treatment have led to increased survival, which, together with improvement in RRS techniques, raise questions about the potential role of RRS in the management of BRCA1/2 ABC patients. When should RRS be discussed as an option for BRCA1/2 patients diagnosed with ABC? To address this issue, we report two clinical cases that reflect new challenges in routine oncology practice. Team experience and patient motivations may shape multidisciplinary decisions in the absence of evidence-based data. A wise rationale may be the analysis of the competing risks of death by a previous ABC against risk of death by a secondary BC or OC, tailored to patient preferences. [ABSTRACT FROM AUTHOR]

Male breast cancer (BC) represents an individual subtype of BC, with therapeutic procedures based on female BC therapy results. The present study evaluated the parameters currently used for the characterization and therapy of male BC, and their association with disease-free (DFS) and overall survival (OS), aiming to obtain a comprehensive basis to improve the personalized care of male BC. A total of 196 patients from March 1970 to March 2018 (mean follow-up, 84.9 months) were profiled, using clinicopathological review, molecular assessment [BRCA1/2, DNA repair associated (BRCA1/2) status, immunohistochemistry, fluorescence in situ hybridization and DNA flow cytometry] and Cox regression statistical analysis. The median age of patients was 66.5 years. At presentation, 39.2% of patients with invasive carcinomas were in anatomic stage (AS) I. Patients exhibited primarily invasive carcinomas of no special type, histological grade 2, estrogen receptor α-(ERα) and progesterone receptor (PR)-positive, receptor tyrosine kinase erbB-2-negative, high Ki-67, Luminal B-like and aneuploid tumors. A total of 13 of the 44 (29.5%) BRCA-evaluated patients exhibited BRCA2 mutations, significantly associated with family history (FH), bilaterality, high Ki-67 expression, absence of PR and Luminal B-like tumors. Bilaterality was associated with the occurrence of non-breast primary neoplasms (NBPN). The 5 and 10-year DFS rates, excluding patients with distant metastasis, NBPN and in situ carcinomas (n=145) were 65.9 and 58.2%, respectively, and the 5 and 10-year OS rates were 77.5 and 59.2%, respectively. In the univariate analysis, Luminal B-like subtype, BRCA2 mutations, high Ki-67 expression, and AS II and III were significantly associated with shorter DFS and OS. In addition, age >70 years was associated with low OS. In the multivariate analysis, FH, AS II and III, and Luminal B-like subtypes were associated with poorer OS. In conclusion, the data from the present study emphasize the high incidence of BRCA2 mutation in male BC, and its association with FH, bilaterality, high Ki-67 expression, negative PR expression and Luminal B-like subtypes, and with shorter DFS and OS in univariate analysis. [ABSTRACT FROM AUTHOR]

Introduction. Sentinel lymph node biopsy in prophylactic mastectomy is controversial. It avoids lymphadenectomy in occult carcinoma but is associated with increased morbidity. Women with BRCA mutations have a higher incidence of occult carcinoma and our objective was to assess the clinical utility of sentinel lymph node biopsy when these women undergo prophylactic mastectomy. Materials and Methods. Seven-year retrospective consecutive case-series study of women, with a BRCA deleterious mutation, admitted to prophylactic mastectomy, at our center. Breast MRI < 6 months before surgery was routine, unless contraindicated. Results. Fifty-seven patients (43% BRCA1; 57% BRCA2) underwent 80 prophylactic mastectomies. 72% of patients had had breast cancer treated before prophylactic mastectomy or synchronously to it. The occult carcinoma incidence was 5%, and half of the cases were invasive. SLNB was performed in 19% of the prophylactic mastectomies; none of these had tumor invasion. Women with invasive carcinoma who had not undergone sentinel lymph node biopsy were followed closely with axillary ultrasound. The median follow-up was 37 months, with no local recurrence; 1 patient died of primary tumor systemic relapse. Conclusions. Our data do not support this procedure for routine (in agreement with previous literature), in this high risk for occult carcinoma population. [ABSTRACT FROM AUTHOR]

Leptomeningeal carcinomatosis is a rare metastatic event in gynecological neoplasias, and most cases occur in ovarian cancer. It is extremely infrequent in cervical cancer, and so far, there are not any reports of this complication in association with endometrial cancer.We report a case of leptomeningeal carcinomatosis secondary to endometrial carcinoma and 2 complex cervix cancer cases. A MEDLINE search was done to review all published cases of this complication in gynecological cancer to identify predictive factors for this diagnosis.Leptomeningeal carcinomatosis is usually diagnosed late in the course of the disease, and most reports concern ovarian cancer patients. The number of cases describing this neurologic complication in cervix cancer is increasing. Gadolinium-enhanced magnetic resonance imaging may be necessary for this diagnosis, because cerebrospinal fluid analysis results may be negative. Most cervix cases had squamous cell (8/14) or neuroendocrine histologic subtype (3/14), and when reported, differentiation was usually poor. The case we report of endometrial carcinoma, unique in the literature, is a serous adenocarcinoma.A high index of suspicion is necessary, and leptomeningeal carcinomatosis should be considered in patients with unexplained neurologic symptoms whose gynecologic tumors are poorly undifferentiated or have a serous component. [ABSTRACT FROM AUTHOR]

Examines the minimal perimeter enclosing a cluster of N planar bubbles of identical areas in two dimensions. Topological classification of defect-free configurations; Clusters extracted from a honeycomb lattice; Conditions required for minimal configuration.

In this study, we examined the effect of six months of positive airway pressure (PAP) therapy on Obstructive Sleep Apnea (OSA) red blood cell (RBC) proteome by two dimensional difference gel electrophoresis (2D-DIGE) - based proteomics followed by Western blotting (WB) validation. The discovered dysregulated proteins/proteoforms are associated with cell death, H2O2 catabolic/metabolic process, stress response, and protein oligomerization. Validation by nonreducing WB was performed for peroxiredoxin-2 (PRDX2) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) by using antibodies against the sulfinylated/sulfonylated cysteine of these proteins to better evaluate their redox–oligomeric states under OSA and/or in response to PAP therapy. The results indicated that the redox–oligomeric state of GAPDH and PRDX2 involving overoxidation by sulfinic/sulfonic acids were differentially modulated in OSA RBC, which might be compromising RBC homeostasis. PAP therapy by restoring this modulation induced a higher oligomerization of overoxidized GAPDH and PRDX2 in some patients that could be associated with eryptosis and the chaperone "gain" of function, respectively. This varied response following PAP may result from the complex interplay between OSA and OSA metabolic comorbidity. Hence, information on the redox status of PRDX2 and GAPDH in RBC will help to better recognize OSA subtypes and predict the therapeutic response in these patients. GAPDH monomer combined with body mass index (BMI) and PRDX2 S-S dimer combined with homeostatic model assessment for insulin resistance (HOMA-IR) showed to be very promising biomarkers to predict OSA and OSA severity, respectively. [ABSTRACT FROM AUTHOR]

Nasopharyngeal carcinomas (NPC) are endemic in southeast Asia and rare in Europe with an incidence of 0.07/100.000 persons. Five-year survival is about 50%. Diagnosis is provided by histological findings and staging classification is done according to AJCC. EBV DNA serum levels should be determined before and after local treatment, carry prognostic significance and can be used in the active surveillance of cancer survivors. The best method for serum determination of EBV DNA is still under discussion. Advanced locoregional disease carries a greater risk of distant spread, highlighting the need of treatment intensification in higher risk patients. The best treatment plan is still under discussion: concurrent chemoradiation followed by adjuvant chemotherapy (ACT) or induction chemotherapy (ICT) followed by chemoradiation. ACT/ICT regimens should consist of two-/three-drug regimens, including a platinum agent and the best drug regimen is still under investigation. ACT carries great toxicity (50% require dose reductions, 60% complete treatment) and has a relatively low PFS and OS benefit. ICT is better tolerated, but may compromise cisplatin cumulative dose in concomitant chemoradiation and delay radiation start, possibly compromising the effectiveness of local treatment. Nonetheless, ICT improves PFS and OS when compared to chemoradiation alone, mostly because of better metastasis free survival (MFS), making this a promising strategy in properly selected high risk patients. Most NPC trials were conducted in countries where NPC is endemic, primarily non-queratinizing and EBV-related. Data in non-endemic countries are lacking. Our study aims to compare ACT and ICT in locally advanced and oligometastatic NPC patients treated in a European reference centre. Retrospective, observational study of patients with NPC diagnosis between January 2017 and September 2023 and disease stage III-IVb. Data were collected from patient records and included patient characteristics (gender, age, smoking history, ECOG performance status), tumor characteristics (T, N, staging, histology, EBV-status) and treatment characteristics (ACT, ICT, toxicities). PFS and OS were analyzed. Toxicity grading is according to CTCAE 5.0 and statistical analysis is descriptive. A total of 69 patients were included. Most patients were male (56.5%, n=39) with a median age of 53.0 years (18-75). Most patients had a good performance status (0 or 1 in 98.5%, n=68). Stage IVa was the most frequent initial staging (50.7%, n=35), with a majority of patients having T4 (33.3%, n=23) and N3 (39.1%, n=27) tumours. All tumours were undifferentiated queratinizing carcinomas and 86.9% (n=60) were EBV-positive. EBV DNA was rarely determined. [Display omitted] Until 2019 the most frequent treatment strategy was ACT with cisplatin-5FU (57.9%, n=40), after which ICT became more frequently used (15.9%, n=11), mostly with cisplatin-gemcitabin (45.4%, n=5). ICT had less acute toxicities that lead to treatment discontinuation (0.9% (n=1) versus 39.7% (n=23)). All patients completed radiotherapy after ICT, but in 4 patients optimal concomitant cisplatin dose (≥200mg/m2) was compromised. Both ICT and ACT showed good response rates, with a complete response in 63.6% versus 79.3%, respectively. Median follow up was 45 months in the ACT group (4-125) and 27 months (1-55) in the ICT group. PFS with ACT was 45.0 months (95%CI 34.8-55.2) and OS was 46.0 months (95%CI 38.5-53.4). The ICT group is small and has a short follow-up time; PFS and OS data will be determined in the future. [Display omitted] The best course of treatment of advanced NPC is still unclear - which patients and histologies benefit most from treatment intensification? What is the role of EBV DNA and what is the best method for its determination? Should ACT or ICT be preferred? Which chemotherapy regimen is better? Treatment center expertise and the ability to provide timely treatment may also play a role in treatment decisions. Our study presents the experience of a European reference centre where ACT was the preferred treatment for a longer period of time and therefore has a significantly larger patient population with longer follow-up time. ACT seems to provide good patient outcomes, despite a worse toxicity profile and more related treatment discontinuations, but group comparison is not yet possible since our centre only recently changed strategies in managing advanced NPC patients, preferring ICT over ACT. ICT patients are still underrepresented in this analysis, with fewer patients and shorter follow-up time. Moreover, the ICT patient group has more advanced disease, including IVb oligometastatic disease (that was not included in the intensification ACT and ICT studies), making head-to-head comparisons difficult. The management of advanced NPC is a clinical challenge and more data are needed to better select both patients and treatment strategies for treatment intensification, while taking into consideration the differences between endemic and non-endemic NPC. [ABSTRACT FROM AUTHOR]

Background: Hereditary breast and ovary cancer syndrome affects both genders but little is known about the uptake of genetic services by men. The objective of this study is to characterise the male population counselled through a multidisciplinary breast/ovarian program. Methods: Descriptive analysis of male patients counselled from January 2000 to December 2015. Data in this analysis include new cancer diagnoses during prospective follow up. Results: From 4,320 families registered, 362 male patients were identified: 236 (65.2%) from hereditary cancer families (HCF) and 126 (34.8%) from non-HCF. In HCF, 121 patients (51.3%) were mutation carriers (MC): BRCA2 - 102 (84.3%), BRCA1 - 16 (13.2%), CHEK2 - 1 (0.8%) and TP53 - 2 (1.7%). Non-HCF included 126 patients: 85 (67.5%) belonged to families without pathogenic mutations or with variants of unknown clinical significance; 22 (17.5%) refused testing after counselling and 19 (15.0%) did not meet criteria for testing. Both HCF and non-HCF included patients with previous cancer diagnoses: HCF- Breast Cancer (BC) - 18; prostate cancer (PC) - 13; melanoma - 1; others - 7) and non-HCF (BC - 77; PC - 20; gastric cancer (GC) - 1; melanoma - 8; bladder cancer - 1; others - 22). From the 121 MC identified (including the TP53 and CHEK2 carriers), 97 patients (80.2%) adhered to prospective surveillance. With a median follow-up of 36.9 months, 17 cancers were diagnosed in 14 patients, PC being the most frequently diagnosed neoplasia (5 cases). Eleven patients (78.6%) are alive and three patients died of advanced cancer (2 with GC, 1 with disseminated adenocarcinoma). Conclusion: We observed a high adherence to counselling, genetic testing and active surveillance by men belonging to hereditary BC families. Male carriers of pathogenic DNA variants are at risk for several cancers and should be included in prospective follow-up studies. [ABSTRACT FROM AUTHOR]

Abstract: The organization of respiratory chain complexes in supercomplexes has been shown in the mitochondria of several eukaryotes and in the cell membranes of some bacteria. These supercomplexes are suggested to be important for oxidative phosphorylation efficiency and to prevent the formation of reactive oxygen species. Here we describe, for the first time, the identification of supramolecular organizations in the aerobic respiratory chain of Escherichia coli, including a trimer of succinate dehydrogenase. Furthermore, two heterooligomerizations have been shown: one resulting from the association of the NADH:quinone oxidoreductases NDH-1 and NDH-2, and another composed by the cytochrome bo 3 quinol:oxygen reductase, cytochrome bd quinol:oxygen reductase and formate dehydrogenase (fdo). These results are supported by blue native-electrophoresis, mass spectrometry and kinetic data of wild type and mutant E . coli strains. [Copyright &y& Elsevier]

Access to genetic testing and counselling in remote areas such as the Madeira archipelago, in the Northern Atlantic Ocean, may be complex. Different counselling methods, including telegenetics, should be explored. In this study, we characterise the Hereditary Breast/Ovarian Cancer (HBOC) families with Madeira ancestry enrolled in our programme. Of a total of 3,566 index patients tested between January 2000 and June 2018, 68 had Madeira ancestry and 22 were diagnosed with a pathogenic germline variant (PV). As in the whole group, BRCA2 PV were more frequent in Madeira patients (68.4%: c.9382C>T (26.3%), c.658&#95;659del (21%), c.156&#95;157insAlu (10.5%), c.793+1G>A (5.3%) and c.298A>T (5.3%). However, the most frequently diagnosed PV in Madeira patients was the BRCA1 c.3331&#95;3334del (31.6%). BRCA1/2 detection rates were 27.9% and 10.5% for Madeira and the whole group, respectively. This study is the first characterisation of HBOC patients with Madeira ancestry. A distinct pattern of BRCA1/2 variants was observed, and the geographic clustering of BRCA1 c.3331&#95;3334del variant may support the possibility of a founder mutation previously described in Northern Portugal. The high detection rate observed reinforces the need to reduce gaps in access to genetic testing in Madeira and other remote areas. According to current guidelines, timely identification of HBOC patients can contribute to their ongoing care and treatment., Competing Interests: The authors declare that they have no conflict of interest., (© the authors; licensee ecancermedicalscience.)

Environmental tobacco smoke (ETS) has been recognized as a major health hazard by environmental and public health authorities worldwide. In Portugal, smoke-free laws are in force for some years, banning smoking in most indoor public spaces. However, in hospitality venues such as restaurants and bars, owners can still choose between a total smoke-free policy or a partial smoking restriction with designated smoking areas, if adequate reinforced ventilation systems are implemented. Despite that, a previous study showed that workers remained continuously exposed to higher ETS pollution in Lisbon restaurants and bars where smoking was still allowed, comparatively to total smoke-free venues. This was assessed by measurements of indoor PM 2.5 and urinary cotinine, a biomarkers of tobacco smoke exposure, demonstrating that partial smoking restrictions do not effectively protect workers from ETS. The aim of the present work was to characterize effect and susceptibility biomarkers in non-smokers from those hospitality venues occupationally exposed to ETS comparatively to non-exposed ones. A group of smokers was also included for comparison. The sister chromatid exchange (SCE), micronucleus (MN) and comet assays in whole peripheral blood lymphocytes (PBLs) and the micronucleus assay in exfoliated buccal cells, were used as biomarkers of genotoxicity. Furthermore, a comet assay after ex vivo challenge of leukocytes with an alkylating agent, ethyl methanesulfonate (EMS), was used to analyze the repair capacity of those cells. Genetic polymorphisms in genes associated with metabolism and DNA repair were also included. The results showed no clear association between occupational exposure to ETS and the induction of genotoxicity. Interestingly, the leukocytes from non-smoking ETS-exposed individuals displayed lower DNA damage levels in response to the ex vivo EMS challenge, in comparison to those from non-exposed workers, suggesting a possible adaptive response. The contribution of individual susceptibility to the effect biomarkers studied was unclear, deserving further investigation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Vital, Antunes, Louro, Vaz, Simões, Penque and Silva.)

Male breast cancer is rare and has been frequently associated with cancer predisposing variants, particularly in BRCA 1 and BRCA 2 genes. ATM pathogenic variants may also increase risk for breast and other cancers. However, less than 10 cases relating ATM mutations and male breast cancer have been previously reported. Therefore, risk estimates and surveillance recommendations are not well established. We report a case of a male patient with breast cancer found to be heterozygous for a pathogenic ATM variant after multigene testing. We also review the literature regarding increased cancer risk associated with ATM germline variants, with emphasis on potential recommendations for surveillance and follow-up., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

BRCA2 is a clinically actionable gene implicated in breast and ovarian cancer predisposition that has become a high priority target for improving the classification of variants of unknown significance (VUS). Among all BRCA2 VUS, those causing partial/leaky splicing defects are the most challenging to classify because the minimal level of full-length (FL) transcripts required for normal function remains to be established. Here, we explored BRCA2 exon 3 ( BRCA2 e3) as a model for calibrating variant-induced spliceogenicity and estimating thresholds for BRCA2 haploinsufficiency. In silico predictions, minigene splicing assays, patients' RNA analyses, a mouse embryonic stem cell (mESC) complementation assay and retrieval of patient-related information were combined to determine the minimal requirement of FL BRCA2 transcripts. Of 100 BRCA2 e3 variants tested in the minigene assay, 64 were found to be spliceogenic, causing mild to severe RNA defects. Splicing defects were also confirmed in patients' RNA when available. Analysis of a neutral leaky variant (c.231T>G) showed that a reduction of approximately 60% of FL BRCA2 transcripts from a mutant allele does not cause any increase in cancer risk. Moreover, data obtained from mESCs suggest that variants causing a decline in FL BRCA2 with approximately 30% of wild-type are not pathogenic, given that mESCs are fully viable and resistant to DNA-damaging agents in those conditions. In contrast, mESCs producing lower relative amounts of FL BRCA2 exhibited either null or hypomorphic phenotypes. Overall, our findings are likely to have broader implications on the interpretation of BRCA2 variants affecting the splicing pattern of other essential exons. SIGNIFICANCE: These findings demonstrate that BRCA2 tumor suppressor function tolerates substantial reduction in full-length transcripts, helping to determine the pathogenicity of BRCA2 leaky splicing variants, some of which may not increase cancer risk., (©2020 American Association for Cancer Research.)

This article presents proteomics data referenced in [1] Using proteomics-based evaluation of red blood cells (RBCs), we have identified differentially abundant proteins associated with Obstructive Sleep Apnea Syndrome (OSA). RBCs were collected from peripheral blood of patients with moderate/severe OSA or snoring at pre- (evening) and post-night (morning) polysomnography, so that proteome variations between these time points could be assessed. RBC cytoplasmic fraction depleted of hemoglobin, using Hemovoid ™ system, were analyzed by two-dimensional fluorescence difference gel electrophoresis (2D-DIGE), the 2D image software-based analyzed and relevant differentially abundant proteins identified by mass spectrometry (MS). MS identified 31 protein spots differentially abundant corresponding to 21 unique proteins possibly due to the existence of post-translational modification regulations. Functional analysis by bioinformatics tools indicated that most proteins are associated with catalytic, oxidoreductase, peroxidase, hydrolase, ATPase and anti-oxidant activity. At morning a larger numbers of differential proteins including response to chemical stimulus, oxidation reduction, regulation of catalytic activity and response to stress were observed in OSA. The data might support further research in OSA biomarker discovery and validation.

Uncovering unknown pathological mechanisms and body response to applied medication are the driving forces toward personalized medicine. In this post-genomic era, all eyes are turned to the proteomics field, searching for answers and explanations by investigating the gene end point functional units-proteins and their proteoforms. The development of cutting-edge mass spectrometric technologies and bioinformatics tools have allowed the life-science community to discover disease-specific proteins as biomarkers, which are often concealed by high sample complexity and dynamic range of abundance. Currently, there are several proteomics-based approaches to investigate the proteome. This chapter focuses on gold standard proteomics strategies and related issues toward candidate biomarker discovery, which may have diagnostic/prognostic as well as mechanistic utility in cancer drug resistance.

Only 20-25% of families screened for BRCA1/2 mutations are found positive. Because only a positive result is informative, we studied the role of BRCA1/2 immunohistochemistry as an additional method for patient selection. From 53 high-risk-affected probands, 18 (34%) had available paraffin blocks of their tumors and were selected for this study. Mutation screening was done by conformation-sensitive gel electrophoresis and multiplex ligation-dependent probe amplification. For immunohistochemistry, 21 neoplastic specimens (15 breast carcinomas, 5 ovary neoplasms, and 1 rectal adenocarcinoma) were analyzed with BRCA1 (monoclonal antibody, Ab-1, oncogene) and BRCA2 (polyclonal antibody, Ab-2, oncogene) antibodies. Absence of the BRCA1 protein was confirmed in negative tumors by Western blotting. Seven patients were positive for BRCA1/2 mutations: 5 for BRCA1 and 2 for BRCA2. Four out of five positive patients had tumors negative for BRCA1 immunostaining, and the remaining 13 BRCA1-negative patients had positive BRCA1 immunostaining in all tumor samples. Sensitivity to predict for BRCA1 mutation carriers was 80%, and specificity was 100%, with a positive predictive value of 100% and a negative predictive value of 93%. This correlation was statistically significant (p=0.001). No correlation was observed for BRCA2. If larger studies confirm these results, high-risk patients with BRCA1-negative tumors should be screened first for this gene.

Purpose: BRCA2 rearrangements are rare genetic events. A large BRCA2 genomic insertion was recurrently observed in our participants, and we sought to characterize it at the molecular and phenotypic level., Patients and Methods: We studied 210 high-risk breast/ovarian cancer families. Fifty-three probands were fully screened for BRCA1/2 mutations, and three of 53 had a large insertion in exon 3 of BRCA2. This finding was analyzed by polymerase chain reaction (PCR), reverse transcriptase PCR (RT-PCR), and sequencing. An additional 157 consecutive families were screened for this mutation by a three-step PCR method. Phenotype and haplotype analysis was also performed., Results: Sixteen BRCA mutations were observed in 19 of 53 patients (36% detection rate). A recurrent Alu motif insertion in position c.156&#95;157 was observed after sequencing of an abnormal fragment obtained after the amplification of BRCA2 exon 3. RT-PCR revealed exon 3 skipping. Screening of this rearrangement identified 14 additional families (out of 157). In total, 17 (8%) of 210 high-risk families ascertained in our clinic were positive for this mutation. Segregation of a common haplotype (from D13S260 to D13S1695) confirmed a common origin, estimated to have occurred 2,400 to 2,600 years ago. The following four cancer phenotypes were observed in the 17 positive families: female breast (n = 9), male breast (n = 4), breast/ovarian (n = 2), and heterogeneous (n = 2). Male breast cancer was more frequently observed in c.156&#95;157insAlu-positive families compared with negative families (23% v 12%, respectively), and 33% of all male breast cancer families with an identified BRCA mutation were c.156&#95;157insAlu positive., Conclusion: c.156&#95;157insAlu is a founder mutation of Portuguese origin and is the most frequent BRCA2 rearrangement described to date.