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Malignant pleural mesothelioma (MPM) is a tumour associated with asbestos exposure. Approximately, 10% of patients with MPM carry a germline pathogenic variant (PV), mostly in DNA repair genes, suggesting the occurrence of inherited predispositions.This article aimed to 1) search for new predisposing genes and assess the prevalence of PVs in DNA repair genes, by next-generation sequencing (NGS) analysis of germline DNA from 113 unselected patients with MPM and 2) evaluate whether these patients could be sensitive to tailored treatments.NGS was performed using a custom panel of 107 cancer-predisposing genes. To investigate the response to selected drugs in conditions of DNA repair insufficiency, we created a three-dimensional-MPM cell model that had a defect in ataxia telangiectasia mutated (ATM), the master regulator of DNA repair.We identified PVs in approximately 7% of patients with MPM (8/113) and a new PV in BAP1 in a further patient with familial MPM. Most of these PVs were in genes involved or supposedly involved in DNA repair (BRCA1, BRIP1, CHEK2, SLX4, FLCN and BAP1). In vitro studies showed apoptosis induction in ATM-silenced/inhibited MPM spheroids treated with an enhancer of zeste homologue 2 inhibitor (tazemetostat).Overall these data suggest that patients with MPM and DNA repair insufficiency may benefit from this treatment, which induces synthetic lethality.

Malignant pleural mesothelioma (MPM) is a rare and aggressive cancer mainly caused by asbestos exposure. Specific and sensitive non-invasive biomarkers may facilitate and enhance screening programs for the early detection of cancer. We investigated DNA methylation (DNAm) profiles in MPM pre-diagnostic blood samples in a case-control study nested in the European Prospective Investigation into Cancer and nutrition (EPIC) cohort, aiming to characterise DNAm biomarkers associated with MPM. From the EPIC cohort, we included samples from 135 participants who developed MPM during 20 years of follow up and from 135 matched, cancer-free, controls. For the discovery phase we selected EPIC participants who developed MPM within five years from enrolment (n=36) with matched controls. We identified nine differentially methylated CpGs, selected by 10-fold cross-validation and correlation analyses: cg25755428 (MRI1), cg20389709 (KLF11), cg23870316, cg13862711 (LHX6), cg06417478 (HOOK2), cg00667948, cg01879420 (AMD1), cg25317025 (RPL17) and cg06205333 (RAP1A). Receiver operating characteristic (ROC) analysis showed that the model including baseline characteristics (age, sex, PC1wbc) along with the nine MPM-related CpGs has a better predictive value for MPM occurrence than the baseline model alone, maintaining some performance also at more than five years before diagnosis [AUC (area under the curve) 10 years=0.75; baseline AUC range=0.63-0.67)]. DNAm changes as non-invasive biomarkers in pre-diagnostic blood samples of MPM cases were investigated for the first time. Their application can improve the identification of asbestos-exposed individuals at higher MPM risk in order to possibly adopt more intensive monitoring for early disease identification.

To reconstruct the phenotypical and clinical implications of the Italian genetic structure, we thoroughly analyzed a whole-exome sequencing data set comprised of 1686 healthy Italian individuals. We found six previously unreported variants with remarkable frequency differences between Northern and Southern Italy in the HERC2, OR52R1, ADH1B, and THBS4 genes. We reported 36 clinically relevant variants (submitted as pathogenic, risk factors, or drug response in ClinVar) with significant frequency differences between Italy and Europe. We then explored putatively pathogenic variants in the Italian exome. On average, our Italian individuals carried 16.6 protein-truncating variants (PTVs), with 2.5% of the population having a PTV in one of the 59 American College of Medical Genetics (ACMG) actionable genes. Lastly, we looked for PTVs that are likely to cause Mendelian diseases. We found four heterozygous PTVs in haploinsufficient genes (KAT6A, PTCH1, and STXBP1) and three homozygous PTVs in genes causing recessive diseases (DPYD, FLG, and PYGM). Comparing frequencies from our data set to other public databases, like gnomAD, we showed the importance of population-specific databases for a more accurate assessment of variant pathogenicity. For this reason, we made aggregated frequencies from our data set publicly available as a tool for both clinicians and researchers (http://nigdb.cineca.it; NIG-ExIT).

Simple Summary Malignant pleural mesothelioma (MPM) is an aggressive and still incurable cancer. There is an urgent need to identify effective and reliable tools for detecting and diagnosing the early onset of MPM. In our study, we investigated the whole miRNAs expression profile from serum extracellular vesicles to identify early changes related to MPM development. miR-11400, miR-148a-3p, and miR-409-3p levels were increased in pre-clinical MPM patients up to five years before their diagnosis. The three-miRNA pattern showed a good discrimination capacity to distinguish pre-clinical MPM from cancer-free controls. The three miRNAs also displayed high diagnostic capabilities for differentiating between MPM patients and controls. This study identified a potential EV miRNA signature in preclinical MPM up to five years before diagnosis and raises the possibility of early intervention. Malignant pleural mesothelioma (MPM) is an aggressive cancer with a dismal prognosis. Early therapeutic interventions could improve patient outcomes. We aimed to identify a pattern of microRNAs (miRNAs) as potential early non-invasive markers of MPM. In a case-control study nested in the European Prospective Investigation into Cancer and Nutrition cohort, we screened the whole miRNome in serum extracellular vesicles (EVs) of preclinical MPM cases. In a subgroup of 20 preclinical samples collected five years prior MPM diagnosis, we observed an upregulation of miR-11400 (fold change (FC) = 2.6, adjusted p-value = 0.01), miR-148a-3p (FC = 1.5, p-value = 0.001), and miR-409-3p (FC = 1.5, p-value = 0.04) relative to matched controls. The 3-miRNA panel showed a good classification capacity with an area under the receiver operating characteristic curve (AUC) of 0.81 (specificity = 0.75, sensitivity = 0.70). The diagnostic ability of the model was also evaluated in an independent retrospective cohort, yielding a higher predictive power (AUC = 0.86). A signature of EV miRNA can be detected up to five years before MPM; moreover, the identified miRNAs could provide functional insights into the molecular changes related to the late carcinogenic process, preceding MPM development.

The KMT2A/AFF1 rearrangement is associated with an unfavorable prognosis in infant acute lymphocytic leukemia (ALL). Discordant ALL in monozygotic twins is uncommon and represents an attractive resource to evaluate intrauterine environment–genetic interplay in ALL. Mutational and epigenetic profiles were characterized for a discordant KMT2A/AFF1-rearranged infant monozygotic twin pair and their parents, and they were compared to three independent KMT2A/AFF1-positive ALL infants, in which the DNA methylation and gene expression profiles were investigated. A de novo Q61H NRAS mutation was detected in the affected twin at diagnosis and backtracked in both twins at birth. The KMT2A/AFF1 rearrangement was absent at birth in both twins. Genetic analyses conducted at birth gave more insights into the timing of the mutation hit. We identified correlations between DNA methylation and gene expression changes for 32 genes in the three independent affected versus remitted patients. The strongest correlations were observed for the RAB32, PDK4, CXCL3, RANBP17, and MACROD2 genes. This epigenetic signature could be a putative target for the development of novel epigenetic-based therapies and could help in explaining the molecular mechanisms characterizing ALL infants with KMT2A/AFF1 fusions.

Malignant pleural mesothelioma (MPM) is a rare and aggressive neoplasm. Patients are usually diagnosed when current treatments have limited benefits, highlighting the need for noninvasive tests aimed at an MPM risk assessment tool that might improve life expectancy. Three hundred asbestos-exposed subjects (163 MPM cases and 137 cancer-free controls), from the same geographical region in Italy, were recruited. The evaluation of asbestos exposure was conducted considering the frequency, the duration and the intensity of occupational, environmental and domestic exposure. A genome-wide methylation array was performed to identify novel blood DNA methylation (DNAm) markers of MPM. Multiple regression analyses adjusting for potential confounding factors and interaction between asbestos exposure and DNAm on the MPM odds ratio were applied. Epigenome-wide analysis (EWAS) revealed 12 single-CpGs associated with the disease. Two of these showed high statistical power (99%) and effect size (&gt, 0.05) after false discovery rate (FDR) multiple comparison corrections: (i) cg03546163 in FKBP5, significantly hypomethylated in cases (Mean Difference in beta values (MD) = −0.09, 95% CI = −0.12|−0.06, p = 1.2 × 10−7), and (ii) cg06633438 in MLLT1, statistically hypermethylated in cases (MD = 0.07, 95% CI = 0.04|0.10, p = 1.0 × 10−6). Based on the interaction analysis, asbestos exposure and epigenetic profile together may improve MPM risk assessment. Above-median asbestos exposure and hypomethylation of cg03546163 in FKBP5 (OR = 20.84, 95% CI = 8.71|53.96, p = 5.5 × 10−11) and hypermethylation of cg06633438 in MLLT1 (OR = 11.71, 95% CI = 4.97|29.64, p = 5.9 × 10−8) genes compared to below-median asbestos exposure and hyper/hypomethylation of single-CpG DNAm, respectively. Receiver Operation Characteristics (ROC) for Case-Control Discrimination showed a significant increase in MPM discrimination when DNAm information was added in the model (baseline model, BM: asbestos exposure, age, gender and white blood cells), area under the curve, AUC = 0.75, BM + cg03546163 at FKBP5. AUC = 0.89, 2.1 × 10−7, BM + cg06633438 at MLLT1. AUC = 0.89, 6.3 × 10−8. Validation and replication procedures, considering independent sample size and a different DNAm analysis technique, confirmed the observed associations. Our results suggest the potential application of DNAm profiles in blood to develop noninvasive tests for MPM risk assessment in asbestos-exposed subjects.

Simple Summary Our study is the first one to investigate DNA methylation changes in white blood cells (WBCs) from easily accessible peripheral blood as malignant pleural mesothelioma (MPM) survival biomarker. The Cox proportional hazards regression model highlighted that the methylation status of the CpG dinucleotide cg03546163 is an independent marker of prognosis in MPM patients with a better performance than traditional inflammation-based scores such as lymphocyte-to-monocyte ratio (LMR). Biological validation and replication showed that epigenetic changes at the FKBP5 gene were robustly associated with overall survival (OS) in MPM cases. The identification of simple and valuable prognostic markers for MPM will enable clinicians to select patients who are most likely to benefit from aggressive therapies and avoid subjecting non-responder patients to ineffective treatment. Abstract Malignant pleural mesothelioma (MPM) is an aggressive tumor with median survival of 12 months and limited effective treatments. The scope of this study was to study the relationship between blood DNA methylation (DNAm) and overall survival (OS) aiming at a noninvasive prognostic test. We investigated a cohort of 159 incident asbestos exposed MPM cases enrolled in an Italian area with high incidence of mesothelioma. Considering 12 months as a cut-off for OS, epigenome-wide association study (EWAS) revealed statistically significant (p value = 7.7 × 10−9) OS-related differential methylation of a single-CpG (cg03546163), located in the 5′UTR region of the FKBP5 gene. This is an independent marker of prognosis in MPM patients with a better performance than traditional inflammation-based scores such as lymphocyte-to-monocyte ratio (LMR). Cases with DNAm < 0.45 at the cg03546163 had significantly poor survival compared with those showing DNAm ≥ 0.45 (mean: 243 versus 534 days; p value< 0.001). Epigenetic changes at the FKBP5 gene were robustly associated with OS in MPM cases. Our results showed that blood DNA methylation levels could be promising and dynamic prognostic biomarkers in MPM.

Malignant pleural mesothelioma (MPM) is an aggressive tumor with median survival of 12 months and limited effective treatments. The scope of this study was to study the relationship between blood DNA methylation (DNAm) and overall survival (OS) aiming at a noninvasive prognostic test. We investigated a cohort of 159 incident asbestos exposed MPM cases enrolled in an Italian area with high incidence of mesothelioma. Considering 12 months as a cut-off for OS, epigenome-wide association study (EWAS) revealed statistically significant (p value = 7.7 &times, 10&minus, 9) OS-related differential methylation of a single-CpG (cg03546163), located in the 5&prime, UTR region of the FKBP5 gene. This is an independent marker of prognosis in MPM patients with a better performance than traditional inflammation-based scores such as lymphocyte-to-monocyte ratio (LMR). Cases with DNAm &lt, 0.45 at the cg03546163 had significantly poor survival compared with those showing DNAm &ge, 0.45 (mean: 243 versus 534 days, p value&lt, 0.001). Epigenetic changes at the FKBP5 gene were robustly associated with OS in MPM cases. Our results showed that blood DNA methylation levels could be promising and dynamic prognostic biomarkers in MPM.

The definition of the mesothelioma genome is expected to have a great impact toward the development of new drugs and therapeutic approaches with a view to precision medicine. A few studies reported that the malignant pleural mesothelioma (MPM) genomic landscape is characterized by a much greater number of genomic losses than point mutations. Inactivating gene fusions, copy losses, and protein-truncating variants (PTVs) mostly affect tumor suppressor genes, above all BAP1, NF2, CDKN2A, and SETD2. Some of them may be exploited to design novel therapeutic strategies. Germline mutations in some of these genes represent MPM-predisposing risk factors. These mutations require a second hit, i.e., asbestos exposure, to induce carcinogenesis. The most studied of these genes is BAP1. Germline mutations in other tumor suppressor genes, mostly involved in DNA repair, have also been identified in about 10% of MPM patients. These patients are more sensitive to asbestos exposure than those who do not carry such mutations and may benefit of specific treatments. Additionally, epigenetic mechanisms, such as methylation or miRNA alterations, may modify gene expression and drive carcinogenesis. The same abnormalities may be used as disease biomarkers or therapeutic targets.

Introduction Malignant pleural mesothelioma (MPM) is an aggressive tumor strongly associated with asbestos exposure. Patients are usually diagnosed when current treatments have limited benefits, highlighting the need for noninvasive early diagnostic tests to monitor asbestos-exposed people. Methods We used a genome-wide methylation array to identify, in asbestos-exposed subjects, novel blood DNA methylation markers of MPM in 163 MPM cases and 137 cancer-free controls (82 MPM cases and 68 controls, training set; replication in 81 MPM cases and 69 controls, test set) sampled from the same areas. Results Evidence of differential methylation between MPM cases and controls was found (more than 800 cytosine-guanine dinucleotide sites, false discovery rate p value (pfdr) Conclusions We identified signatures of differential methylation in DNA from whole blood between asbestos exposed MPM cases and controls. Our results provide the rationale to further investigate, in prospective studies, the potential use of blood DNA methylation profiles for the identification of early changes related to the MPM carcinogenic process.

The role of rare variants in complex traits remains uncharted. Here, we conduct deep whole genome sequencing of 1457 individuals from an isolated population, and test for rare variant burdens across six cardiometabolic traits. We identify a role for rare regulatory variation, which has hitherto been missed. We find evidence of rare variant burdens that are independent of established common variant signals (ADIPOQ and adiponectin, P = 4.2 × 10−8; APOC3 and triglyceride levels, P = 1.5 × 10−26), and identify replicating evidence for a burden associated with triglyceride levels in FAM189B (P = 2.2 × 10−8), indicating a role for this gene in lipid metabolism., Rare genetic variants can contribute to complex traits but this contribution is not well understood. Here, the authors analyse deep whole genome sequencing data across 1457 individuals from an isolated Greek population and find association of rare variant burdens with cardiometabolic traits.

Pathogenic germline variants in the BAP1 tumor suppressor gene can cause a cancer syndrome called BAP1 tumor predisposition syndrome (BAP1-TPDS), which is characterized by predisposition to mesothelioma, melanoma, renal cell carcinoma, basal cell carcinoma, and other tumors. Other genes that may predispose to mesothelioma are CDKN2A and DNA repair genes. Asbestos exposure has often been reported in patients with malignant pleural mesothelioma (MPM) and germline variants in BAP1, but this exposure has never been quantified. We aimed to search for germline variants in BAP1 among 25 new Italian probands with suspected BAP1-TPDS, summarize the prevalence of these variants in 39 Italian patients with familial MPM and other tumors recruited over a 5-year period, and compare cumulative asbestos exposure in 14 patients with MPM and pathogenic germline variants in BAP1, CDKN2A, or DNA repair genes with that of 67 patients without germline variants in 94 cancer-predisposing genes. We report here a new pathogenic germline variant in BAP1: c.783 + 2 T > C. The prevalence of pathogenic germline variants in BAP1 was 7.7% among patients with familial MPM (3/39). Patients with pathogenic germline variants in BAP1, CDKN2A, or DNA repair genes showed lower cumulative asbestos exposure than patients without germline variants in 94 cancer-predisposing genes (P = .00002). This suggests an interaction between genetic risk factors and asbestos in the development of mesothelioma.

Occupational and environmental asbestos exposure is the main determinant of malignant pleural mesothelioma (MPM), however, the mechanisms by which its fibres contribute to cell toxicity and transformation are not completely clear. Aberrant DNA methylation is a common event in cancer but epigenetic modifications involved specifically in MPM carcinogenesis need to be better clarified. To investigate asbestos-induced DNA methylation and gene expression changes, we treated Met5A mesothelial cells with different concentrations of crocidolite and chrysotile asbestos (0.5 ÷ 5.0 µg/cm2, 72 h incubation). Overall, we observed 243 and 302 differentially methylated CpGs (≥ 10%) between the asbestos dose at 5 µg/cm2 and untreated control, in chrysotile and crocidolite treatment, respectively. To examine the dose–response effect, Spearman’s correlation test was performed and significant CpGs located in genes involved in migration/cell adhesion processes were identified in both treatments. Moreover, we found that both crocidolite and chrysotile exposure induced a significant up-regulation of CA9 and SRGN (log2 fold change > 1.5), previously reported as associated with a more aggressive MPM phenotype. However, we found no correlation between methylation and gene expression changes, except for a moderate significant inverse correlation at the promoter region of DKK1 (Spearman rho = − 1, P value = 0.02) after chrysotile exposure. These results describe for the first time the relationship between DNA methylation modifications and asbestos exposure. Our findings provide a basis to further explore and validate asbestos-induced DNA methylation changes, that could influence MPM carcinogenesis and possibly identifying new chemopreventive target.

Objectives Osteoarthritis (OA) is a complex disease, but its genetic aetiology remains poorly characterised. To identify novel susceptibility loci for OA, we carried out a genome-wide association study (GWAS) in individuals from the largest UK-based OA collections to date. Methods We carried out a discovery GWAS in 5414 OA individuals with knee and/or hip total joint replacement (TJR) and 9939 population-based controls. We followed-up prioritised variants in OA subjects from the interim release of the UK Biobank resource (up to 12 658 cases and 50 898 controls) and our lead finding in operated OA subjects from the full release of UK Biobank (17 894 cases and 89 470 controls). We investigated its functional implications in methylation, gene expression and proteomics data in primary chondrocytes from 12 pairs of intact and degraded cartilage samples from patients undergoing TJR. Results We detect a genome-wide significant association at rs10116772 with TJR (P=3.7×10−8; for allele A: OR (95% CI) 0.97 (0.96 to 0.98)), an intronic variant in GLIS3, which is expressed in cartilage. Variants in strong correlation with rs10116772 have been associated with elevated plasma glucose levels and diabetes. Conclusions We identify a novel susceptibility locus for OA that has been previously implicated in diabetes and glycaemic traits.

Inherited loss-of-function mutations in the BAP1 oncosuppressor gene are responsible for an inherited syndrome with predisposition to malignant mesothelioma (MM), uveal and keratinocytic melanoma, and other malignancies. Germline mutations that were inherited in an autosomal dominant fashion were identified in nine families with multiplex MM cases and 25 families with multiple melanoma, renal cell carcinoma, and other tumors. Germline mutations were also identified in sporadic MM cases, suggesting that germline mutations in BAP1 occur frequently. In this article, we report the analysis of BAP1 in five multiplex MM families and in 103 sporadic cases of MM. One family carried a new truncating germline mutation. Using immunohistochemistry, we show that BAP1 is not expressed in tumor tissue, which is in accordance with Knudson's two hits hypothesis. Interestingly, whereas the three individuals who were possibly exposed to asbestos developed MM, the individual who was not exposed developed a different tumor type, that is, mucoepidermoid carcinoma. This finding suggests that the type of carcinogen exposure may be important for the cancer type that is developed by mutation carriers. On the contrary, the other families or the 103 sporadic patients did not show germline mutations in BAP1. Our data show that BAP1 mutations are very rare in patients with sporadic MM, and we report a new BAP1 mutation, extend the cancer types associated with these mutations, and suggest the existence of other yet unknown genes in the pathogenesis of familial MM.

BAP1 germline mutations predispose to a cancer predisposition syndrome that includes mesothelioma, cutaneous melanoma, uveal melanoma and other cancers. This co-occurrence suggests that these tumors share a common carcinogenic pathway. To evaluate this hypothesis, we studied 40 Italian families with mesothelioma and/or melanoma. The probands were sequenced for BAP1 and for the most common melanoma predisposition genes (i.e. CDKN2A, CDK4, TERT, MITF and POT1) to investigate if these genes may also confer susceptibility to mesothelioma. In two out of six families with both mesothelioma and melanoma we identified either a germline nonsense mutation (c.1153C > T, p.Arg385*) in BAP1 or a recurrent pathogenic germline mutation (c.301G > T, p.Gly101Trp) in CDKN2A. Our study suggests that CDKN2A, in addition to BAP1, could be involved in the melanoma and mesothelioma susceptibility, leading to the rare familial cancer syndromes. It also suggests that these tumors share key steps that drive carcinogenesis and that other genes may be involved in inherited predisposition to malignant mesothelioma and melanoma.

Asbestos exposure is the main risk factor for malignant pleural mesothelioma (MPM), a rare aggressive tumor. Nevertheless, on average less than 10% of subjects highly exposed to asbestos develop MPM, suggesting the possible involvement of other risk factors. To identify the genetic factors that may modulate the risk of MPM, we conducted a gene-environment interaction analysis including asbestos exposure and 15 single nucleotide polymorphisms (SNPs) previously identified through a genome-wide association study on Italian subjects. In the present study, we assessed gene-asbestos interaction on MPM risk using relative excess risk due to interaction and synergy index for additive interaction and V index for multiplicative interaction. Generalized multifactor dimensionality reduction (GMDR) analyses were also performed. Positive deviation from additivity was found for six SNPs (rs1508805, rs2501618, rs4701085, rs4290865, rs10519201, rs763271), and four of them (rs1508805, rs2501618, rs4701085, rs10519201) deviated also from multiplicative models. However, after Bonferroni correction, deviation from multiplicative model was still significant for rs1508805 and rs4701085 only. GMDR analysis showed a strong MPM risk due to asbestos exposure and suggested a possible synergistic effect between asbestos exposure and rs1508805, rs2501618 and rs5756444. Our results suggested that gene-asbestos interaction may play an additional role on MPM susceptibility, given that asbestos exposure appears as the main risk factor.

Inherited loss-of-function mutations in the BAP1 oncosuppressor gene are responsible for an inherited syndrome with predisposition to malignant mesothelioma (MM), uveal and keratinocytic melanoma, and other malignancies. Germline mutations that were inherited in an autosomal dominant fashion were identified in nine families with multiplex MM cases and 25 families with multiple melanoma, renal cell carcinoma, and other tumors. Germline mutations were also identified in sporadic MM cases, suggesting that germline mutations in BAP1 occur frequently. In this article, we report the analysis of BAP1 in five multiplex MM families and in 103 sporadic cases of MM. One family carried a new truncating germline mutation. Using immunohistochemistry, we show that BAP1 is not expressed in tumor tissue, which is in accordance with Knudson's two hits hypothesis. Interestingly, whereas the three individuals who were possibly exposed to asbestos developed MM, the individual who was not exposed developed a different tumor type, that is, mucoepidermoid carcinoma. This finding suggests that the type of carcinogen exposure may be important for the cancer type that is developed by mutation carriers. On the contrary, the other families or the 103 sporadic patients did not show germline mutations in BAP1. Our data show that BAP1 mutations are very rare in patients with sporadic MM, and we report a new BAP1 mutation, extend the cancer types associated with these mutations, and suggest the existence of other yet unknown genes in the pathogenesis of familial MM.