Familial malignant mesothelioma: a population-based study in central Italy (1980-2012)

The role of single nucleotide polymorphisms related to iron homeostasis in mesothelioma susceptibility after asbestos exposure: a genetic study on autoptic samples

Asbestos-related diseases still represent a major public health problem all over the world. Among them, malignant mesothelioma (MM) is a poor-prognosis cancer, arising from the serosal lining of the pleura, pericardium and peritoneum, triggered by asbestos exposure. Literature data suggest the key role of iron metabolism in the coating process leading to the formation of asbestos bodies, considered to be both protective and harmful. Two sample sets of individuals were taken into consideration, both residing in Broni or neighboring cities (Northwestern Italy) where an asbestos cement factory was active between 1932 and 1993. The present study aims to compare the frequency of six SNPs involved in iron trafficking, previously found to be related to protection/predisposition to MM after asbestos exposure, between 48 male subjects with documented asbestos exposure who died of MM and 48 male subjects who were exposed to asbestos but did not develop MM or other neoplastic respiratory diseases (Non-Mesothelioma Asbestos Exposed - NMAE). The same analysis was performed on 76 healthy male controls. The allelic and genotypic frequencies of a sub-group of 107 healthy Italian individuals contained in the 1000 genomes database were considered for comparison. PCR-multiplex amplification followed by SNaPshot mini-sequencing reaction was used. The findings presented in this study show that the allelic and genotypic frequencies for six SNP markers involved in iron metabolism/homeostasis and the modulation of tumor microenvironment are not significantly different between the two sample sets of MM and NMAE. Therefore, the SNPs here considered do not seem to be useful markers for individual susceptibility to mesothelioma. This finding is not in agreement with previous literature.

An Approach to Overcome the Limitations of Surveillance of Asbestos Related Diseases in Low- and Middle-Income Countries: What We Learned from the Sibaté Study in Colombia

Introduction

The asbestos industry began its operations in Colombia in 1942 with the establishment of an asbestos-cement facility in Sibaté, located in the Department of Cundinamarca. Despite extensive asbestos use and production in Colombia, the country lacks a reliable epidemiological surveillance system to monitor the health effects of asbestos exposure. The Colombian health information system, known as SISPRO, did not report mesothelioma cases diagnosed in the municipality, posing a significant challenge in understanding the health impacts of asbestos exposure on the population of Sibaté.

Methods

To address this issue, an active surveillance strategy was implemented in Sibaté. This strategy involved conducting door-to-door health and socioeconomic structured interviews to identify Asbestos-Related Diseases (ARDs). Validation strategies included a thorough review of medical records by a panel of physicians, and the findings were communicated to local, regional, and national authorities, as well as the general population.

Results

The active surveillance strategy successfully identified a mesothelioma cluster in Sibaté, revealing the inadequacy of the existing health information system in monitoring asbestos-related diseases. The discovery of this cluster underscores the critical importance of implementing active surveillance strategies in Colombia, where governmental institutions and resources are often limited.

Conclusion

The findings of this study emphasize the urgent need for Colombia to establish a reliable epidemiological surveillance system for asbestos-related diseases (ARDs). Active surveillance strategies can play a crucial role in identifying mesothelioma clusters and enhancing our understanding of the health effects of asbestos exposure in low- and middle-income countries.

The Role of Germline Mutations in Thoracic Malignancies: Between Myth and Reality

Considering the established contribution of environmental factors to the development of thoracic malignancies, the inherited susceptibility of these tumors has rarely been explored. However, the recent introduction of next-generation sequencing-based tumor molecular profiling in the real-word setting enabled us to deeply characterize the genomic background of patients with lung cancer with or without smoking-related history, increasing the likelihood of detecting germline mutations with potential prevention and treatment implications. Pathogenic germline variants have been detected in 2% to 3% of patients with NSCLC undergoing next-generation sequencing analysis, whereas the proportion of germline mutations associated with the development of pleural mesothelioma widely varies across different studies, ranging between 5% and 10%. This review provides an updated summary of emerging evidence about germline mutations in thoracic malignancies, focusing on pathogenetic mechanisms, clinical features, therapeutic implications, and screening recommendations for high-risk individuals.

Silencing VDAC1 to Treat Mesothelioma Cancer: Tumor Reprograming and Altering Tumor Hallmarks

Mesothelioma, an aggressive cancer with a poor prognosis, is linked to asbestos exposure. However, carbon nanotubes found in materials we are exposed to daily can cause mesothelioma cancer. Cancer cells reprogram their metabolism to support increased biosynthetic and energy demands required for their growth and motility. Here, we examined the effects of silencing the expression of the voltage-dependent anion channel 1 (VDAC1), controlling the metabolic and energetic crosstalk between mitochondria and the rest of the cell. We demonstrate that VDAC1 is overexpressed in mesothelioma patients; its levels increase with disease stage and are associated with low survival rates. Silencing VDAC1 expression using a specific siRNA identifying both mouse and human VDAC1 (si-m/hVDAC1-B) inhibits cell proliferation of mesothelioma cancer cells. Treatment of xenografts of human-derived H226 cells or mouse-derived AB1 cells with si-m/hVDAC1-B inhibited tumor growth and caused metabolism reprogramming, as reflected in the decreased expression of metabolism-related proteins, including glycolytic and tricarboxylic acid (-)cycle enzymes and the ATP-synthesizing enzyme. In addition, tumors depleted of VDAC1 showed altered microenvironments and inflammation, both associated with cancer progression. Finally, tumor VDAC1 silencing also eliminated cancer stem cells and induced cell differentiation to normal-like cells. The results show that silencing VDAC1 expression leads to reprogrammed metabolism and to multiple effects from tumor growth inhibition to modulation of the tumor microenvironment and inflammation, inducing differentiation of malignant cells. Thus, silencing VDAC1 is a potential therapeutic approach to treating mesothelioma.

GOECP/SEOR clinical guidelines on radiotherapy for malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rare tumor with poor prognosis and rising incidence. Palliative care is common in MPM as radical treatment with curative intent is often not possible due to metastasis or extensive locoregional involvement. Numerous therapeutic advances have been made in recent years, including the use of less aggressive surgical techniques associated with lower morbidity and mortality (e.g., pleurectomy/decortication), technological advancements in the field of radiotherapy (intensity-modulated radiotherapy, image-guided radiotherapy, stereotactic body radiotherapy, proton therapy), and developments in systemic therapies (chemotherapy and immunotherapy). These improvements have had as yet only a modest effect on local control and survival. Advances in the management of MPM and standardization of care are hampered by the evidence to date, limited by high heterogeneity among studies and small sample sizes. In this clinical guideline prepared by the oncological group for the study of lung cancer of the Spanish Society of Radiation Oncology, we review clinical, histologic, and therapeutic aspects of MPM, with a particular focus on all aspects relating to radiotherapy, including the current evidence base, associations with chemotherapy and surgery, treatment volumes and planning, technological advances, and reradiation.

ERS/ESTS/EACTS/ESTRO guidelines for the management of malignant pleural mesothelioma

The European Respiratory Society (ERS)/European Society of Thoracic Surgeons (ESTS)/European Association for Cardio-Thoracic Surgery (EACTS)/European Society for Radiotherapy and Oncology (ESTRO) task force brought together experts to update previous 2009 ERS/ESTS guidelines on management of malignant pleural mesothelioma (MPM), a rare cancer with globally poor outcome, after a systematic review of the 2009-2018 literature. The evidence was appraised using the Grading of Recommendations, Assessment, Development and Evaluation approach. The evidence syntheses were discussed and recommendations formulated by this multidisciplinary group of experts. Diagnosis: pleural biopsies remain the gold standard to confirm the diagnosis, usually obtained by thoracoscopy but occasionally via image-guided percutaneous needle biopsy in cases of pleural symphysis or poor performance status. Pathology: standard staining procedures are insufficient in ∼10% of cases, justifying the use of specific markers, including BAP-1 and CDKN2A (p16) for the separation of atypical mesothelial proliferation from MPM. Staging: in the absence of a uniform, robust and validated staging system, we advise using the most recent 2016 8th TNM (tumour, node, metastasis) classification, with an algorithm for pretherapeutic assessment. Monitoring: patient's performance status, histological subtype and tumour volume are the main prognostic factors of clinical importance in routine MPM management. Other potential parameters should be recorded at baseline and reported in clinical trials. Treatment: (chemo)therapy has limited efficacy in MPM patients and only selected patients are candidates for radical surgery. New promising targeted therapies, immunotherapies and strategies have been reviewed. Because of limited data on the best combination treatment, we emphasize that patients who are considered candidates for a multimodal approach, including radical surgery, should be treated as part of clinical trials in MPM-dedicated centres.

ERS/ESTS/EACTS/ESTRO guidelines for the management of malignant pleural mesothelioma

The European Respiratory Society (ERS)/European Society of Thoracic Surgeons (ESTS)/European Association for Cardio-Thoracic Surgery (EACTS)/European Society for Radiotherapy and Oncology (ESTRO) task force brought together experts to update previous 2009 ERS/ESTS guidelines on management of malignant pleural mesothelioma (MPM), a rare cancer with globally poor outcome, after a systematic review of the 2009-2018 literature. The evidence was appraised using the Grading of Recommendations, Assessment, Development and Evaluation approach. The evidence syntheses were discussed and recommendations formulated by this multidisciplinary group of experts. Diagnosis: pleural biopsies remain the gold standard to confirm the diagnosis, usually obtained by thoracoscopy but occasionally via image-guided percutaneous needle biopsy in cases of pleural symphysis or poor performance status. Pathology: standard staining procedures are insufficient in ∼10% of cases, justifying the use of specific markers, including BAP-1 and CDKN2A (p16) for the separation of atypical mesothelial proliferation from MPM. Staging: in the absence of a uniform, robust and validated staging system, we advise using the most recent 2016 8th TNM (tumour, node, metastasis) classification, with an algorithm for pre-therapeutic assessment. Monitoring: patient's performance status, histological subtype and tumour volume are the main prognostic factors of clinical importance in routine MPM management. Other potential parameters should be recorded at baseline and reported in clinical trials. Treatment: (chemo)therapy has limited efficacy in MPM patients and only selected patients are candidates for radical surgery. New promising targeted therapies, immunotherapies and strategies have been reviewed. Because of limited data on the best combination treatment, we emphasise that patients who are considered candidates for a multimodal approach, including radical surgery, should be treated as part of clinical trials in MPM-dedicated centres.

[Malignant mesothelioma and constitutional BAP1 gene mutations]

Malignant mesothelioma is a rare tumour, usually the result of asbestos exposure. Several cases of familial aggregation have been reported and recently shown to be associated with constitutional mutations of the BAP1 gene. BAP1 is a deubiquitinating enzyme implicated in several different cellular mechanisms such as the repair or differentiation of DNA. About a half of malignant mesotheliomas present a somatic, bi-allelic inactivation of BAP1, demonstrated by nuclear extinction on histochemistry. Constitutional alterations of BAP1 are extremely rare. Present in the heterozygous state they are transmitted as an autosomal dominant. They are associated with a risk of developing other tumours such as uveal and cutaneous melanomas, benign melanocytic tumours (melanocytic BAP1-mutated atypical intradermal tumour or MBAITS) and clear cell renal carcinomas. The causal link between mesothelioma and germinal mutations of BAP1 has still not been clearly identified. At present there is, in France, no consensus on recommendations for the management of patients with these mutations. This article is a synthesis of the literature on the functions of the BAP1 gene, the tumour risks related to its alteration and the follow up of patients bearing a constitutional mutation.

Familial risk of pleural mesothelioma increased drastically in certain occupations: A nationwide prospective cohort study

OBJECTIVE

We aimed to explore the effect of occupation on familial risk of pleural mesothelioma in a nationwide cohort study design.

METHOD

The nationwide Swedish Family-Cancer Database includes all Swedes born after 1931 and their biological parents, totalling 16.1 million individuals with about 2.3 million cancer patients. Hazards ratios (HRs) were calculated adjusting for age, sex and region of residence.

RESULTS

Having asbestos-related occupation in the absence of family history of mesothelioma increased risk of mesothelioma more than threefold (adjusted HR = 3.2, 95% confidence interval [CI]: 3.0-3.5). In those who had a history of mesothelioma in their first-degree relatives and an asbestos-related occupation, risk of mesothelioma dramatically increased compared with individuals without such occupations and family history (without chronic obstructive pulmonary disease [COPD] HR = 24, 95% CI: 15-39; with COPD 45, 95% CI: 15-141). In those who had a family history of mesothelioma and no history of an asbestos-related occupation, risk of mesothelioma did not show significant increase compared with those who had no family history of mesothelioma and no asbestos-related occupation (HR = 1.6; 95% CI: 0.7-3.8).

CONCLUSION

First-degree relatives of patients with pleural mesothelioma had a drastic risk of developing this malignancy in case of certain occupations, which shows a gene-environment interaction is probable in risk of mesothelioma.

Amatuximab and novel agents targeting mesothelin for solid tumors

Mesothelin (MSLN) is considered a promising target for cancer therapy. Originally extracted in 1992 after the immunization of mice with a human ovarian cancer (OC) cell line and cloned in 1996, MSLN seems to be involved in cell adhesion and metastasis. MSLN is prevalent in mesothelia tissues but is expressed in several human cancers, such as OC, pancreatic cancer, mesothelioma, and lung cancer. Amatuximab (MORAb-009) is a mouse-human chimeric monoclonal antibody with a selective affinity for MSLN. The principal mechanism of action comprises inhibition of binding of MSLN with the antigen CA125/MUC16. The highest phase of development is actually a Phase II trial (MORAb-009-201, Europe). In this review, we describe the mechanism of action of amatuximab and other MSLN-targeting novel drugs, along with a discussion about the expected efficacy, safety, and toxicity of this promising group of agents and implications for future research and clinical practice.

The Third Italian Consensus Conference for Malignant Pleural Mesothelioma: State of the art and recommendations

Malignant Pleural Mesothelioma (MPM) remains a relevant public health issue, and asbestos exposure is the most relevant risk factor. The incidence has considerably and constantly increased over the past two decades in the industrialized countries and is expected to peak in 2020-2025. In Italy, a standardized-rate incidence in 2011 among men was 3.5 and 1.25 per 100,000 in men and women, respectively, and wide differences are noted among different geographic areas. The disease remains challenging in terms of diagnosis, staging and treatment and an optimal strategy has not yet been clearly defined. The Third Italian Multidisciplinary Consensus Conference on Malignant Pleural Mesothelioma was held in Bari (Italy) in January 30-31, 2015. This Consensus has provided updated recommendations on the MPM management for health institutions, clinicians and patients.

Mesothelioma from asbestos exposures: Epidemiologic patterns and impact in the United States

Mesothelioma, a rare tumor, is highly correlated with asbestos exposure. Mesothelioma, similar to all asbestos-related diseases, is dose/intensity dependent to some degree, and studies showed the risk of mesothelioma rises with cumulative exposures. Multiple processes occur in an individual before mesothelioma occurs. The impact of mesothelioma in the United States has been continuous over the last half century, claiming between 2,000 and 3,000 lives each year. Mesothelioma is a preventable tumor that is more frequently reported as associated with asbestos exposure among men than women. However, the rate of asbestos-associated mesothelioma is on the rise among women due to better investigation into their histories of asbestos exposure. It is of interest that investigators detected asbestos-associated cases of mesothelioma in women from nonoccupational sources-that is, bystander, incidental, or take-home exposures. It is postulated that asbestos-associated mesotheliomas, in both men and women, are likely underreported. However, with the implementation of the most recent ICD-10 coding system, the correlation of mesothelioma with asbestos exposure is expected to rise to approximately 80% in the United States. This study examined the demographic and etiological nature of asbestos-related mesothelioma.

An asbestos-exposed family with multiple cases of pleural malignant mesothelioma without inheritance of a predisposing BAP1 mutation

We report a family with domestic exposure to asbestos and diagnosis of multiple cancers, including eight pleural malignant mesotheliomas and several other lung or pleural tumors. DNA sequence analysis revealed no evidence for an inherited mutation of BAP1. Sequence analysis of other potentially relevant genes, including TP53, CDKN2A, and BARD1, also revealed no mutation. DNA microarray analysis of tissue from two mesotheliomas revealed multiple genomic imbalances, including consistent losses of overlapping segments in 2q, 6q, 9p, 14q, 15q, and 22q, but no losses of chromosome 3 harboring the BAP1 locus. However, the results of immunohistochemical analysis demonstrated loss of nuclear BAP1 staining in three of six mesotheliomas tested, suggesting that somatic alterations of BAP1 occurred in a subset of tumors from this family. Since mesothelioma could be confirmed in only a single generation, domestic exposure to asbestos may be the predominant cause of mesothelioma in this family. Given the existence of unspecified malignant pleural tumors and lung cancers in a prior generation, we discuss the possibility that some other tumor susceptibility or modifier gene(s) may contribute to the high incidence of mesothelioma in this family. Because the incidence of mesothelioma in this family is higher than that expected even in workers heavily exposed to asbestos, we conclude that both asbestos exposure and genetic factors have played a role in the high rate of mesothelioma and potentially other pleural or lung cancers seen in this family. 

Absence of germline mutations in BAP1 in sporadic cases of malignant mesothelioma

Malignant mesothelioma (MM) is a uniformly fatal tumour caused predominantly by exposure to asbestos. It is not known why some exposed individuals get mesothelioma and others do not. There is some epidemiological evidence of host susceptibility. BAP1 gene somatic mutations and allelic loss are common in mesothelioma and recently a BAP1 cancer syndrome was described in which affected individuals and families had an increased risk of cancer of multiple types, including MM. To determine if BAP1 mutations could underlie any of the sporadic mesothelioma cases in our cohort of patients, we performed targeted deep sequencing of the BAP1 exome on the IonTorrent Proton sequencer in 115 unrelated MM cases. No exonic germline BAP1 mutations of known functional significance were observed, further supporting the notion that sporadic germline BAP1 mutations are not relevant to the genetic susceptibility of MM.

Mesothelioma in Mongolia: case report

BACKGROUND

More than 80% of cases of mesothelioma worldwide have a history of asbestos exposure. In Mongolia, workers in coal burning thermal power plants (TPP) have widely utilized asbestos as an insulation material.

METHODS

We describe the case of a 47-year-old woman diagnosed with a malignant pleural mesothelioma. She worked in a TPP in Ulaanbaatar, Mongolia for 28 years.

RESULTS

A computer tomography (CT) scan showed a circumferential ring around her left lung, and tissues' samples had a biphasic variant of mesothelioma with epithelioid and sarcomatoid components.

DISCUSSION

This is the first reported case of mesothelioma in Mongolia. We expect additional cases of mesothelioma, as well as other asbestos related diseases, will be identified in the future. In order to properly track asbestos related diseases in the country, we recommend the creation of an asbestos related disease registry.

Impact of an asbestos cement factory on mesothelioma incidence: global assessment of effects of occupational, familial, and environmental exposure

Few studies have examined the incidence of malignant mesothelioma (MM) associated with distinct sources of asbestos exposure (occupational, familial, or environmental). We assessed the impact of asbestos exposure-global and by source-on the incidence of MM in Broni, an Italian town in which an asbestos cement factory once operated (1932-1993). Based on data collected by the Lombardy Mesothelioma Registry, we calculated the number of observed and expected MM cases among workers, their cohabitants, and people living in the area in 2000-2011. We identified 147 MM cases (17.45 expected), 138 pleural and nine peritoneal, attributable to exposure to asbestos from the factory. Thirty-eight cases had past occupational exposure at the factory (2.33 expected), numbering 32 men (26 pleural, six peritoneal) and six women (four pleural, two peritoneal). In the families of the workers, there were 37 MM cases (4.23 expected), numbering five men (all pleural) and 32 women (31 pleural, one peritoneal). Among residents in Broni or in the adjacent/surrounding towns, there were 72 cases of pleural MM (10.89 expected), numbering 23 men and 49 women. The largest MM excess was found in the towns of Broni (48 observed, 3.68 expected) and Stradella (16 observed, 1.85 expected). This study documents the large impact of the asbestos cement factory, with about 130 excess MM cases in a 12-year period. The largest MM burden was among women, from non-occupational exposure. Almost half of the MM cases were attributable to environmental exposure.