Malignant pleural mesothelioma: an update on investigation, diagnosis and treatment

Trimodality therapy of malignant pleural mesothelioma with helical tomotherapy

OBJECTIVE

The purpose of this study was to determine the efficacy and tolerability of hemithoracic radiotherapy implemented with helical tomotherapy (HTT) in malignant pleural mesothelioma (MPM) patients.

METHODS

Between October 2018 and December 2020, data from 11 MPM patients who received trimodality therapy, including lung-sparing surgery (pleurectomy-decortication, P/D), adjuvant chemotherapy (cisplatin+ pemetrexed), and radiotherapy, were retrospectively reviewed. HTT was used to deliver a total of 30 Gy, 50-54 Gy or 59.4-60 Gy to R2 disease with 1.8-2 Gy daily doses. Descriptive data are presented in number (percentage) or median (minimum- maximum). The Kaplan-Meier method was used to calculate survival data. In patients with toxicities, the risk organ doses were compared using the Mann-Whitney U test.

RESULTS

The median follow-up was 20.5 (12-30) months. Two-year local control, disease-free, and overall survival rates were 48.5%, 49%, and 77.9%, respectively. The median prescribed dose for planning target volume (PTV) was 50.4±8.7 (30-60) Gy. Mean dose (D_mean) of total lung was 19.9±6 (10.4-26) Gy; the V20 (%) of ipsilateral and contralateral lungs were 89.±11.2 (62.7-100) and 0.7±2.1 (0.49-5.9), respectively. Esophageal D_mean and maximum doses (D_max) were found as 21.7±8.4 (7.4-34) and 53.1±10.4 (25.4-64.4) Gy, respectively. V30 (%) and Dmean of heart were 22.3%±13.4% (3.9-47) and 21±5.7 (10.8-29.3) Gy, respectively. D_max of medulla spinalis (MS) was 38.6± 1.3 (13.7-48) Gy. Grade 1-2 radiation pneumonitis (RP) developed in 4 (36.4%) and esophagitis in 2 (18.2%) patients. RP was found to be associated with MS and esophageal doses (p<0.05). Myelitis was diagnosed in 1 (9.1%) patient (MS D_max: 29 Gy).

CONCLUSION

HTT can be used as part of trimodality therapy for MPM patients with acceptable toxicities. MS and esophageal doses should be considered for radiation pneumonitis risk, and new dose constraints for these organs should be defined.

Geldanamycin treatment does not result in anti-cancer activity in a preclinical model of orthotopic mesothelioma

Mesothelioma is characterised by its aggressive invasive behaviour, affecting the surrounding tissues of the pleura or peritoneum. We compared an invasive pleural model with a non-invasive subcutaneous model of mesothelioma and performed transcriptomic analyses on the tumour samples. Invasive pleural tumours were characterised by a transcriptomic signature enriched for genes associated with MEF2C and MYOCD signaling, muscle differentiation and myogenesis. Further analysis using the CMap and LINCS databases identified geldanamycin as a potential antagonist of this signature, so we evaluated its potential in vitro and in vivo. Nanomolar concentrations of geldanamycin significantly reduced cell growth, invasion, and migration in vitro. However, administration of geldanamycin in vivo did not result in significant anti-cancer activity. Our findings show that myogenesis and muscle differentiation pathways are upregulated in pleural mesothelioma which may be related to the invasive behaviour. However, geldanamycin as a single agent does not appear to be a viable treatment for mesothelioma.

Pleural Mesothelioma: A Rapid Evolution of an Indolent Disease

Mesothelioma is a rare and insidious neoplasm and is characterized by its highly malignant and aggressive nature. The most common etiology is asbestos exposure, but there are some reports without known asbestos exposure and other factors leading to malignant pleural mesothelioma (MPM). Here, we present the case of a 58-year-old woman with pleuritic chest pain, dyspnea, and fever on presentation to the emergency department (ED), which caused several admissions to the ED in 20 days. The patient was then admitted to the internal medicine department with a diagnosis of community-acquired pneumonia with parapneumonic effusion. During hospitalization, a positron emission tomography (PET) scan, thoracic computed tomography (CT), and pleural biopsy were performed and a final diagnosis of malignant epithelioid pleural mesothelioma was made. Six weeks after the onset of symptoms, the patient presented with an exponential disease progression, dying two months after the diagnosis, despite the initiation of chemotherapy. MPM remains a diagnostic and therapeutic challenge with a very poor prognosis. However, studies show that mesothelioma patients who undergo treatment live at least twice as long as patients who do not receive treatment. This case report is particularly significant because, although it was epithelioid mesothelioma, multiple solid masses were noted on CT and the patient exhibited rapid disease progression, dying a few weeks after starting treatment.

Longitudinal monitoring of response to chemotherapy in patients with malignant pleural mesothelioma by biomarkers

BACKGROUND

The aim of the study was to longitudinally investigate the serum levels of mesothelin, sestrin1, hyaluronan synthase 2 (HAS2), midkine, and high mobility group box 1 (HMGB1) before and after chemotherapy and at the time of relapse in malignant pleural mesothelioma (MPM) patients treated with chemotherapy and to compare the changes in biomarker levels with radiological treatment outcome.

METHODS

A total of 64 MPM patients treated with chemotherapy were enrolled in the study and longitudinally followed for changes in biomarker levels in response to treatment. Biomarkers levels were measured in serum using a human ELISA kit. Relative and absolute changes in biomarker levels were compared with the best radiological overall response at each time point.

RESULTS

Median survival was 20.0 ± 2.4 (15.3-24.7) months in patients with partial and complete response, 17.0 ± 1.0 (15.0-19.0) months in patients with stable disease, and 9.0 ± 1.0 (7.0-11.0) months in patients with progressive disease. A significant decrease in serum levels of mesothelin, midkine, and HMGB1 was observed in patients with radiologically partial and complete responses to chemotherapy (p< 0.001, p= 0.016, and p= 0.039, respectively). In these patients, mesothelin levels decreased by 15%, midkine levels by 7%, and HMGB1 levels by 15%. In addition, HMGB1 serum levels were found to significantly increase by 15% in patients with radiologically progressive responses to chemotherapy compared to pretreatment serum levels (p= 0.035). In patients with partial and complete response to chemotherapy, mesothelin levels increased by 15%, midkine by 12%, and sestrin1 by 8% when the disease recurred (p= 0.004, p= 0.004 and p= 0.044, respectively).

CONCLUSION

Biomarkers may be useful in the longitudinal monitoring of response to treatment in MPM. However, the results of our study should be validated in larger groups with sufficient case numbers from multicenter institutions.

Carbon-ion beam irradiation in combination with cisplatin effectively suppresses xenografted malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rare aggressive cancer. This study investigated the growth-inhibitory effects of the combination of carbon ion beam irradiation (IR) and cisplatin (CDDP) on MPM xenografts. Carbon-ion beam IR at 15 Gy effectively inhibited tumor growth and decreased the tumor volume more than 90% after 9 weeks. However, tumor regrowth was observed after 17 weeks. The combination of carbon-ion beam IR (15 Gy) and CDDP significantly suppressed tumor growth after 9 weeks, with tumor regression being observed for more than 18 weeks. In contrast, X-ray IR (30 Gy) alone or in combination with CDDP effectively suppressed tumor growth and decreased the tumor volume after 11 weeks, but tumor growth was observed after 15 weeks. Carbon-ion beam IR at 25 Gy resulted in complete tumor regression without tumor regrowth in the 20-week follow-up period. Histopathological analysis revealed that combination of carbon-ion beam IR and CDDP exerted effective cytotoxic effects on MPM xenograft tumor cells and significantly promoted tumor cell necrosis, cavitation, and fibrosis when compared with individual treatment with carbon-ion beam, X-ray IR, or CDDP. Immunohistochemical analysis revealed that the expression levels of tumor cell migration and invasion-related proteins such as CXCL12, MMP2 and MMP9 were not significantly affected upon low dose (15 Gy) carbon-ion beam IR alone or in combination with CDDP but were markedly upregulated upon treatment with CDDP alone relative to control. However, IR with a high dose (25 Gy) carbon-ion beam inhibited tumor growth without upregulating these proteins. In conclusion, the combination of IR with a low dose (15 Gy) carbon ion beam and CDDP effectively suppressed MPM tumor in vivo without significantly upregulating CXCL12, MMP2 and MMP9, suggesting that combination therapy of carbon ion beam IR and chemotherapy is a promising therapeutic strategy for MPM.

Diagnosis of malignant pleural disease: Ultrasound as "a detective probe"

BACKGROUND

Malignant pleural mesothelioma (MPM) is an invasive, aggressive pleural tumor with a predominantly local spread. The objective of this study was to assess thoracic ultrasound (TUS) as an imaging modality with high sensitivity for the identification of malignant pleural involvement and in order to guide pleural biopsies.

METHODS

In this retrospective single-center study between January 2018 and June 2022, 51 consecutive patients with impassable circumferential pleural thickening underwent TUS at the Thoracic Surgery Unit of the Vanvitelli University of Naples. Pleural biopsies were performed, and then large and multiple samples were sent to the pathological anatomy for histological examination.

RESULTS

In all patients who underwent ultrasound examination, we chose the optimal point of entry to perform pleural biopsies and selected the areas of greater thickening without pleural effusion. No patient had any complications. No drainage tubes were placed after the pleural biopsies and no pneumothorax was present during the following days of hospitalization. The patients were discharged on the second postoperative day.

CONCLUSION

With TUS the precise pleural thickening localization, local infiltration, mass extent, its nature (solid, cystic or complex) and ultrasound features can be easily defined. Furthermore, ultrasound is more economical than computed tomography and avoids the risks associated with radiation. Thoracic ultrasound is an important component of the diagnostic procedure in detecting a safe entry site for biopsies of MPMs.

Near Missed Case of Occupational Pleural Malignant Mesothelioma, a Case Report and Latest Therapeutic Options

Asbestos use started to be gradually banned in Europe from 1991 onwards, and there are currently strict occupational exposure limits for asbestos. However, malignant mesothelioma has a long latency time (in some cases up to 50-60 years), so the risks related to asbestos exposure should not be forgotten. Considering the increased risk of lung cancer following the inhalation of asbestos fibers, lifetime health monitoring should be considered in people occupationally exposed to asbestos, with an emphasis on the respiratory system. An assessment of their occupational history should be performed rigorously, especially in the areas with a history of asbestos production/use, as this is a key element for an early diagnosis and appropriate treatment. This case report presents a near-missed case of occupational pleural malignant mesothelioma. The latency time between the first asbestos exposure and the diagnosis of occupational pleural malignant mesothelioma was 49 years. The accurate diagnosis was made two years after the first symptoms appeared.

Protocol for a prospective observational cohort study collecting data on demographics, symptoms and biomarkers in people with mesothelioma (ASSESS-meso)

INTRODUCTION

Mesothelioma is a heterogeneous disease that can be challenging to monitor and prognosticate. ASSESS-meso is a multicentre, prospective, longitudinal observational cohort study of patients with mesothelioma. The primary aim is to describe different clinical phenotypes and investigate predictive and prognostic factors, including biomarkers from blood and pleural fluid. The secondary aim is to provide a resource for future trials and substudies.

METHODS AND ANALYSIS

We aim to recruit 700 patients with a histological, cytological or clinicopathological diagnosis of mesothelioma, at any anatomical site (pleural, peritoneal, pericardial, etc). Longitudinal data will be collected, including clinical information, radiological investigations, blood tests and patient-reported outcome measures for breathlessness, chest pain and sweats. Preplanned analyses will use Cox proportional hazards method to evaluate factors associated with survival, linear and logistic regression models to investigate associations with symptoms, and analysis of variance modelling to explore changes in symptoms over time.

ETHICS AND DISSEMINATION

Ethical approval has been granted by the Research Ethics Committee South West-Central Bristol (17-SW-0019) and Health Research Authority (IRAS ID 220360). A study steering committee has been established and results will be published OpenAccess in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ISRCTN: 61861764.

Examining the impact of physical function performance in predicting patient outcomes after lung-sparing surgery for malignant pleural mesothelioma

PURPOSE

The purpose of this study was to examine the impact of physical function performance and pulmonary function on patient outcomes after lung-sparing surgery for malignant pleural mesothelioma (MPM).

MATERIALS AND METHODS

A retrospective review of 54 patients with MPM from 2015 to 2020 was performed. The primary objective was to assess whether physical function, as measured by the Eastern Cooperative Oncology Group Performance Status (ECOG), and pulmonary function tests were predictive of postoperative patient outcomes (ventilator days, chest tube days, hospital length of stay). A secondary objective was to explore demographic and preoperative variables that best predict postoperative physical function and patient outcomes.

RESULTS

Data include 54 patients who underwent extended pleurectomy-decortication. Preoperative ECOG was a significant predictor of postoperative patient outcomes while preoperative lung function lacked predictive ability. Preoperative ECOG was also predictive of preoperative lung function. Age on the day of surgery was the best predictor of postoperative physical function, which was significantly reduced postoperatively.

CONCLUSIONS

Preoperative physical function performance was a significant predictor of postoperative outcomes. The results of our study highlight the importance of physical function in patients with MPM and support the need for early rehabilitation and further research to determine optimal rehabilitation interventions.IMPLICATIONS FOR REHABILITATIONPreoperative physical function can predict outcomes after lung-sparing surgery for malignant pleural mesothelioma (MPM).Physical function in patients with MPM should be carefully examined.To accurately reflect patients' abilities, patient assessment should include both patient-reported outcomes and performance-based measures.Patients with MPM should receive rehabilitation early after diagnosis and throughout the continuum of care.

A combination of intrinsic and extrinsic features improves prognostic prediction in malignant pleural mesothelioma

BACKGROUND

Malignant pleural mesothelioma (MPM) is a lung pleural cancer with very poor disease outcome. With limited curative MPM treatment available, it is vital to study prognostic biomarkers to categorise different patient risk groups.

METHODS

We defined gene signatures to separately characterise intrinsic and extrinsic features, and investigated their interactions in MPM tumour samples. Specifically, we calculated gene signature scores to capture the downstream pathways of major mutated driver genes (BAP1, NF2, SETD2 and TP53) as tumour-intrinsic features. Similarly, we inferred the infiltration levels for major immune cells in the tumour microenvironment to characterise tumour-extrinsic features. Lastly, we integrated these features with clinical factors to predict prognosis in MPM.

RESULTS

The gene signature scores were more prognostic than the corresponding genomic mutations, mRNA and protein expression. High immune infiltration levels were associated with prolonged survival. The integrative model indicated that tumour features provided independent prognostic values than clinical factors and were complementary with each other in survival prediction.

CONCLUSIONS

By using an integrative model that combines intrinsic and extrinsic features, we can more correctly predict the clinical outcomes of patients with MPM.

Marital status as an independent prognostic factor for patients of malignant pleural mesothelioma

Objectives

The prognostic impact of marital status on malignant pleural mesothelioma (MPM) is not investigated. This paper probes into the relationship between the prognosis of MPM and marital status.

Materials and methods

The Surveillance, Epidemiology, and End Results (SEER) database of American had been applied to choose eligible patients over the 2004–2015 periods. Moreover, cancer-specific survival (CSS) and overall survival (OS) of unmarried and married groups were compared.

Results

A total of 3,997 patients in total had been identified, including 2,735 (68.43%) married patients. In comparison to unmarried patients, married ones tended to be younger, male, white, and received active treatment (surgery, chemotherapy, or radiotherapy). In addition, the 1, 3, and 5-year CSS rates were 44.40, 12.09, and 6.88% in married patients, while 35.75, 12.12, and 6.37% in unmarried group (p = 0.0014). At the same time, the 1, 3, and 5-year OS rates were 41.84, 10.56, and 5.91% in married patients, while 33.67, 10.44, and 4.93%, respectively, in the unmarried group (p < 0.0001). As revealed by the multivariate analysis results, the marital status was an independent favorable prognostic factor, in which the married groups showed better CSS [hazard ratio (HR): 0.870; 95% confidence interval (CI): 0.808–0.938; p < 0.001] as well as OS (HR: 0.871; 95% CI: 0.810–0.936; p < 0.001). According to the results of subgroup analysis, the CSS and OS survival of married groups were better than the unmarried groups in almost all the subgroups.

Conclusion

Marital status is an independent favorable prognostic indicator of MPM. Poor prognosis in unmarried patients is likely to be related to insufficient treatments and socioeconomic and psychosocial factors.

Establishment of predictive nomogram and web-based survival risk calculator for malignant pleural mesothelioma: A SEER database analysis

Background

Malignant pleural mesothelioma (MPM) is an uncommon condition with limited available therapies and dismal prognoses. The purpose of this work was to create a multivariate clinical prognostic nomogram and a web-based survival risk calculator to forecast patients’ prognoses.

Methods

Using a randomization process, training and validation groups were created for a retrospective cohort study that examined the Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2015 for individuals diagnosed with MPM (7:3 ratio). Overall survival (OS) and cancer-specific survival (CSS) were the primary endpoints. Clinical traits linked to OS and CSS were identified using Least Absolute Shrinkage and Selection Operator (LASSO) Cox regression analysis, which was also utilized to develop nomogram survival models and online survival risk calculators. By charting the receiver operating characteristic (ROC), consistency index (C-index), calibration curve, and decision curve analysis (DCA), the model’s performance was assessed. The nomogram was used to classify patients into various risk categories, and the Kaplan-Meier method was used to examine each risk group’s survival rate.

Results

The prognostic model comprised a total of 1978 patients. For the total group, the median OS and CSS were 10 (9.4-10.5) and 11 (9.4-12.6) months, respectively. As independent factors for OS and CSS, age, gender, insurance, histology, T stage, M stage, surgery, and chemotherapy were chosen. The calibration graphs demonstrated good concordance. In the training and validation groups, the C-indices for OS and CSS were 0.729, 0.717, 0.711, and 0.721, respectively. Our nomogram produced a greater clinical net benefit than the AJCC 7th edition, according to DCA and ROC analysis. According to the cut-off values of 171 for OS and 189 for CSS of the total scores from our nomogram, patients were classified into two risk groups. The P-value &lt; 0.001 on the Kaplan-Meier plot revealed a significant difference in survival between the two patient groups.

Conclusions

Patient survival in MPM was correctly predicted by the risk evaluation model. This will support clinicians in the practice of individualized medicine.

Diagnostic ability and its influenced factors of ultrasound-guided percutaneous pleural needle biopsy diagnosis for malignant pleural mesothelioma

Background

Malignant pleural mesothelioma (MPM) is a highly invasive malignant tumor. Ultrasound guidance has the advantages of real-time, convenience and nonradiative. We sought to identify diagnostic value and its influenced factors of ultrasound-guided percutaneous pleural needle biopsy (US-PPNB) for MPM.

Methods

Patients who underwent US-PPNB between March 2014 and March 2020 and were finally diagnosed with MPM were retrospectively analyzed. We retrospectively analyzed the US-PPNBs pathological results of all patients clinically confirmed as MPM, and divided US-PPNBs into correctly and incorrectly diagnosed groups. Patient, thoracic, and biopsy variables that affected diagnostic accuracy were assessed. All variables significant on univariate analyses were subjected to multivariate logistic regression to identify significant predictors of diagnostic accuracy. We derived cutoffs for all significant continuous variables and used the Mantel–Haenszel test to determine whether the diagnostic accuracy of US-PPNB for MPM increased with pleural thickness.

Results

In total, 49 patients with clinically confirmed MPM underwent US-PPNB; 37 diagnoses were correct and 12 were incorrect (accuracy = 75.5%). The pleura was significantly thicker in the correctly diagnosed group (p < 0.001). The pleural thickness cutoff was 4.15 mm and diagnostic accuracy increased with pleural thickness grade (p for trend <0.05). The diagnostic accuracy was significantly higher when 16-G rather than 18-G biopsy needles were used (p < 0.05). Multivariate logistic regression showed that pleural thickness (odds ratio: 17.2, 95% confidence interval: 2.8–104.1, p = 0.002) and needle size (odds ratio: 6.8, 95% confidence interval: 1.0–44.5, p = 0.044) independently predicted diagnostic accuracy.

Conclusion

US-PPNB afforded high MPM diagnostic accuracy, and pleural thickness and needle size significantly impacted accuracy.

Global magnitude and temporal trend of mesothelioma burden along with the contribution of occupational asbestos exposure in 204 countries and territories from 1990 to 2019: Results from the Global Burden of Disease Study 2019

Understanding the burden of mesothelioma with the contribution of occupational asbestos exposure globally provides essential foundations for cancer control, policy decisions and resource allocation. Globally, 34,511 incident cases, 29,251 deaths and 668,104 disability-adjusted life years (DALYs) of mesothelioma were estimated in 2019. The age-standardized rates of incidence, mortality and DALYs all showed a slightly declining trend over the past 30 years, but the latest absolute number of mesothelioma burden almost doubled since 1990. The burden rate decreased among the population aged under 70 years, but increased among the population aged over 80 years, especially in the High socio-demographic index (SDI) region. The burden rate of mesothelioma attributable to asbestos exposure was positively associated with SDI at the national level. This study depicted a continuous increase in mesothelioma burden globally over the past 30 years. Controlling occupational asbestos exposure will reduce the mesothelioma burden, especially for higher SDI regions.

A detection panel of novel methylated DNA markers for malignant pleural effusion

Background

Cytology remains the gold standard for the detection of malignant cells in pleural effusion. However, its sensitivity is limited. The aim of this study was to establish a novel panel of cancer-specific methylated genes for the differential diagnosis of malignant pleural effusion (MPE).

Methods

A cohort of 100 cancer patients (68 lung cancer, 32 other malignant tumors) and 48 patients with benign disease presenting with pleural effusion was prospectively enrolled. Pleural effusion was evaluated by means of cytopathological investigation and DNA methylation of SHOX2, RASSF1A, SEPTIN9 and HOXA9 in the cellular fraction. DNA methylation in bisulfite-converted DNA was determined using quantitative methylation-specific real-time PCR (MS-PCR). Cytopathological and DNA methylation results were evaluated with regard to the final clinical diagnosis.

Results

The LungMe® SHOX2 and RASSF1A Assay (Tellgen Corporation, China) has been reported to be highly sensitive and specific for lung cancer using bronchial aspirates. As expected, LungMe® detected metastases of lung cancer (sensitivity: 76.5%) as well as metastases of other malignant tumors (sensitivity: 68.8%). OncoMe, a novel combination of SHOX2, RASSF1A, SEPTIN9 and HOXA9 methylation, led to an additional 11% increase in the detection rate of MPE, resulting in a sensitivity of 85% and a specificity of 96%. Overall, OncoMe showed a higher positive detection rate in SCLC (100%), LUAC (87%), OC (100%), BC (92.9%), GC (80.0%), and MESO (80%) than in LUSC (50%). Cytopathological analyses only detected 23 positive samples, which were all positively measured by both LungMe® and OncoMe.

Conclusion

OncoMe has potential for use as a biomarker for the detection of MPE, even not limited to lung cancer.

KRAS Pathway Alterations in Malignant Pleural Mesothelioma: An Underestimated Player

Simple Summary

Malignant pleural mesothelioma (MPM) is a rare, incurable cancer. KRAS pathway alterations are frequent in human MPM but have been likely underestimated by next generation sequencing studies.

Abstract

Malignant pleural mesothelioma (MPM) is a rare, incurable cancer of the mesothelial cells lining the lungs and the chest wall that is mainly caused by asbestos inhalation. The molecular mechanisms of mesothelial carcinogenesis are still unclear despite comprehensive studies of the mutational landscape of MPM, and the most frequently mutated genes BAP1, NF2, CDKN2A, TP53, and TSC1 cannot cause MPM in mice in a standalone fashion. Although KRAS pathway alterations were sporadically detected in older studies employing targeted sequencing, they have been largely undetected by next generation sequencing. We recently identified KRAS mutations and copy number alterations in a significant proportion of MPM patients. Here, we review and analyze multiple human datasets and the published literature to show that, in addition to KRAS, multiple other genes of the KRAS pathway are perturbed in a significant proportion of patients with MPM.

ER Stress Response and Induction of Apoptosis in Malignant Pleural Mesothelioma: The Achilles Heel Targeted by the Anticancer Ruthenium Drug BOLD-100

Simple Summary

Malignant mesothelioma is a rare cancer arising from the serosal surfaces of the body, mainly from the pleural layer. This cancer, strongly linked to asbestos exposure, shows a very inauspicious prognosis. In fact, there is no efficient therapeutic treatment for malignant pleural mesothelioma (MPM). Thus, there is an urgent need to develop novel therapeutic approaches to treat this form of cancer. Our previous study showed the importance of GRP78 in MPM survival. BOLD-100 is a specific modulator of GRP78 and we have observed that it shows cytotoxicity against MPM cells. In particular, we describe that BOLD-100 increases oxidative stress and deregulates the calcium homeostasis leading to cell stress and, ultimately, to cell death. Our in vitro data strongly suggest that BOLD-100 inhibits the growth of MPM cell lines, proposing the application as a single agent, or in combination with other standard-of-care drugs, to treat MPM.

Abstract

Malignant mesothelioma is a rare cancer arising from the serosal surfaces of the body, mainly from the pleural layer. This cancer is strongly related to asbestos exposure and shows a very inauspicious prognosis, because there are scarce therapeutic options for this rare disease. Thus, there is an urgent need to develop novel therapeutic approaches to treat this form of cancer. To explore the biology of malignant pleural mesothelioma (MPM), we previously observed that MPM cell lines show high expression of the GRP78 protein, which is a chaperone protein and the master regulator of the unfolded protein response (UPR) that resides in the endoplasmic reticulum (ER). Based on our previous studies showing the importance of GRP78 in MPM, we observed that BOLD-100, a specific modulator of GRP78 and the UPR, shows cytotoxicity against MPM cells. Our studies demonstrated that BOLD-100 increases ROS production and Ca²⁺ release from the ER, leading to ER stress activation and, ultimately, to cell death. Our in vitro data strongly suggest that BOLD-100 inhibits the growth of MPM cell lines, proposing the application as a single agent, or in combination with other standard-of-care drugs, to treat MPM.

Repurposing clofazimine for malignant pleural mesothelioma treatment - In-vitro assessment of efficacy and mechanism of action

AIMS

Malignant pleural mesothelioma (MPM) is a rare cancer of lungs' pleural cavity, with minimally effective therapies available. Thus, there exists a necessity for drug repurposing which is an attractive strategy for drug development in MPM. Repurposing of an old FDA-approved anti-leprotic drug, Clofazimine (CFZ), presents an outstanding opportunity to explore its efficacy in treating MPM.

MAIN METHODS

Cytotoxicity, scratch assay, and clonogenic assays were employed to determine CFZ's ability to inhibit cell viability, cell migration, and colony growth. 3D Spheroid cell culture studies were performed to identify tumor growth inhibition potential of CFZ in MSTO-211H cell line. Gene expression analysis was performed using RT-qPCR assays to determine the CFZ's effect of key genes. Western blot studies were performed to determine CFZ's ability to induce apoptosis its effect to induce autophagy marker.

KEY FINDINGS

CFZ showed significant cytotoxicity against both immortalized and primary patient-derived cell lines with IC₅₀ values ranging from 3.4 μM (MSTO-211H) to 7.1 μM (HAY). CFZ significantly impaired MPM cell cloning efficiency, migration, and tumor spheroid formation. 3D Spheroid model showed that CFZ resulted in reduction in spheroid volume. RT-qPCR data showed downregulation of genes β-catenin, BCL-9, and PRDX1; and upregulation of apoptosis markers such as PARP, Cleaved caspase 3, and AXIN2. Additionally, immunoblot analysis showed that CFZ down-regulates the expression of β-catenin (apoptosis induction) and up-regulates p62, LC3B protein II (autophagy inhibition).

SIGNIFICANCE

It can be concluded that CFZ could be a promising molecule to repurpose for MPM treatment which needs numerous efforts from further studies.

A case report of IgG4-related respiratory disease with pleural effusion and a literature review

RATIONALE

IgG4-related respiratory disease (IgG4-RRD) is a chronic autoimmune disease that affects the respiratory system and organs outside the respiratory system. This study explored the diagnosis and treatment of a case of IgG4-RRD with unilateral pleural effusion diagnosed using medical thoracoscopy, and provides an associated literature review. This report summarizes the clinical characteristics of IgG4-RRD involving the pleura to improve the diagnosis of this disease.

PATIENT CONCERNS

A 39-year-old man presented with a 2-week history of cough and chest tightness. Both physical examination and imaging supported the presence of left pleural effusion.

DIAGNOSIS

Medical electronic thoracoscopy was performed to obtain a pleural biopsy, which showed lymphoplasmacytic infiltration, 40 IgG4+ plasma cells per High Power Field (HPF) on microscopy, IgG4/IgG ratio >50%, phlebitis obliterans, and storiform fibrosis. The final diagnosis was IgG4-RRD.

INTERVENTIONS AND OUTCOMES

The patient was treated with methylprednisolone, after which his symptoms improved, and he was discharged. Oral hormone therapy was continued outside the hospital. After 4 months, the patient returned to the hospital and his condition had improved significantly.

LESSONS

Pleural involvement in IgG4-RRD is rare, and its diagnosis depends on pleural biopsy. Thoracoscopy usually reveals pleural thickening, pleural nodules, and milky white plaques.

Near-Infrared Photoimmunotherapy for Thoracic Cancers: A Translational Perspective

The conventional treatment of thoracic tumors includes surgery, anticancer drugs, radiation, and cancer immunotherapy. Light therapy for thoracic tumors has long been used as an alternative; conventional light therapy also called photodynamic therapy (PDT) has been used mainly for early-stage lung cancer. Recently, near-infrared photoimmunotherapy (NIR-PIT), which is a completely different concept from conventional PDT, has been developed and approved in Japan for the treatment of recurrent and previously treated head and neck cancer because of its specificity and effectiveness. NIR-PIT can apply to any target by changing to different antigens. In recent years, it has become clear that various specific and promising targets are highly expressed in thoracic tumors. In combination with these various specific targets, NIR-PIT is expected to be an ideal therapeutic approach for thoracic tumors. Additionally, techniques are being developed to further develop NIR-PIT for clinical practice. In this review, NIR-PIT is introduced, and its potential therapeutic applications for thoracic cancers are described.

Understanding clinical decision-making in mesothelioma care: a mixed methods study

INTRODUCTION

Malignant pleural mesothelioma is a rare, incurable cancer arising from previous asbestos exposure; patients have a poor prognosis, with a median survival rate of 8-14 months. Variation in mesothelioma clinical decision-making remains common with a lack of multidisciplinary knowledge sharing, leading to inconsistencies in treatment decisions. The study aimed to explore which factors impacted on clinicians' decision-making in mesothelioma care, with a view to optimising the mesothelioma care pathway.

METHODS

This mixed methods study consisted of documentary analysis of local and national guidelines, policies or documents pertaining to mesothelioma care pathways, secondary analysis of mesothelioma patient data, and interviews with clinicians attending lung cancer and/or mesothelioma-specific multidisciplinary team meetings. The study took place at three National Health Service trusts in England. Documentations relating to patients' treatment pathways were collated and reviewed qualitatively. Records of patients with mesothelioma were extracted from hospital patient records and data collected on diagnosis date, treatment, mortality rates, survival postdiagnosis, age and clinical care team. Data were statistically analysed. Interviews with clinicians explored influences on clinical decision-making, including challenges or barriers involved. Data were thematically analysed. The Strengthening the Reporting of Observational Studies in Epidemiology reporting checklist was used.

RESULTS

There were differences in the structure and delivery of mesothelioma treatment and care between trusts. Four main themes were identified: 'collaboration and communication', 'evidence base and knowledge', 'role of the clinician' and 'role of the patient'. Two cross-cutting themes relating to the role of the mesothelioma nurse specialist and the impact of COVID-19 were identified.

DISCUSSION

There is a need to review the structure of mesothelioma multidisciplinary team meetings to ensure patients are reviewed by clinicians with appropriate knowledge, expertise and understanding of how, why and when decisions should be made. There is a need for expert clinicians in mesothelioma care to promote an up-to-date evidence and knowledge base within the wider multidisciplinary team.

Malignant pleural mesothelioma: treatment patterns and humanistic burden of disease in Europe

Background

Malignant pleural mesothelioma (MPM) is an aggressive and rare tumour with poor prognosis. Most patients are diagnosed with advanced disease and there is a paucity of data on the humanistic burden of MPM in terms of impact on health-related quality of life (HRQoL) and activity. This study examined real-world treatment patterns and humanistic disease burden of MPM in Europe.

Methods

Physicians abstracted demographic/clinical characteristics and treatment data from MPM-patient medical records; MPM patients self-completed a questionnaire including symptoms, 3-level-EQ-5D questionnaire and Visual Analogue Scale (VAS), Lung Cancer Symptom Scale for Mesothelioma (LCSS-Meso), and Work Productivity and Activity Impairment (WPAI) questionnaire.

Results

Physicians (n = 171) abstracted data of 1390 patients; 767/1390 patients self-completed questionnaires. Patients were elderly with advanced, unresectable MPM. Treatment patterns followed guidelines with most (81%) patients receiving platinum+antifolate chemotherapy at first line (1 L). Maintenance treatment use was high (51.1%) despite no recommended maintenance therapies. Symptom burden was high and health states and HRQoL were poor at 1; declining further with progression. Overall mean (SD): LCSS-Average Symptom Burden Index score was 48.8 (19.3; n = 758); EQ-5D Utility Index score was 0.510 (0.349; n = 763); EQ-5D VAS score was 54.2 (20.3;n = 766); LCSS-3-Item Global Index score was 143.2 (64.5; n = 762); LCSS-normal activities score was 51.9 (24.6;n = 765); WPAI-activity impairment was 56.0% (23.2%; n = 737).

Conclusion

The humanistic burden of MPM is high, despite treatments being prescribed as per available guidance. Treatments that delay progression and provide palliation of symptoms are most likely to improve/maintain HRQoL.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09750-7.

Imaging Approach to Disease of the Pleura

Diseases of pleura are not only common but also have a significant impact on patients' outcomes. While early detection and treatment are imperative in reducing this burden, many pleural entities present similarly, thus posing a diagnostic dilemma for radiologists requiring critical further workup. While chest radiography, CT, and image-guided thoracentesis are primarily utilized as the initial imaging techniques for the workup of pleural diseases, MRI, and FDG-PET/CT are also frequently employed to investigate the root cause of pleural abnormalities. By elucidating the common imaging features of neoplastic, inflammatory, and infectious pleural pathologies, clinicians can quickly and easily differentiate the various pleural diseases, rapidly reach the correct diagnosis, and ultimately improve patient outcomes.

Novel Insights Into Mesothelioma Therapy: Emerging Avenues and Future Prospects

Malignant mesothelioma is a rare and aggressive cancer that develops in the thin layer surrounding the mesothelium and is mainly caused by asbestos exposure. Despite improvements in patient prognosis with conventional cancer treatments, such as surgery, chemotherapy, and radiotherapy, there are still no curative treatment modalities for advanced disease. In recent years, new therapeutic avenues have been explored. Improved understanding of the mechanisms underlying the dynamic tumor interaction with the immune system has led to the development of immunotherapeutic approaches. Numerous recent clinical trials have shown a desire to develop more effective treatments that can be used to fight against the disease. Immune checkpoint inhibitors, oncolytic adenoviruses, and their combination represent a promising strategy that can be used to synergistically overcome immunosuppression in the mesothelioma tumor microenvironment. This review provides a synthesized overview of the current state of knowledge on new therapeutic options for mesothelioma with a focus on the results of clinical trials conducted in the field.

Depression and Complicated Grief, and Associated Factors, of Bereaved Family Members of Patients Who Died of Malignant Pleural Mesothelioma in Japan

OBJECTIVES

we investigated the prevalence and associated factors of depression and complicated grief (CG) among bereaved family members of malignant pleural mesothelioma (MPM) patients in Japan.

METHODS

Bereaved family members of MPM patients (n = 72) were surveyed. The Japanese version of the Patient Health Questionnaire-9 (PHQ-9) and the Japanese version of the Brief Grief Questionnaire (BGQ) were used to assess depression and complicated grief (CG), respectively. Socio-economic factors, anger toward asbestos, care satisfaction, achievement of good death, and quality of end-of-life care were assessed in relation to depression and CG.

RESULTS

In the family members of MPM patients, the frequencies of depression and CG were 19.4% and 15.3%, respectively. The bereaved family members who were not compensated by the asbestos-related health-damage relief system (p = 0.018) and who felt the financial impacts of the patient's MPM on the family (p = 0.006) had a higher likelihood of depression. The bereaved family members who were not satisfied with the care given when the patient became critical (p = 0.034), who were not compensated by the asbestos-related health-damage relief system (p = 0.020), who felt the financial impact of the patient's MPM on the family (p = 0.016), and whose deceased relative underwent surgery (p = 0.030) had a higher likelihood of CG.

CONCLUSIONS

For bereaved family members of MPM patients, routine screening for depression and CG and the provision of grief care are suggested. In addition, for family members of MPM patients, financial support, including the promotion of the asbestos-related health-damage relief system, and improved care for patients who undergo surgery and when patients become critical, are recommended.

Repurposing therapeutics for malignant pleural mesothelioma (MPM) - Updates on clinical translations and future outlook

INTRODUCTION

Malignant pleural mesothelioma (MPM) is a rare malignancy affecting the mesothelial cells in the pleural lining surrounding the lungs. First approved chemotherapy against MPM was a platinum/antifolate (cisplatin/pemetrexed) (2003). Since then, no USFDA approvals have gone through for small molecules as these molecules have not been proven to be therapeutically able in later stages of clinical studies. An alternative to conventional chemotherapy can be utilization of monoclonal antibodies, which are proven to improve patient survival significantly as compared to conventional chemotherapy (Nivolumab + Ipilimumab, 2020).

AREA COVERED

Drug repurposing has been instrumental in drug discovery for rare diseases such as MPM and multiple repositioned small molecule therapies and immunotherapies are currently being tested for its applicability in MPM management. This article summarizes essential breakthroughs along the pre-clinical and clinical developmental stages of small molecules and monoclonal antibodies for MPM management.

EXPERT OPINION

For rare diseases such as malignant pleural mesothelioma, a drug repurposing strategy can be adapted as it eases the financial burden on pharmaceutical companies along with fast-tracking development. With the rise of multiple small molecule repurposed therapies and innovations in localized treatment, MPM therapeutics are bound to be more effective in this decade.

Aquaporin-6 May Increase the Resistance to Oxidative Stress of Malignant Pleural Mesothelioma Cells

Malignant pleural mesothelioma (MPM) is an aggressive cancer of the pleural surface and is associated with previous asbestos exposure. The chemotherapy drug is one of the main treatments, but the median survival ranges from 8 to 14 months from diagnosis. The redox homeostasis of tumor cells should be carefully considered since elevated levels of ROS favor cancer cell progression (proliferation and migration), while a further elevation leads to ferroptosis. This study aims to analyze the functioning/role of aquaporins (AQPs) as a hydrogen peroxide (H₂O₂) channel in epithelial and biphasic MPM cell lines, as well as their possible involvement in chemotherapy drug resistance. Results show that AQP-3, -5, -6, -9, and -11 were expressed at mRNA and protein levels. AQP-6 was localized in the plasma membrane and intracellular structures. Compared to normal mesothelial cells, the water permeability of mesothelioma cells is not reduced by exogenous oxidative stress, but it is considerably increased by heat stress, making these cells resistant to ferroptosis. Functional experiments performed in mesothelioma cells silenced for aquaporin-6 revealed that it is responsible, at least in part, for the increase in H₂O₂ efflux caused by heat stress. Moreover, mesothelioma cells knocked down for AQP-6 showed a reduced proliferation compared to mock cells. Current findings suggest the major role of AQP-6 in providing mesothelioma cells with the ability to resist oxidative stress that underlies their resistance to chemotherapy drugs.

Sneaky Diagnosis of Pleural Malignant Mesothelioma in Thoracic Surgery: All That Glitters Is Not Gold

Malignant Pleural Mesothelioma (MPM) is a highly aggressive disease whose diagnosis could be challenging and confusing. It could occur with atypical presentations on every examined level. Here, we present three unconventional cases of the complex diagnostic process of MPM that we have experienced during routine practice: a patient with reactive mesothelial hyperplasia mimicking MPM, an unexpected presentation of MPM with persistent unilateral hydropneumothorax, a rare case of MPM in situ. Then, we review the relevant literature on each of these topics. Definitive biomarkers to confidently distinguish MPM from other pleural affections are still demanded. Patients presenting with persistent hydropneumothorax must always be investigated for MPM. MPM in situ is now a reality, and this raises questions about its management.

Dysregulation of microRNAs and tRNA-derived ncRNAs in mesothelial and mesothelioma cell lines after asbestiform fiber exposure

Experimental evidence demonstrated that fluoro-edenite (FE) can develop chronic respiratory diseases and elicit carcinogenic effects. Environmental exposure to FE fibers is correlated with malignant pleural mesothelioma (MPM). An early diagnosis of MPM, and a comprehensive health monitoring of the patients exposed to FE fibers are two clinical issues that may be solved by the identification of specific biomarkers. We reported the microRNA (miRNA) and transfer RNA-derived non coding RNA (tRNA-derived ncRNA) transcriptome in human normal mesothelial and malignant mesothelioma cell lines exposed or not exposed to several concentration FE fibers. Furthermore, an interactive mesothelioma-based network was derived by using NetME tool. In untreated condition, the expression of miRNAs and tRNA-derived ncRNAs in tumor cells was significantly different with respect to non-tumor samples. Moreover, interesting and significant changes were found after the exposure of both cells lines to FE fibers. The network-based pathway analysis showed several signaling and metabolic pathways potentially involved in the pathogenesis of MPM. From papers analyzed by NetME, it is clear that many miRNAs can positively or negatively influence various pathways involved in MPM. For the first time, the analysis of tRNA-derived ncRNAs molecules in the context of mesothelioma has been made by using in vitro systems. Further studies will be designed to test and validate their diagnostic potential in high-risk individuals' liquid biopsies.

DNA repair and damage pathways in mesothelioma development and therapy

Malignant mesothelioma (MMe) is an aggressive neoplasm that occurs through the transformation of mesothelial cells. Asbestos exposure is the main risk factor for MMe carcinogenesis. Other important etiologies for MMe development include DNA damage, over-activation of survival signaling pathways, and failure of DNA damage response (DDR). In this review article, first, we will describe the most important signaling pathways that contribute to MMe development and their interaction with DDR. Then, the contribution of DDR failure in MMe progression will be discussed. Finally, we will review the latest MMe therapeutic strategies that target the DDR pathway.

CUL4B is a Potential Novel Prognostic Biomarker and is Correlated with Immune Infiltrates in Malignant Pleural Mesothelioma

Background

Methods

Results

Conclusion

[Advances in Immunotherapy for Malignant Pleural Mesothelioma]

Patients with malignant pleural mesothelioma (MPM) usually present with poor prognosis and short survival period, and there has been a lack of effective treatment options for a long time. Chemotherapy has limited improvement in the clinical outcome of advanced patients (the median survival is less than one year), and it is difficult to find suitable targets for targeted therapy. Recent in-depth research on immunotherapy has changed the treatment pattern of MPM. Especially, the dual immunotherapy regimen significantly improved the survival outcome of patients across subgroups and prolonged the survival time of MPM patients. Therefore, it has been approved for unresectable MPM as first-line treatment for patients. The exploration of other mono or combo immunotherapy regimens in the first and second-line settings of MPM is also underway. How to identify the best beneficial population of each regimen through predictive biomarkers is also a hot spot for researchers. This article will focus on the most up-to-date progress of MPM epidemiology, histological characteristics, pathogenesis, treatment patterns and the advances of immunotherapy in the disease.
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Endoscopic Applications of Near-Infrared Photoimmunotherapy (NIR-PIT) in Cancers of the Digestive and Respiratory Tracts

Near-infrared photoimmunotherapy (NIR-PIT) is a newly developed and promising therapy that specifically destroys target cells by irradiating antibody-photo-absorber conjugates (APCs) with NIR light. APCs bind to target molecules on the cell surface, and when exposed to NIR light, cause disruption of the cell membrane due to the ligand release reaction and dye aggregation. This leads to rapid cell swelling, blebbing, and rupture, which leads to immunogenic cell death (ICD). ICD activates host antitumor immunity, which assists in killing still viable cancer cells in the treated lesion but is also capable of producing responses in untreated lesions. In September 2020, an APC and laser system were conditionally approved for clinical use in unresectable advanced head and neck cancer in Japan, and are now routine in appropriate patients. However, most tumors have been relatively accessible in the oral cavity or neck. Endoscopes offer the opportunity to deliver light deeper within hollow organs of the body. In recent years, the application of endoscopic therapy as an alternative to surgery for the treatment of cancer has expanded, providing significant benefits to inoperable patients. In this review, we will discuss the potential applications of endoscopic NIR-PIT, especially in thoracic and gastrointestinal cancers.

The Use of Chest Magnetic Resonance Imaging in Malignant Pleural Mesothelioma Diagnosis

In recent years, many articles have demonstrated that magnetic resonance imaging (MRI) may be performed successfully in the study of the chest. The aim of this study was to evaluate the potential role of MRI in the differentiation of benign from malignant pleural disease with a special focus on malignant pleural mesothelioma and on MRI protocols. A systematic literature search was performed to find original articles about chest MRI in patients with either benign or malignant pleural disease. We retrieved 1246 papers and 17 studies were finally identified as being in accordance with our purpose. For a morphologic assessment, T1-weighted and T2-weighted sequences were usually performed, eventually associated with T1 post-contrast sequences for better detection of pleural lesions. Functional sequences such as Diffusion Weighting Imaging (DWI), associated with the evaluation of Apparent Diffusion Coefficient (ADC) maps, were lately and gradually introduced in chest MRI protocols and their potentiality in differentiating benign from malignant disease has been investigated by many authors. Many progresses have been performed to improve quality images and diagnostic performances of MRI. A better and early identification of pleural disease may be obtained, providing MRI as a possible tool that can differentiate malignant from benign pleural disease without using invasive procedures.

A Redox-Silent Analogue of Tocotrienol May Break the Homeostasis of Proteasomes in Human Malignant Mesothelioma Cells by Inhibiting STAT3 and NRF1

6-O-Carboxypropyl-alpha-tocotrienol (α-T3E) is a multi-target redox-silent analogue of tocotrienol that exhibits cytotoxicity against many cancer cells, including malignant mesothelioma (MM) cells. α-T3E has several molecular targets to effectively induce cytotoxicity against MM cells; however, the mechanisms underlying this cytotoxicity remain unclear. In the present study, we demonstrated that the α-T3E-dependent disruption of the homeostasis of proteasomes strongly induced endoplasmic reticulum (ER) stress, which resulted in effective cytotoxicity against MM cells. The α-T3E-dependent disruption of the homeostasis of proteasomes depended on decreases in proteasome subunits via the inactivation of signal transducer and activator of transcription 3 (STAT3) and nuclear factor erythroid 2 related factor-1 (NRF1), which inhibited protease activity, such as chymotrypsin-like activity, in proteasomes. The α-T3E-dependent inhibition of this activity also induced severe ER stress and ultimately resulted in effective cytotoxicity against MM cells with chemoresistance. The present results indicate that α-T3E acts as an effective anti-mesothelioma agent by disrupting the homeostasis of proteasomes through the simultaneous inactivation of STAT3 and NRF1.

Understanding the Experiences of end of Life Care for Patients with Mesothelioma from the Perspective of Bereaved Family Caregivers in the UK: A Qualitative Analysis

OBJECTIVES

Mesothelioma is a rare, progressive cancer with a short trajectory from diagnosis to the end of life. This study explores the experiences of palliative and end of life care for patients with mesothelioma from the perspective of bereaved family caregivers.

METHODS

A qualitative, descriptive approach was adopted comprising face-to-face, semi-structured interviews with bereaved caregivers of patients with mesothelioma in the UK. An inductive, thematic analysis was conducted using the 'Framework' approach.

RESULTS

Nine bereaved caregivers participated. Four themes emerged: understanding what lies ahead; carer support; care co-ordination; managing after death: practicalities, inquests and abandonment. Caregivers need to understand what lies ahead in order to emotionally and practically prepare themselves for supporting the patient at the end of life. Information and support needs of caregivers were often distinct from those of patients, including the importance of information about the coroner's involvement. The importance of care co-ordination was emphasised, with caregivers valuing on-going relationships and a named individual taking responsibility for co-ordinating the patients care. Feelings of abandonment arose when there was no contact with healthcare professionals following the death of the patient.

CONCLUSIONS

Greater opportunity for open, one-to-one communication between family caregivers and healthcare professionals is vital to enable the caregiver to prepare for what lies ahead at the end of life and prevent feelings of abandonment after the death of the patient. Improved care co-ordination and partnership working are essential for supporting both patient and caregiver at the end of life.

Use of an antagonist of HMGB1 in mice affected by malignant mesothelioma: a preliminary ultrasound and optical imaging study

Background

Malignant mesothelioma (MM) is an aggressive tumor, with a poor prognosis, usually unresectable due to late diagnosis, mainly treated with chemotherapy. BoxA, a truncated form of “high mobility group box 1” (HMGB1), acting as an HMGB1 antagonist, might exert a defensive action against MM. We investigated the potential of BoxA for MM treatment using experimental 40-MHz ultrasound and optical imaging (OI) in a murine model.

Methods

Murine MM cells infected with a lentiviral vector expressing the luciferase gene were injected into the peritoneum of 14 BALB/c mice (7 × 10⁴ AB1-B/c-LUC cells). These mice were randomized to treatment with BoxA (n = 7) or phosphate-buffered saline (controls, n = 7). The experiment was repeated with 40 mice divided into two groups (n = 20 + 20) and treated as above to confirm the result and achieve greater statistical power. Tumor presence was investigated by experimental ultrasound and OI; suspected peritoneal masses underwent histopathology and immunohistochemistry examination.

Results

In the first experiment, none of the 7 controls survived beyond day 27, whereas 4/7 BoxA-treated mice (57.1%) survived up to day 70. In the second experiment, 6/20 controls (30.0%) and 16/20 BoxA-treated mice (80.0%) were still alive at day 34 (p = 0.004). In both experiments, histology confirmed the malignant nature of masses detected using experimental ultrasound and OI.

Conclusion

In our preclinical experience on a murine model, BoxA seems to exert a protective role toward MM. Both experimental ultrasound and OI proved to be reliable techniques for detecting MM peritoneal masses.

KRAS signaling in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) arises from mesothelial cells lining the pleural cavity of asbestos-exposed individuals and rapidly leads to death. MPM harbors loss-of-function mutations in BAP1, NF2, CDKN2A, and TP53, but isolated deletion of these genes alone in mice does not cause MPM and mouse models of the disease are sparse. Here, we show that a proportion of human MPM harbor point mutations, copy number alterations, and overexpression of KRAS with or without TP53 changes. These are likely pathogenic, since ectopic expression of mutant KRASG12D in the pleural mesothelium of conditional mice causes epithelioid MPM and cooperates with TP53 deletion to drive a more aggressive disease form with biphasic features and pleural effusions. Murine MPM cell lines derived from these tumors carry the initiating KRASG12D lesions, secondary Bap1 alterations, and human MPM-like gene expression profiles. Moreover, they are transplantable and actionable by KRAS inhibition. Our results indicate that KRAS alterations alone or in accomplice with TP53 alterations likely play an important and underestimated role in a proportion of patients with MPM, which warrants further exploration.

Malignant pleural mesothelioma patients’ experience by gender: findings from a cross-sectional UK-national questionnaire

Objectives

Malignant mesothelioma is an aggressive malignancy of mesothelial surfaces, most commonly those of the pleura. The aim of this study was to understand, using a national questionnaire, the gendered care experiences of patients with malignant pleural mesothelioma (MPM).

Patients were asked about their experience of the diagnostic process, about information clarity, health care professionals’ knowledge, general practitioner support and overall satisfaction with care received.

Setting

Recruitment of patients was carried out in three UK countries (England, Wales and Scotland) via mesothelioma clinical nurse specialists.

Participants

In total, 503 patients completed the questionnaire. 460 had MPM, the remainder had other types of mesothelioma. In accord with the study protocol, only the MPM patients were included in this study.

Primary and secondary measures were: (1) time from symptom to diagnosis, (2) satisfaction with the diagnosis and treatment, and (3) quality of life and well-being.

Results

There were gender differences in time from symptom to diagnosis. The time from symptom to diagnosis was significantly longer for women than men (median=152 days vs men=92 days, p=0.01). Lack of a verified source of exposure to asbestos was a hindrance to private treatment access for women (95% of those that access private treatment are men). Patients were five times more likely to be satisfied if they thought that the doctors knew enough about their condition (OR=4.4, p=0.001) and nearly three times more likely to be satisfied if information was presented in a sensitive way (OR=2.8, p=0.01).

Conclusions

This study has several implications for clinical practice. Our findings suggest that the diagnostic time in women might be reduced by reviewing diagnostic processes including occupational history taking, and by revising the occupational risk of mesothelioma categorisation.

A role for club cells in smoking-associated lung adenocarcinoma

The cellular origin of lung adenocarcinoma remains a focus of intense research efforts. The marked cellular heterogeneity and plasticity of the lungs, as well as the vast variety of molecular subtypes of lung adenocarcinomas perplex the field and account for the extensive variability of experimental results. While most experts would agree on the cellular origins of other types of thoracic tumours, great controversy exists on the tumour-initiating cells of lung adenocarcinoma, since this histologic subtype of lung cancer arises in the distal pulmonary regions where airways and alveoli converge, occurs in smokers as well as nonsmokers, is likely caused by various environmental agents, and is marked by vast molecular and pathologic heterogeneity. Alveolar type II, club, and their variant cells have all been implicated in lung adenocarcinoma progeny and the lineage hierarchies in the distal lung remain disputed. Here we review the relevant literature in this rapidly expanding field, including results from mouse models and human studies. In addition, we present a case for club cells as cells of origin of lung adenocarcinomas that arise in smokers.

Multiple lung epithelial cells are targets of carcinogenic hits. Club cells are such cells that can metabolically activate tobacco pre-carcinogens, being thus positioned as cells of origin of lung adenocarcinomas in smokers.https://bit.ly/3iOshcy

Preclinical Models and Resources to Facilitate Basic Science Research on Malignant Mesothelioma - A Review

Malignant mesothelioma is an aggressive cancer with poor prognosis, predominantly caused by human occupational exposure to asbestos. The global incidence of mesothelioma is predicted to increase as a consequence of continued exposure to asbestos from a variety of sources, including construction material produced in the past in developed countries, as well as those currently being produced in developing countries. Mesothelioma typically develops after a long latency period and consequently it is often diagnosed in the clinic at an advanced stage, at which point standard care of treatment, such as chemo- and radio-therapy, are largely ineffective. Much of our current understanding of mesothelioma biology, particularly in relation to disease pathogenesis, diagnosis and treatment, can be attributed to decades of preclinical basic science research. Given the postulated rising incidence in mesothelioma cases and the limitations of current diagnostic and treatment options, continued preclinical research into mesothelioma is urgently needed. The ever-evolving landscape of preclinical models and laboratory technology available to researchers have made it possible to study human disease with greater precision and at an accelerated rate. In this review article we provide an overview of the various resources that can be exploited to facilitate an enhanced understanding of mesothelioma biology and their applications to research aimed to improve the diagnosis and treatment of mesothelioma. These resources include cell lines, animal models, mesothelioma-specific biobanks and modern laboratory techniques/technologies. Given that different preclinical models and laboratory technologies have varying limitations and applications, they must be selected carefully with respect to the intended objectives of the experiments. This review therefore aims to provide a comprehensive overview of the various preclinical models and technologies with respect to their advantages and limitations. Finally, we will detail about a highly valuable preclinical laboratory resource to curate high quality mesothelioma biospecimens for research; the biobank. Collectively, these resources are essential to the continued advancement of precision medicine to curtail the increasing health burden caused by malignant mesothelioma.

Nivolumab-induced liver injury with a steroid-refractory increase in biliary enzymes, in a patient with malignant mesothelioma: An autopsy case report

This is the first autopsy report of hepatotoxicity from nivolumab immunotherapy for malignant mesothelioma. The increase in levels of biliary enzymes and randomly distributed endothelial damage were steroid-refractory, but second-line option was abandoned because of cachexia. Further discussions are needed regarding the customized management of immune-related toxicities.

Treatment patterns and outcomes for patients with malignant pleural mesothelioma in England in 2013-2017: A nationwide CAS registry analysis from the I-O Optimise initiative

OBJECTIVES

Malignant pleural mesothelioma (MPM) is a rare and aggressive cancer with a poor prognosis and limited treatment options. This study assessed the characteristics, treatment patterns, and outcomes for patients diagnosed with MPM in England.

MATERIALS AND METHODS

As part of I-O Optimise, this retrospective cohort study analyzed data recorded in the Cancer Analysis System in England for all adult patients newly diagnosed with MPM between 2013 and 2017, with follow-up to March 2018 or death, whichever occurred first. Overall survival (OS) was estimated using Kaplan-Meier methods. A Cox regression model was used to describe the impact of sociodemographic and clinical characteristics at diagnosis on OS.

RESULTS

9458 patients diagnosed with MPM were analyzed. Median age at diagnosis was 75 years; 83.4% were male. Eastern Cooperative Oncology Group performance status (ECOG PS) was 0-1 for 44.5%; 2 for 11.5%; >2 for 9.1%; and missing for 34.9% of patients. TNM stage was missing for 60.4%. A majority of patients had epithelioid histology (36.4%) or not otherwise specified (NOS) MPM (43.3%). After diagnosis, 48.7% of all patients received best supportive care (BSC; no surgery, radiotherapy, SACT); 11.4% received palliative radiotherapy alone; 6.5% underwent surgery; 33.4% received systemic anticancer therapy (SACT) as initial treatment. Platinum plus pemetrexed was the main SACT regimen used in both first and second line. Median OS (8.3 months) varied by histopathology and ranged from 4.3 to 13.3 months for sarcomatoid and epithelioid MPM, respectively. After adjusting for age, sex, and ECOG PS, sarcomatoid, biphasic, and NOS MPM remained significantly associated with worse OS than epithelioid MPM (all p < 0.001). Median OS varied from 4.6 to 17.0 months for patients receiving BSC/palliative radiotherapy, and patients receiving surgery, respectively.

CONCLUSION

Outcomes for patients with MPM in England remain poor. Future studies will investigate the impact of newer therapies on the treatment patterns and survival of MPM patients.

Medical Thoracoscopy

Medical thoracoscopy is an effective and safe modality to visualize and sample contents of the pleural cavity. It is an outpatient procedure that can be performed while the patient is spontaneously breathing, with the use of local anesthesia and intravenous medications for sedation and analgesia. Medical thoracoscopy has indications in the management of a variety of pleural diseases. It is most commonly performed as a diagnostic procedure but has therapeutic applications as well. Although it has its advantages, management strategies of certain pleural diseases should take place within a multidisciplinary environment including general pulmonologists, interventional pulmonologists, and thoracic surgeons.

The Epithelial-to-Mesenchymal Transition (EMT) in the Development and Metastasis of Malignant Pleural Mesothelioma

Malignant pleural mesothelioma (MPM) is an aggressive tumor mainly associated with asbestos exposure and is characterized by a very difficult pharmacological approach. One of the molecular mechanisms associated with cancer onset and invasiveness is the epithelial-to-mesenchymal transition (EMT), an event induced by different types of inducers, such as transforming growth factor β (TGFβ), the main inducer of EMT, and oxidative stress. MPM development and metastasis have been correlated to EMT; On one hand, EMT mediates the effects exerted by asbestos fibers in the mesothelium, particularly via increased oxidative stress and TGFβ levels evoked by asbestos exposure, thus promoting a malignant phenotype, and on the other hand, MPM acquires invasiveness via the EMT event, as shown by an upregulation of mesenchymal markers or, although indirectly, some miRNAs or non-coding RNAs, all demonstrated to be involved in cancer onset and metastasis. This review aims to better describe how EMT is involved in driving the development and invasiveness of MPM, in an attempt to open new scenarios that are useful in the identification of predictive markers and to improve the pharmacological approach against this aggressive cancer.

Improving mesothelioma follow-up care in the UK: a qualitative study to build a multidisciplinary pyramid of care approach

OBJECTIVES

The findings reported in this manuscript are part of a wider study that aimed to explore mesothelioma patients' experiences of follow-up care. The aim of this phase of the study was to co-produce recommendations for policy and practice and to propose a revised, patient-focused, mesothelioma follow-up care service.

DESIGN

The consultation phase was qualitative and consisted of three group discussions with separate stakeholder groups allowing for different priorities and needs for follow-up care to be compared. An implicit approach to consensus was adopted and data were analysed iteratively using the framework method.

SETTING

The study was conducted in three National Health Service Trusts in the South of England. Two were secondary care settings and the third was a tertiary centre.

PARTICIPANTS

The consultation exercise comprised three group discussions with key stakeholders (n=35): mesothelioma specialist nurses (n=9), mesothelioma patients and carers (n=11) and local clinical commissioning group members (n=15).

RESULTS

Recommendations for mesothelioma follow-up care were developed using a co-production approach and highlighted the importance of continuity of care, the provision of timely information and the central role played by mesothelioma specialist nurses, supported by the wider multidisciplinary team. Recommendations were produced together with two bespoke infographics to maximise impact and facilitate patient and public engagement with the study.

CONCLUSIONS

The recommendations developed are the first that specifically examine best practice for the follow-up care pathway for mesothelioma patients. Co-production and public engagement are crucial to priority setting develop and optimising patient-centred care. Combining the recommendations produced with a targeted dissemination strategy and well-designed, patient-focused infographics will maximise opportunities for impact at a regional and national level.