PD‐L1 expression associated with worse survival outcome in malignant pleural mesothelioma

1 Aim

There is currently a need to identify prognostic biomarkers to assist in a risk adopted approach in treatment of malignant pleural mesothelioma (MPM). Expression of programmed death ligand 1 (PD‐L1) has been studied as a prognostic biomarker in a number of tumors given its central role in antitumoral immune response evasion. Four previously published analyses found PD‐L1 positivity to be an adverse survival prognostic factor in MPM. This study aims to further investigate the relationship between PD‐L1 expression in mesothelioma tissues and survival outcome.

2 Methods

Clinical data of MPM patients from a single institution between 2006 and 2016 were reviewed. Patient's archived tissues were stained with PD‐L1 (Clone Ventana SP263). PD‐L1 positivity was defined as > 1% membranous staining regardless of intensity.

3 Results

Data from fifty eight patients were analyzed. Median age was 73, majority was male (49, 84%) and had ECOG between 0 and 2 (46, 79%). Most common histopathological subtype was epithelioid (42, 72%), 9 (16%) biphasic subtype and 7 (12%) sarcomatoid. Thirty one patients (53%) received best supportive care and twenty seven patients (47%) received chemotherapy or combination treatment. Forty‐two patients had positive PD‐L1 expression (72.4%). The median survival time for PD‐L1 negative group is 15.5 months and 6 months for the positive group. Positive PD‐L1 expression is independently correlated with worse prognosis (HR = 2.02; 95% CI, 1.005–4.057; P‐value = 0.0484).

4 Conclusions

Our analysis found a higher percentage of MPM patients with positive PD‐L1 (> 1%) compared to other studies. Highly positive PD‐L1 expression was associated with statistically significantly lower median survival time.     

Intrathoracic latissimus dorsi muscle transposition: a reliable technique for prevention of bronchopleural fistula developing after extrapleural pneumonectomy and external beam radiotherapy in malignant pleural mesothelioma

Objective

Bronchopleural fistula (BPF) is a life threatening complication after pneumonectomy. Extra thoracic skeletal muscle transposition especially latissimus dorsi muscle flap (LDMF) had been used to prevent this complication. The aim of this study was to assess the effectiveness of LDMF in preventing BPF developing after extrapleural pneumonectomy (EPP) and external radiation therapy in malignant pleural mesothelioma (MPM).

Methods

Between May 1999 and Dec. 2008, 37 patients with MPM were operated upon by EPP using LDMF prophylactically to reinforce the bronchial stump, and then received external radiation therapy with or without postoperative chemotherapy.

Results

The mean age of all patients was 46.7 (range 26–57) years. Twenty five patients were males and 12 patients were females. Twenty three patients had MPM of the right side and 14 patients had MPM of the left side. The peri-operative mortality was 2.7% and only few flap related postoperative morbidity were reported in the form of minor seroma and subcutaneous surgical emphysema. The median follow up was 17 (range 9–43) months. All cases completed their postoperative external radiation therapy with no reported cases of early or late BPF.

Conclusion

Intrathoracic pedicled LDMF transposition is proved to be effective in prevention of BPF developing after EPP and external radiation therapy in MPM and it is advised to be a routine step in EPP in these cases and to use more sophisticated technique of postoperative external beam radiotherapy (3D conformal or IMRT) to minimize this complication.     

Characterization of human malignant mesothelioma cell lines orthotopically implanted in the pleural cavity of immunodeficient mice for their ability to grow and form metastasis

Background  

Malignant pleural mesothelioma (MPM) is a tumor known to be resistant to conventional therapies. Thus, an in vivo model can represent an important tool for assessing the efficacy of novel approaches in the treatment of MPM.     

A Phase II Trial of First-Line Combination Chemotherapy With Cisplatin,Pemetrexed, and Nivolumab for Unresectable Malignant Pleural Mesothelioma: A Study Protocol

Background

The purpose of this study is to assess the efficacy and safety of combination chemotherapy with cisplatin, pemetrexed, and nivolumab for unresectable malignant pleural mesothelioma (MPM).

Dysregulated Expression of the MicroRNA miR-137 and Its Target YBX1 Contribute to the Invasive Characteristics of Malignant Pleural Mesothelioma

Introduction

Malignant pleural mesothelioma (MPM) is an aggressive malignancy linked to asbestos exposure. On a genomic level, MPM is characterized by frequent chromosomal deletions of tumor suppressors, including microRNAs. MiR-137 plays a tumor suppressor role in other cancers, so the aim of this study was to characterize it and its target Y-box binding protein 1 (YBX1) in MPM.

Regulation of somatostatin receptor 4-mediated cytostatic effects by CD26 in malignant pleural mesothelioma

Background:

Malignant pleural mesothelioma (MPM) is an aggressive neoplasm arising from mesothelial lining of pleura. CD26 molecules preferentially expressed on epithelioid type of MPM. This study investigates the molecular mechanisms of CD26 regulating MPM cells in vitro and in vivo.

Methods:

Biochemical and cell biological approaches were used for identifying a novel molecular target of MPM. Its contribution to tumour expansion has been also assessed using animal models. The clinical samples of MPM were also assessed for its expression.

Results:

We identify that cytostatic effects in MPM are mediated by somatostatin (SST) receptor 4 (SSTR4), being inhibited by the interaction of CD26 molecules. We also indicates that SSTR4-mediated cytostatic effects are regulated by SHP-2 PTP, and that this inhibitory effect by SST agonist is enhanced via lipid raft clustering of associated molecules following crosslinking of anti-CD26 antibody. Finally, using an in vivo xenograft model, we demonstrate that the anti-tumour effect of anti-CD26 mAb is enhanced when combined with SSTR4 agonist treatment, and that SSTR4 is highly coexpressed with CD26 on epithelioid or biphasic types of MPM tissues obtained from patients'' surgical specimens.

Conclusions:

Combination therapy with humanised anti-CD26 mAb and SSTR4 agonist may therefore potentiate anti-tumour effect on MPM.     

Secretion of intelectin-1 from malignant pleural mesothelioma into pleural effusion

Background:

Malignant pleural mesothelioma (MPM) is a rare but fatal tumour. Although most MPM patients show pleural effusion at even the early stage, it is hard to diagnose as MPM at the early stage because a sensitive and reliable diagnostic marker for MPM has not been found in plasma or pleural effusion.

Methods:

In this study, we investigated whether intelectin-1 was specifically contained in MPM cells and the pleural effusion of MPM patient by immunohistochemistry, western blotting, and enzyme-linked immunosorbent assay.

Results:

Malignant pleural mesothelioma cell lines, but not lung adenocarcinoma cell lines, secreted intelectin-1. In immunohistochemistry, epithelioid-type MPMs, but neither pleura-invading lung adenocarcinomas nor reactive mesothelial cells near the lung adenocarcinomas, were stained with anti-intelectin antibodies. Pleural effusion of MPM patients contained a higher concentration of intelectin-1 than that of lung cancer patients.

Conclusion:

These results suggest that detection of intelectin-1 may be useful for a differential diagnosis of epithelioid-type MPM in immunohistochemistry and that a high concentration of intelectin-1 in pleural effusion can be used as a new marker for clinical diagnosis of MPM.     

Molecular and Histopathological Characterization of the Tumor Immune Microenvironment in Advanced Stage of Malignant Pleural Mesothelioma

Introduction

Malignant pleural mesothelioma (MPM) is a rare, highly aggressive, and relatively chemoresistant and radioresistant malignancy with limited therapeutic options. Our objective was to investigate the prevalence of programmed death ligand 1 (PD-L1) and the characteristics of the immune environment in this disease.

MTA1 promotes metastasis of MPM via suppression of E-cadherin

Background

Metastasis-associated gene 1(MTA1) has been identified as an oncogene in many tumors, and aberrant MTA1 expression has been linked to carcinogenesis and metastasis. We aim to investigate the mechanism of MTA1 and metastasis in malignant pleural mesothelioma (MPM).

Methods

Real-time polymerase chain reaction (PCR) and immunohistochemical staining were employed to detect MTA1 and E-cadherin expression in MPM tissues and corresponding adjacent tissues. Stable clone with knock-down of MTA1 was generated with shRNA via lentivirus technology in MPM cell lines. Wound-healing assay, transwell assay and PCR array were carried out for detecting invasion and migration of MPM cells. Luciferase reporter assay was performed to validate the effect of MTA1 on E-cadherin.

Results

MTA1 expression is up-regulated in MPM and shown a negative correlation with E-cadherin expression. MTA1 could enhance the invasion and migration of MPM cells via suppressing the expression of E-cadherin. MTA1 overexpression is associated with pathology, metastasis and survival rate of MPM patients.

Conclusions

MTA1 plays an important role in Epithelial-to-mesenchymal transition (EMT) to promote metastasis via suppressing E-cadherin expression, resulting in a poor prognosis in MPM. MTA1 is a novel biomarker and indicative of a poor prognosis in MPM patients.

     

Single versus multiple primary melanomas: old questions and new answers

BACKGROUND:

In patients with multiple primary melanomas (MPM), mean tumor thickness tends to decrease from the first melanoma to the second melanoma, and prognosis may be improved compared with the prognosis for patients who have a single primary melanoma (SPM). In this study, the authors compared the clinicopathologic features of patients with MPM and SPM to better characterize the differences between these 2 groups and to determine whether or not there is an inherent difference in tumor aggression.

METHODS:

In total, 788 patients with melanoma who were enrolled prospectively in the Interdisciplinary Melanoma Cooperative Group database from 2002 to 2008 were studied. Patients with SPM and with MPM were compared with regard to clinical and primary melanoma characteristics.

RESULTS:

Of 788 patients with melanoma, 61 patients (7.7%) had 2 or more primary melanomas. The incidence of developing a second primary melanoma 1 year and 5 years after initial melanoma diagnosis was 4.1% and 8.7%, respectively, and most of the risk accumulated within the first year. The incidence of MPM was greater in patients aged ≥60 years than in those aged ≤60 years. The absence or presence of mitosis and other tumor characteristics did not differ significantly between patients with SPM and patients with MPM (P = .61).

CONCLUSIONS:

No difference was observed in the presence or absence of mitoses, a marker of tumor proliferation, in SPM and MPM. Because it has been demonstrated that the presence of mitosis is a powerful prognostic marker, the current findings suggested that the tumors behave similarly in patients with SPM and patients with MPM. The authors concluded that differences in tumor thickness and prognosis between SPM and MPM more likely are caused by factors other than tumor biology, such as increased surveillance. Cancer 2012. © 2012 American Cancer Society.     

A biomarker profile for predicting efficacy of cisplatin–vinorelbine therapy in malignant pleural mesothelioma

Purpose

Malignant pleural mesothelioma (MPM) has a dismal prognosis. Treatment results may be improved by biomarker-directed therapy. We investigated the baseline expression and impact on outcome of predictive biomarkers ERCC1, BRCA1, and class III β-tubulin in a cohort of MPM patients treated with cisplatin–vinorelbine. We further explored the possibility of combining markers into a treatment-response profile to increase the predictive power.

Methods

Formalin-fixed paraffin-embedded tumor specimens from 54 MPM patients included in a phase II trial were evaluated for ERCC1, BRCA1, and class III β-tubulin by immunohistochemistry (IHC). Immunostaining was quantified by an H-score and dichotomized according to upper quartile values. The ERCC1- and class III β-tubulin-status classified patients as treatment resistant (ERCC1 positive?+?class III β-tubulin positive) or treatment responsive (ERCC1 negative?+?class III β-tubulin negative). The remaining marker combinations were considered inconclusive.

Results

Fifty patients had tumor tissue available for IHC. Eleven had a responsive profile, and nine had a resistant profile. Thirty patients had an inconclusive profile. Median progression-free survival (PFS) was 6.7?months in the treatment-resistant group, 15.3?months in the treatment-responsive group, and 8.1?months in the inconclusive group (log-rank p?=?0.03). Multivariate analysis revealed that treatment-resistant patients had a decreased PFS and overall survival (OS) compared with the treatment-responsive patients (HR 6.45, CI 95?% [2.02–20.64] p?=?0.002 and HR 4.64, CI 95?% [1.56–13.79], p?=?0.006, respectively). BRCA1 status was associated with neither PFS nor OS.

Conclusion

Combined negative ERCC1 and class III β-tubulin immunostaining is associated with significantly prolonged PFS and OS in MPM patients receiving cisplatin–vinorelbine therapy.     

Circulating fibrinogen is a prognostic and predictive biomarker in malignant pleural mesothelioma

Background:

To investigate the clinical utility of pretreatment plasma fibrinogen levels in malignant pleural mesothelioma (MPM) patients.

Methods:

A retrospective multicenter study was performed in histologically proven MPM patients. All fibrinogen levels were measured at the time of diagnosis and clinical data were retrospectively collected after approval of the corresponding ethics committees.

Results:

In total, 176 MPM patients (mean age: 63.5 years±10.4 years, 38 females and 138 males) were analysed. Most patients (n=154, 87.5%) had elevated (⩾390 mg dl⁻¹) plasma fibrinogen levels. When patients were grouped by median fibrinogen, patients with low level (⩽627 mg dl⁻¹) had significantly longer overall survival (OS) (19.1 months, confidence interval (CI) 14.5–23.7 months) when compared with those with high level (OS 8.5; CI 6.2–10.7 months). In multivariate survival analyses, fibrinogen was found to be an independent prognostic factor (hazard ratio 1.81, CI 1.23–2.65). Most interestingly, fibrinogen (cutoff 75th percentile per 750 mg dl⁻¹) proved to be a predictive biomarker indicating treatment benefit achieved by surgery within multimodality therapy (interaction term: P=0.034). Accordingly, only patients below the 75th percentile benefit from surgery within multimodality therapy (31.3 vs 5.3 months OS).

Conclusions:

Fibrinogen is a novel independent prognostic biomarker in MPM. Most importantly, fibrinogen predicted treatment benefit achieved by surgery within multimodality therapy.     

An RNAi-based screen reveals PLK1, CDK1 and NDC80 as potential therapeutic targets in malignant pleural mesothelioma

Background:

Malignant pleural mesothelioma (MPM) is an aggressive tumour originating in the thoracic mesothelium. Prognosis remains poor with 9- to 12-month median survival, and new targets for treatments are desperately needed.

Methods:

Utilising an RNA interference (RNAi)-based screen of 40 genes overexpressed in tumours, including genes involved in the control of cell cycle, DNA replication and repair, we investigated potential therapeutic targets for MPM. Following in vitro characterisation of the effects of target silencing on MPM cells, candidates were assessed in tumour samples from 154 patients.

Results:

Gene knockdown in MPM cell lines identified growth inhibition following knockdown of NDC80, CDK1 and PLK1. Target knockdown induced cell-cycle arrest and increased apoptosis. Using small-molecule inhibitors specific for these three proteins also led to growth inhibition of MPM cell lines, and Roscovitine (inhibitor of CDK1) sensitised cells to cisplatin. Protein expression was also measured in tumour samples, with markedly variable levels of CDK1 and PLK1 noted. PLK1 expression in over 10% of cells correlated significantly with a poor prognosis.

Conclusion:

These results suggest that RNAi-based screening has utility in identifying new targets for MPM, and that inhibition of NDC80, CDK1 and PLK1 may hold promise for treatment of this disease.     

Mechanisms of FUS1/TUSC2 deficiency in mesothelioma and its tumorigenic transcriptional effects

Background  

FUS1/TUSC2 is a novel tumor suppressor located in the critical 3p21.3 chromosomal region frequently deleted in multiple cancers. We previously showed that Tusc2-deficient mice display a complex immuno-inflammatory phenotype with a predisposition to cancer. The goal of this study was to analyze possible involvement of TUSC2 in malignant pleural mesothelioma (MPM) - an aggressive inflammatory cancer associated with exposure to asbestos.     

Vinorelbine and gemcitabine as second- or third-line therapy for malignant pleural mesothelioma

Objectives

Pemetrexed-cisplatin is the only FDA-approved regimen for malignant pleural mesothelioma (MPM), and the impact on survival is modest. No drugs have been shown to improve survival as second-line therapy, yet vinorelbine and gemcitabine are prescribed based on the results of small phase II trials. To augment the existing limited data, we examined our institutional experience with vinorelbine and gemcitabine in patients with previously treated MPM.

Materials and methods

We reviewed charts of patients with MPM treated with vinorelbine and/or gemcitabine as second- or third-line therapy between 2003 and 2010. Toxicity was graded according to the Common Terminology Criteria for Adverse Events Version 4.0. CT scans were reviewed with a reference radiologist according to modified RECIST criteria.

Results

Sixty patients were identified: 33 treated with vinorelbine, 15 gemcitabine, and 12 both agents. Eighty-three percent initially received pemetrexed-platinum. Toxicity was substantial: 46% experienced at least one episode of grade 3–4 toxicity. Of 56 patients evaluable radiologically, there was 1 partial response (gemcitabine) giving a response rate of 2% (95% CI: 0–10%). Forty-six percent had stable disease. Median progression free survival was 1.7 months for vinorelbine and 1.6 months for gemcitabine. Median overall survival was 5.4 and 4.9 months, respectively.

Conclusions

Response to second- or third-line vinorelbine or gemcitabine is rare. The high rate of stable disease warrants the continued use of these agents in this setting, though the impact on survival is questionable. These data justify the choice of placebo control arms in randomized trials of novel agents in previously treated patients.     

MDM2 is an important prognostic and predictive factor for platin–pemetrexed therapy in malignant pleural mesotheliomas and deregulation of P14/ARF (encoded by CDKN2A) seems to contribute to an MDM2-driven inactivation of P53

Background:

Malignant pleural mesothelioma (MPM) is a highly aggressive tumour that is first-line treated with a combination of cisplatin and pemetrexed. Until now, predictive and prognostic biomarkers are lacking, making it a non-tailored therapy regimen with unknown outcome. P53 is frequently inactivated in MPM, but mutations are extremely rare. MDM2 and P14/ARF are upstream regulators of P53 that may contribute to P53 inactivation.

Methods:

A total of 72 MPM patients were investigated. MDM2 immunoexpression was assessed in 65 patients. MDM2 and P14/ARF mRNA expression was analysed in 48 patients of the overall collective. The expression results were correlated to overall survival (OS) and progression-free survival (PFS).

Results:

OS and PFS correlated highly significantly with MDM2 mRNA and protein expression, showing a dismal prognosis for patients with elevated MDM2 expression (for OS: Score (logrank) test: P⩽0.002, and for PFS: Score (logrank) test; P<0.007). MDM2 was identified as robust prognostic and predictive biomarker for MPM on the mRNA and protein level. P14/ARF mRNA expression reached no statistical significance, but Kaplan–Meier curves distinguished patients with low P14/ARF expression and hence shorter survival from patients with higher expression and prolonged survival.

Conclusions:

MDM2 is a prognostic and predictive marker for a platin–pemetrexed therapy of patients with MPMs. Downregulation of P14/ARF expression seems to contribute to MDM2-overexpression-mediated P53 inactivation in MPM patients.     

Suppression of activin A signals inhibits growth of malignant pleural mesothelioma cells

Background:

Activins control the growth of several tumour types including thoracic malignancies. In the present study, we investigated their expression and function in malignant pleural mesothelioma (MPM).

Methods:

The expression of activins and activin receptors was analysed by quantitative PCR in a panel of MPM cell lines. Activin A expression was further analysed by immunohistochemistry in MPM tissue specimens (N=53). Subsequently, MPM cells were treated with activin A, activin receptor inhibitors or activin-targeting siRNA and the impact on cell viability, proliferation, migration and signalling was assessed.

Results:

Concomitant expression of activin subunits and receptors was found in all cell lines, and activin A was overexpressed in most cell lines compared with non-malignant mesothelial cells. Similarly, immunohistochemistry demonstrated intense staining of tumour cells for activin A in a subset of patients. Treatment with activin A induced SMAD2 phosphorylation and stimulated clonogenic growth of mesothelioma cells. In contrast, treatment with kinase inhibitors of activin receptors (SB-431542, A-8301) inhibited MPM cell viability, clonogenicity and migration. Silencing of activin A expression by siRNA oligonucleotides further confirmed these results and led to reduced cyclin D1/3 expression.

Conclusion:

Our study suggests that activin A contributes to the malignant phenotype of MPM cells via regulation of cyclin D and may represent a valuable candidate for therapeutic interference.     

A Phase 1b/2 trial of mapatumumab in patients with relapsed/refractory non-Hodgkin's lymphoma

Background:

We conducted a multicentre Phase 1b/2 trial to evaluate the safety and efficacy of mapatumumab, a fully human agonistic monoclonal antibody to the tumour necrosis factor-related apoptosis-inducing ligand receptor 1 (TRAIL-R1) in patients with relapsed non-Hodgkin''s lymphoma (NHL).

Methods:

Forty patients with relapsed or refractory NHL were treated with either 3 or 10 mg kg⁻¹ mapatumumab every 21 days. In the absence of disease progression or prohibitive toxicity, patients received a maximum of six doses.

Results:

Mapatumumab was well tolerated, with no patients experiencing drug-related hepatic or other dose-limiting toxicity. Three patients with follicular lymphoma (FL) experienced clinical responses, including two with a complete response and one with a partial response. Immunohistochemistry staining of the TRAIL-R1 suggested that strong staining in tumour specimens did not appear to be a requirement for mapatumumab activity in FL.

Conclusions:

Mapatumumab is safe and has promising clinical activity in patients with FL.     

Programmed Death 1 Blockade With Nivolumab in Patients With Recurrent Malignant Pleural Mesothelioma

Introduction

Malignant pleural mesothelioma (MPM) has limited treatment options and a poor outcome. Programmed death 1/programmed death ligand 1 (PD-L1) checkpoint inhibitors have proven efficacious in several cancer types. Nivolumab is a fully humanized monoclonal antibody against programmed death 1 with a favorable toxicity profile. In MPM, the immune system is considered to play an important role. We therefore tested nivolumab in recurrent MPM.

Gemcitabine and vinorelbine as second-line or beyond treatment in patients with malignant pleural mesothelioma pretreated with platinum plus pemetrexed chemotherapy

Background

Malignant pleural mesothelioma (MPM) is an aggressive neoplasm that responds poorly to chemotherapy. Although treatment with pemetrexed in combination with cisplatin serves as first-line chemotherapy for MPM, the optimal second-line and beyond therapy has not yet been fully examined.

Methods

Between March 2008 and October 2011, 17 consecutive Japanese patients pretreated with at least one regimen of platinum plus pemetrexed chemotherapy received gemcitabine and vinorelbine. Responses, survival time, and toxicity were retrospectively evaluated.

Results

Response [partial response (PR) + complete response (CR)] and disease control [stable disease (SD) + PR + CR] rates were 18 and 82 %, respectively. The median progression-free survival (PFS) after combination chemotherapy was 6.0 months, whereas the median overall survival (OS) was 11.2 months. Grade 3 or 4 neutropenia and anemia were observed in 41 and 29 % of patients, respectively, and one patient experienced febrile neutropenia. Grade 3 or 4 nonhematologic toxicities included constipation (6 %) and phlebitis (6 %).

Conclusion

Combination chemotherapy using gemcitabine with vinorelbine was shown to have moderate activity in Japanese MPM patients pretreated with platinum plus pemetrexed chemotherapy. A further multicenter phase II trial is warranted to confirm the efficacy and safety of this combination treatment.