Kao SC, Yan TD, Lee K, Burn J, Henderson DW, Klebe S, Kennedy C, Vardy J, Clarke S, van Zandwijk N, McCaughan BC.

Asbestos Diseases Research Institute, Bernie Banton Centre, Sydney, Australia.

Abstract

Introduction: Histological subtype is an established prognostic factor in malignant pleural mesothelioma (MPM). We retrospectively investigated the accuracy of classifying histological subtype on diagnostic biopsies and examined the impact of different diagnostic procedures on the outcome.

Methods: Consecutive patients with histologically confirmed MPM who underwent extrapleural pneumonectomy (EPP) from 1994 to 2009 were included. Patient records were reviewed, and the initial diagnoses of histological subtype were obtained. The archival EPP specimens were reviewed by a panel of pathologists. The histological subtype obtained at review was compared with the initial diagnosis.

Results: Eighty-five patients underwent EPP. Two patients achieved a pathological complete response after neoadjuvant chemotherapy, leaving 83 patients to be included in this review. Different diagnostic methods were used before EPP: 81% thoracoscopy; 7% thoracotomy; 11% computed tomography-guided procedure; and 1% other. Patients determined to have an epithelial subtype (n = 64) at EPP were diagnosed correctly at initial diagnostic biopsy in 84% of cases, whereas patients considered to have a biphasic subtype (n = 19) at EPP were diagnosed correctly at diagnostic biopsy in 26% of cases. The sensitivity and specificity of diagnostic biopsy for epithelial MPM was 93% and 31%, respectively. The overall subtype misclassification rate was 20%. Biopsy by thoracotomy was most accurate in subtype classification (83%) compared with thoracoscopy (74%) and computed tomography-guided procedure (44%).

Conclusions: The determination of histological subtype from a diagnostic biopsy is difficult due to sampling error, but an adequate specimen obtained from surgical biopsy increases the accuracy of subtype classification compared with radiological-guided biopsies.

Greillier L, Marco S, Barlesi F.

Service d’Oncologie Multidisciplinaire et Innovations Thérapeutiques, Université de la Méditerranée-Assistance Publique Hôpitaux de Marseille, Marseille, France.

Abstract

Malignant pleural mesothelioma (MPM) is an aggressive tumor with poor prognosis, whose exposure to asbestos fibers is the main etiology. The incidence of MPM is anticipated to increase worldwide during the first half of this century. MPM is notoriously refractory to most treatments, and the only standard of care is cisplatin and antifolate first-line chemotherapy. The urgent need for additional therapeutic agents, in parallel with advances in the knowledge of the molecular events of oncogenesis, has resulted in the development of the so-called ‘targeted agents’ that specifically inhibit critical pathways in malignant cells and in their microenvironment. We carried out a comprehensive review of the literature from January 2000 to May 2010 on studies that assessed targeted agents for the systemic treatment of MPM. Although tyrosine kinase inhibitors directed against the epidermal growth factor and the platelet-derived growth factor receptors did not show significant clinical activity in phase II studies, some other targeted therapies seemed promising, notably histone deacetylase inhibitors and antiangiogenic agents. However, none of these has yet reached daily practice. That is the reason why efforts must continue in the area of clinical and translational research for MPM.

Zucali PA, Giovannetti E, Destro A, Mencoboni M, Ceresoli GL, Gianoncelli L, Lorenzi E, De Vincenzo F, Simonelli M, Perrino M, Bruzzone A, Thunnissen E, Tunesi G, Giordano L, Roncalli M, Peters GJ, Santoro A.

Department of Oncology, Biostatistics Unit, Istituto Clinico Humanitas IRCCS, Rozzano, Milan, Italy. paolo.zucali@humanitas.it

Abstract

Purpose: The pemetrexed/platinum agent combination represents the standard of care in first-line treatment for malignant pleural mesothelioma (MPM). However, there are no established indicators of responsiveness that can be used to optimize the treatment. This retrospective study aimed to assess the role of excision repair cross-complementing group-1 (ERCC1) and thymidylate synthase (TS) in tumors, and correlate expression levels and polymorphisms of these key determinants of drug activity with the outcome of MPM patients treated with carboplatin/pemetrexed in first-line setting. Experimental design: Analysis of TS and ERCC1 polymorphisms, mRNA and protein expression was done by PCR and immunohistochemistry [with the H-score (histologic score)] in tumor specimens from 126 MPM patients, including 99 carboplatin-/pemetrexed-treated patients.

Results: A significant correlation between low TS protein expression and disease control (DC) to carboplatin/pemetrexed therapy (P = 0.027), longer progression-free survival (PFS; P = 0.017), and longer overall survival (OS; P = 0.022) was found when patients were categorized according to median H-score. However, patients with the higher tertile of TS mRNA expression correlated with higher risk of developing progressive disease (P = 0.022), shorter PFS (P < 0.001), and shorter OS (P < 0.001). At multivariate analysis, the higher tertile of TS mRNA level and TS H-score confirmed their independent prognostic role for DC, PFS, and OS. No significant associations were found among ERCC1 protein expression, TS and ERCC1 polymorphisms, and clinical outcome.

Conclusions: In our series of carboplatin-/pemetrexed-treated MPM patients, low TS protein and mRNA levels were significantly associated to DC, improved PFS, and OS. Prospective trials for the validation of the prognostic/predictive role of TS in MPM patients treated with pemetrexed-based regimens are warranted.

Demmy TL, Platis IE, Nwogu C, Yendamuri S.

Department of Thoracic Surgery, Roswell Park Cancer Institute, Buffalo, New York.

Abstract

Mesothelioma is the most common primary pleural malignancy. Surgical therapy offers limited cure benefits at the cost of high morbidity. Although technically challenging and performed rarely, a less invasive approach to extrapleural pneumonectomy was developed with the intent to speed convalescence, hasten adjuvant therapies, improve quality of life, and reduce wound surface area for possible tumor contamination.

Murakami H, Mizuno T, Taniguchi T, Fujii M, Ishiguro F, Fukui T, Akatsuka S, Horio Y, Hida T, Kondo Y, Toyokuni S, Osada H, Sekido Y.

Authors’ Affiliations: Division of Molecular Oncology, Aichi Cancer Center Research Institute; Departments of Thoracic Surgery and Thoracic Oncology, Aichi Cancer Center Hospital; Departments of Cardio-Thoracic Surgery and Cancer Genetics, Program in Function Construction Medicine, and Pathology and Biological Responses, Nagoya University Graduate School of Medicine, Nagoya, Japan.

Abstract

Malignant mesothelioma (MM) is an aggressive neoplasm associated with asbestos exposure. We carried out genome-wide array-based comparative genomic hybridization analysis with 14 MM cell lines. Three cell lines showed overlapping homozygous deletion at chromosome 13q12, which harbored the LATS2 (large tumor suppressor homolog 2) gene. With 6 other MM cell lines and 25 MM tumors, we found 10 inactivating homozygous deletions or mutations of LATS2 among 45 MMs. LATS2 encodes a serine/threonine kinase, a component of the Hippo tumor-suppressive signaling pathway, and we transduced LATS2 in MM cells with its mutation. Transduction of LATS2 inactivated oncoprotein YAP, a transcriptional coactivator, via phosphorylation, and inhibited MM cell growth. We also analyzed LATS2 immunohistochemically and found that 13 of 45 MM tumors had low expression of LATS2. Because NF2 is genetically mutated in 40% to 50% of MM, our data indicate that Hippo pathway dysregulation is frequent in MM cells with inactivation of LATS2 or an upstream regulator of this pathway, Merlin, which is encoded by NF2. Thus, our results suggest that the inactivation of LATS2 is one of the key mechanisms for constitutive activation of YAP, which induces deregulation of MM cell proliferation.

Ou WB, Hubert C, Corson JM, Bueno R, Flynn DL, Sugarbaker DJ, Fletcher JA.

Department of Pathology, Brigham and Women’s Hospital, Boston, MA, USA.

Abstract

The receptor tyrosine kinases (RTKs) epidermal growth factor receptor (EGFR) and MET are activated in subsets of mesothelioma, suggesting that these kinases might represent novel therapeutic targets in this notoriously chemotherapy-resistant cancer. However, clinical trials have shown little activity for EGFR inhibitors in mesothelioma. Despite the evidence for RTK activation in mesothelioma pathogenesis, it is unclear whether transforming activity is dependent on an individual kinase oncoprotein or the coordinated activity of multiple kinases. Using phospho-RTK and immunoblot assays, we herein demonstrate activation of multiple RTKs (EGFR, MET, AXL, and ERBB3) in individual mesothelioma cell lines but not in normal mesothelioma cells. Inhibition of mesothelioma multi-RTK signaling was accomplished using combinations of RTK direct inhibitors or by inhibition of the RTK chaperone, heat shock protein 90 (HSP90). Multi-RTK inhibition by the HSP90 inhibitor 17-allyloamino-17-demethoxygeldanamycin (17-AAG) had a substantially greater effect on mesothelioma proliferation and survival compared with inhibition of individual activated RTKs. HSP90 inhibition also suppressed phosphorylation of downstream signaling intermediates (AKT, mitogen-activated protein kinase, and S6); upregulated the p53, p21, and p27 cell cycle checkpoints; induced G(2) phase arrest; induced caspase 3/7 activity; and led to an increase in the sub-G(1) apoptotic population. These compelling proapoptotic and antiproliferative responses indicate that HSP90 inhibition warrants clinical evaluation as a novel therapeutic strategy in mesothelioma.

Zardo P, Zhang R, Wiegmann B, Haverich A, Fischer S.

Department of Thoracic Surgery and Lung Assist, Klinikum Ibbenbüren, Ibbenbüren, Germany.

Abstract

Background: We sought to analyze the efficacy of a bovine pericardial patch (PeriGuard®) for diaphragmatic repair.

Methods: Seven consecutive patients (6 males, median age 56 years) scheduled for diaphragmatic resection and/or repair were enrolled in this study. In all cases diaphragmatic repair was performed with a PeriGuard Repair Patch® (Synovis, St. Paul, MN, USA). At follow-up (median: 12 months; range: 6-18 months), quality of life, signs of reherniation and incorporation of mesh were assessed through clinical examination, blood samples and CT or MRT scan.

Results: Diagnosis on admission included sarcoma (n = 2), mesothelioma (n = 1), squamous cell carcinoma (n = 1), parachordoma (n = 1) and large congenital or posttraumatic herniation (n = 2). At follow-up successful diaphragmatic repair with no signs of reherniation, graft dehiscence or seroma formation was confirmed for all patients. Recorded inflammatory markers [C-reactive protein (CRP), white blood cell count (WBC) and procalcitonin (PCT)] reached their peak values between postoperative day (POD) 4 and POD 7. Values ranged from 122-282 mg/L for CRP, 0.4-4.6 µg/L for PCT and 6.2-15.6 Tsd/µL for WBC. Overall oncological results were good and 5 out of 6 survivors reported a fully reestablished quality of life.

Conclusion: We consider the PeriGuard Repair Patch® a viable alternative to synthetic materials for diaphragm replacement. Moreover, we advise carrying out cautious follow-up in patients undergoing extensive oncological resection to learn more about the biological behavior of the bovine PeriGuard Repair Patch® after diaphragmatic repair.

Gnoni A, Marech I, Silvestris N, Vacca A, Lorusso V.

Medical Oncology Unit, Hospital Vito Fazzi – Lecce, Italy. vitolorusso@inwind.it.

Abstract

Dasatinib (BMS-354825, Sprycel®) is an oral, multitargeted inhibitor of receptor tyrosine kinases (RTKs), including BCR-ABL fusion protein, stem cell factor receptor (c-KIT), platelet-derived growth factor receptor (PDGFR), and Src family kinases (SFKs). Several early- and late-phase clinical trials for chronic myelogeneous leukaemia (CML) have demonstrated the direct inhibition of BCR-ABL fusion protein and SFKs, which led to dasatinib approval by the Food and Drug Administration (FDA) and the European Union for the treatment of imatinib-resistant or -intolerant CML, and Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL). Phase III dose-optimization study was performed to compare different regimens, stating that dasatinib 100 mg once daily is now the recommended schedule for patients with chronic CML, and 140 mg once daily for patients with accelerated phase or myeloid or lymphoid blast phase CML, and for patients with Ph+ ALL until progression. Because of the myriad of critical roles of SFKs in biological processes, SFKs inhibition could induce numerous biological responses. Ongoing clinical trials evaluate dasatinib in the treatment of several solid tumours, including gastrointestinal stromal tumours (GIST), prostate cancer, malignant pleural mesothelioma, sarcomas, NSCLC, colorectal cancer, glioblastoma and other haematologic malignances as multiple myeloma. Ongoing pre-clinical studies assess the therapeutic potential of dasatinib in other solid tumours, including melanoma, head and neck cancer, breast cancer and ovarian cancer. Dasatinib is generally well tolerated. Myelosuppression is the common adverse event which is, however, reversible by dose reduction, discontinuation, or interruption. Thrombocytopenia is more significant than neutropenia and associated to gastrointestinal bleeding and CNS haemorrhage. The most common non-haematologic adverse events include gastrointestinal symptoms (diarrhoea, nausea, vomiting, abdominal pain and anorexia), headache, peripheral edema, and pleural effusion. In respect of these encouraging studies investigating dasatinib in the treatment of patients with GIST, prostate cancer, multiple myeloma and sarcomas, ongoing phase III clinical trials warrant the drug evaluation as recommended agent for the treatment of these diseases, also in association with chemoterapy or other targeted therapies.

Zhong J, Lardinois D, Szilard J, Tamm M, Roth M.

Pulmonary Cell Research, Department Biomedicine, University Hospital Basel, Petersgraben 4, CH-4031 Basel, Switzerland.

Abstract

Pleural malignant mesothelioma is a rare but deadly tumour mainly induced by asbestos inhalation. Despite the ban of asbestos in 1990 in 52 countries, mesothelioma cases still increase worldwide. In pleural mesothelioma, p38 mitogen activated protein kinases (MAPK) have been suggested to play a major role in carcinogenesis and aggressiveness of tumours. The aim of this study was to determine the role of the different four p38 MAPK isoforms and their effect on proliferation together with the underlying signalling pathways in a rat pleural mesothelioma cell line. Rat pleural mesothelioma cells were stimulated with platelet-derived growth factor (PDGF)-BB and/or transforming growth factor beta (TGF)-β. MAPK and transcription factor expression and activation was monitored in the cytosol and nucleus by immuno-blotting. Proliferation was determined by manual cell count and siRNAs were used to control MAPK and transcription factor expression and action. Only PDGF-BB, but not TGF-β1 induced proliferation via activated Erk1/2 and p38 MAPK. The p38α and δ isoforms were expressed in the cytosol, and upon activation p38δ translocated into the nucleus, while p38α remained in the cytosol. No other p38 isoform was expressed by rat mesothelioma cells. C/EBP-α was found in both the cytosol and the nucleus, while C/EBP-β was not expressed at all. PDGF-BB induced proliferation was suppressed by down-regulation of either Erk1/2, or p38δ MAPK, or C/EBP-α. Furthermore, TGF-β inhibited PDGF-BB induced proliferation by interruption of p38 MAPK signalling. From this rat model, we conclude that in pleural mesothelioma, p38δ in C/EBP-α mediate proliferation and thus may represent new targets in mesothelioma therapy.

Yonemura Y, Tsukiyama G, Miyata R, Sako S, Endou Y, Hirano M, Mizumoto A, Matsuda T, Takao N, Ichinose M, Miura M, Hagiwara A, Li Y.

NPO Organization to Support Peritoneal Dissemination Treatment.

Abstract

A total of 521 patients with peritoneal carcinomatosis (PC) were treated by peritonectomy and perioperative chemotherapy. Each of the 95, 58, 316, 31, 10 and 11 patients were from gastric, colorectal, appendiceal, ovarian, small bowel cancer and mesothelioma, respectively. The distribution and volume of PC are recorded by the Sugarbaker peritoneal carcinomatosis index( PCI). Peritonectomy was performed with a radical resection of the primary tumor and all gross PC with involved organs, peritoneum, or tissue that was deemed technically feasible and safe for the patient. The postoperative major complication of grade 3 was found in 14%, and total 30 – day mortality was 2.7%. The survival of gastric cancer patients with a PCI score ≤ 6 was significantly better than those with a PCI score ≥ 7. In appendiceal neoplasm, patients with PCI score less than 28 showed significantly better survival than those with PCI score greater than 29. The survival of colorectal cancer patients with a PCI score ≥ 11 was significantly poorer than those with a PCI score ≤ 10. Among the various prognostic factors in appendiceal neoplasm and gastric cancer patients, CC – 0 complete cytoreduction was the most important independent prognostic factor. Peritonectomy is done to remove macroscopic disease and perioperative intraperitoneal chemotherapy to eradicate microscopic residual disease aiming to remove disease completely with a single procedure. Peritonectomy combined with perioperative chemotherapy may achieve long – term survival in a selected group of patients with PC. The higher mortality rate underlines this necessarily strict selection that should be reserved to experienced institutions.