Real world efficacy and toxicity of consolidation durvalumab following chemoradiotherapy in older Australian patients with unresectable stage III non-small cell lung cancer.

INTRODUCTION: Consolidation durvalumab following platinum-based chemoradiotherapy (CRT) significantly improved overall survival for patients with unresectable stage III non-small cell lung cancer (NSCLC) in the PACIFIC trial. However, older patients were underrepresented in PACIFIC, and subsequent analyses suggested trends toward poorer survival and increased toxicity in patients aged ≥70 years old. We assessed the effectiveness and safety of consolidation durvalumab following CRT in older Australian patients with unresectable stage III NSCLC. MATERIALS AND METHODS: This retrospective observational study was conducted across seven sites in Sydney, Australia between January 2018 and September 2021. All adult patients with unresectable stage III NSCLC who received platinum-based chemoradiotherapy followed by at least one cycle of consolidation durvalumab were included. Older patients were defined as being ≥70 years old. RESULTS: Of 152 patients included in the analysis, 42.8% (n = 67) patients were 70 years or older. Median follow-up was 26.1 months. The two-year overall survival and median PFS was similar between older and younger patients. At two years, 74.8% (95% confidence interval [CI]: 65.4-84.2%) of patients <70 years old and 65.2% (95% CI: 53.4-77.0%) of older patients were alive (p = 0.07; hazard ratio [HR] 1.64, 95% CI: 0.95-2.81). Median progression-free survival (PFS) in patients <70 years was 30.3 months (95% CI: 22.2-38.4 months) compared with 26.7 months (95% CI: 12.8-40.6 months) in older patients (p = 0.22; HR 1.46, 95% CI: 0.80-2.65). Toxicity was also similar, with 11.5% of patients <70 years old and 18.5% of older patients experiencing grade 3-4 adverse events (AEs; p = 0.23); 16.1% and 24.6% of the patients, respectively, discontinued treatment due to toxicity (p = 0.19). Grade 3-4 AEs and treatment discontinuation were associated with Charlson Comorbidity Index >5 (p = 0.011) and chronic obstructive pulmonary disease diagnosis at presentation (p = 0.002), respectively. DISCUSSION: Older Australian patients receiving consolidation durvalumab following CRT experienced comparable outcomes to their younger peers. Comorbidity burden may be more important determinants of treatment tolerance than chronological age.

High mesothelin expression by immunohistochemistry predicts improved survival in pleural mesothelioma.

AIMS: Mesothelin (MSLN) is a cancer-associated antigen that is overexpressed in malignancies such as mesothelioma, pancreatic and ovarian cancer. It is also a target for novel personalised therapies, including antibodies, antibody-drug conjugates and chimeric antigen receptor T cells. Immunohistochemistry may predict those who would best respond to anti-mesothelin therapies and guide decisions in therapeutic strategy. This study aimed to assess the intensity and distribution of MSLN immunostaining in mesothelioma, and to determine the prognostic value of MSLN expression by histochemical-score (H-score). METHODS AND RESULTS: The MN1 anti-MSLN antibody was used to stain a formalin-fixed paraffin-embedded tissue microarray of histologically confirmed mesothelioma from 75 consecutive patients who had undergone pleurectomy with or without decortication. MSLN positivity, the staining intensity, distribution of staining and H-score were evaluated. The correlation of H-score with prognosis was investigated. Sixty-six per cent of epithelioid tumours were MSLN-positive (with expression in > 5% tumour cells). Of MSLN-expressing epithelioid tumours, 70.4% had moderate (2+) or strong (3+) intensity MSLN immunostaining, although only 37% of samples had staining in ≥ 50% of tumour cells. In multivariate analysis, MSLN H-score as a continuous variable and an H-score ≥ 33 were independent predictors of improved survival (P = 0.04 and P < 0.001, respectively). CONCLUSIONS: MSLN expression was more heterogenous in epithelioid mesothelioma than reported previously. Therefore, it would be appropriate to perform an immunohistochemical assessment of MSLN expression to stratify and assess patient suitability for mesothelin-targeted personalised therapies, such as chimeric antigen receptor T cells.

Lidocaine for Neuropathic Cancer Pain (LiCPain): study protocol for a mixed-methods pilot study.

INTRODUCTION: Many patients experience unrelieved neuropathic cancer-related pain. Most current analgesic therapies have psychoactive side effects, lack efficacy data for this indication and have potential medication-related harms. The local anaesthetic lidocaine (lignocaine) has the potential to help manage neuropathic cancer-related pain when administered as an extended, continuous subcutaneous infusion. Data support lidocaine as a promising, safe agent in this setting, warranting further evaluation in robust, randomised controlled trials. This protocol describes the design of a pilot study to evaluate this intervention and explains the pharmacokinetic, efficacy and adverse effects evidence informing the design. METHODS AND ANALYSIS: A mixed-methods pilot study will determine the feasibility of an international first, definitive phase III trial to evaluate the efficacy and safety of an extended continuous subcutaneous infusion of lidocaine for neuropathic cancer-related pain. This study will comprise: a phase II double-blind randomised controlled parallel-group pilot of subcutaneous infusion of lidocaine hydrochloride 10% w/v (3000 mg/30 mL) or placebo (sodium chloride 0.9%) over 72 hours for neuropathic cancer-related pain, a pharmacokinetic substudy and a qualitative substudy of patients' and carers' experiences. The pilot study will provide important safety data and help inform the methodology of a definitive trial, including testing proposed recruitment strategy, randomisation, outcome measures and patients' acceptability of the methodology, as well as providing a signal of whether this area should be further investigated. ETHICS AND DISSEMINATION: Participant safety is paramount and standardised assessments for adverse effects are built into the trial protocol. Findings will be published in a peer-reviewed journal and presented at conferences. This study will be considered suitable to progress to a phase III study if there is a completion rate where the CI includes 80% and excludes 60%. The protocol and Patient Information and Consent Form have been approved by Sydney Local Health District (Concord) Human Research Ethics Committee 2019/ETH07984 and University of Technology Sydney ETH17-1820. TRIAL REGISTRATION NUMBER: ANZCTR ACTRN12617000747325.

3-Dimensional mesothelioma spheroids provide closer to natural pathophysiological tumor microenvironment for drug response studies.

Traditional studies using cancer cell lines are often performed on a two-dimensional (2D) cell culture model with a low success rate of translating to Phase I or Phase II clinical studies. In comparison, with the advent of developments three-dimensional (3D) cell culture has been championed as the latest cellular model system that better mimics in vivo conditions and pathological conditions such as cancer. In comparison to biospecimens taken from in vivo tissue, the details of gene expression of 3D culture models are largely undefined, especially in mesothelioma - an aggressive cancer with very limited effective treatment options. In this study, we examined the veracity of the 3D mesothelioma cell culture model to study cell-to-cell interaction, gene expression and drug response from 3D cell culture, and compared them to 2D cell and tumor samples. We confirmed via SEM analysis that 3D cells grown using the spheroid methods expressed highly interconnected cell-to-cell junctions. The 3D spheroids were revealed to be an improved mini-tumor model as indicated by the TEM visualization of cell junctions and microvilli, features not seen in the 2D models. Growing 3D cell models using decellularized lung scaffold provided a platform for cell growth and infiltration for all cell types including primary cell lines. The most time-effective method was growing cells in spheroids using low-adhesive U-bottom plates. However, not every cell type grew into a 3D model using the the other methods of hanging drop or poly-HEMA. Cells grown in 3D showed more resistance to chemotherapeutic drugs, exhibiting reduced apoptosis. 3D cells stained with H&E showed cell-to-cell interactions and internal architecture that better represent that of in vivo patient tumors when compared to 2D cells. IHC staining revealed increased protein expression in 3D spheroids compared to 2D culture. Lastly, cells grown in 3D showed very different microRNA expression when compared to that of 2D counterparts. In conclusion, 3D cell models, regardless of which method is used. Showed a more realistic tumor microenvironment for architecture, gene expression and drug response, when compared to 2D cell models, and thus are superior preclinical cancer models.

GUIDE: a randomised non-comparative phase II trial of biomarker-driven intermittent docetaxel versus standard-of-care docetaxel in metastatic castration-resistant prostate cancer (clinical trial protocol).

Objective: To determine the efficacy and safety of intermittent docetaxel chemotherapy guided by circulating methylated glutathione S-transferase Pi-1 (mGSTP1) in men with metastatic castration-resistant prostate cancer (CRPC). Patients and Methods: GUIDE (NCT04918810) is a randomised, two-arm, non-comparative phase-2 trial recruiting 120 patients at six Australian centres. Patients with Prostate Cancer Working Group-3 defined metastatic CRPC who are commencing docetaxel 75 mg/m2 q3w will be pre-screened for detectable mGSTP1 at baseline ± following two cycles of treatment. Those with detectable plasma mGSTP1 at baseline that becomes undetectable after two cycles of chemotherapy will be eligible for GUIDE. Prior to Cycle 4 of docetaxel, these patients are randomised 2:1 to one of two treatment arms: Arm A (cease docetaxel and reinstitute if mGSTP1 becomes detectable) or Arm B (continue docetaxel 75 mg/m2 q3w in accordance with clinician's usual practice). The primary endpoint is radiographic progression-free survival. Secondary endpoints include time on treatment holidays, safety, patient-reported outcomes, overall survival, health resource use, and cost associated with treatment. Enrolment commenced November 2021. Results and Conclusion: The results of this trial will generate data on the clinical utility of mGSTP1 as a novel biomarker to guide treatment de-escalation in metastatic CRPC.

The minimum standard of care for managing malignant pleural mesothelioma in developing nations within the Asia-Pacific Region.

Malignant pleural mesothelioma (MPM) is an incurable malignancy associated with high symptom burden and poor prognosis. The relationship between asbestos exposure and MPM incidence is well-established. The incidence rate of MPM in Australia and New Zealand is among the highest globally. Matching the experience of other nations with legal restrictions on asbestos, incidence is expected to fall. In contrast, the incidence of MPM is rising in the developing nations of the Asia-Pacific as consumption and mining (albeit to a lesser extent) of asbestos continues. The incidence of MPM in these nations is currently low or unknown, reflecting insufficient latency periods since industrial use of asbestos, deficient resources for accurate diagnosis, and lack of occupational disease or cancer registries. The landscape of treatment for MPM is rapidly changing with combination immunotherapy now demonstrating improved survival in the first-line setting. Considering vast global inequity in access to anticancer treatments, establishing minimum standard of care for MPM in developing nations is of greater significance. Here, we review the evidence that form the basis of our minimum-standard recommendations for diagnosis, systemic treatment, management of recurrent pleural effusions, and symptom management. We also briefly review evidence-based treatment that may be considered for those with access.

The Role of E-Cadherin and microRNA on FAK Inhibitor Response in Malignant Pleural Mesothelioma (MPM).

Malignant pleural mesothelioma (MPM) is an aggressive malignancy with limited effective treatment options. Focal adhesion kinase (FAK) inhibitors have been shown to efficiently suppress MPM cell growth initially, with limited utility in the current clinical setting. In this study, we utilised a large collection of MPM cell lines and MPM tissue samples to study the role of E-cadherin (CDH1) and microRNA on the efficacy of FAK inhibitors in MPM. The immunohistochemistry (IHC) results showed that the majority of MPM FFPE samples exhibited either the absence of, or very low, E-cadherin protein expression in MPM tissue. We showed that MPM cells with high CDH1 mRNA levels exhibited resistance to the FAK inhibitor PND-1186. In summary, MPM cells that did not express CDH1 mRNA were sensitive to PND-1186, and MPM cells that retained CDH1 mRNA were resistant. A cell cycle analysis showed that PND-1186 induced cell cycle disruption by inducing the G2/M arrest of MPM cells. A protein-protein interaction study showed that EGFR is linked to the FAK pathway, and a target scan of the microRNAs revealed that microRNAs (miR-17, miR221, miR-222, miR137, and miR148) interact with EGFR 3'UTR. Transfection of MPM cells with these microRNAs sensitised the CHD1-expressing FAK-inhibitor-resistant MPM cells to the FAK inhibitor.

Evaluation of a Mainstream Model of Genetic Testing for Men With Prostate Cancer.

PURPOSE: To identify the approximately 12% with inherited cancer predisposition, all men with metastatic prostate cancer (mPC) should be offered germline genetic testing. This guides treatment choices and impacts cancer prevention in the family. Limited genetic services globally present a barrier to testing. This study tested a potential solution, "mainstreaming," where counseling and testing are performed by the patient's oncologist. PATIENTS AND METHODS: Men with mPC at three Australian sites were offered germline genetic testing at their medical oncology appointment. Panel testing (ATM, BRCA1, BRCA2, BRIP1, CHEK2, EPCAM, FANCA, HOXB13, MLH1, MSH2, MSH6, NBN, PALB2, PMS2, RAD51D, and TP53) was performed on saliva/blood (Invitae, San Francisco, CA). Primary outcomes were clinician and patient satisfaction. Secondary outcomes included mutation rates and resource allocation. RESULTS: Of 66 men offered testing, 63 (95%) accepted. Four pathogenic variants were identified (two BRCA2, one NBN, and one MSH6). Fifty patients and nine clinicians completed questionnaires. Satisfaction was high. All patients were pleased to have had testing overall, 98% (46 of 47) to have had testing at their usual oncology appointment, and all to receive results from their usual specialist, rather than a separate genetics appointment. A total of 88% (7 of 8) of clinicians felt confident, and all were satisfied with mainstreaming. Mainstreaming was resource efficient, requiring 87% fewer genetic consultations than traditional genetic counseling. CONCLUSION: This study demonstrates that mainstreaming of men with mPC is feasible, resource efficient, and satisfactory for clinicians and patients. Widespread implementation as standard of care would facilitate timely access to genetic testing for men with mPC.

CDKN2A and MTAP Are Useful Biomarkers Detectable by Droplet Digital PCR in Malignant Pleural Mesothelioma: A Potential Alternative Method in Diagnosis Compared to Fluorescence In Situ Hybridisation.

BACKGROUND: The diagnosis of malignant pleural mesothelioma (MPM) can be difficult, in part due to the difficulty in distinguishing between MPM and reactive mesothelial hyperplasia (RMH). The tumor suppressor gene, CDKN2A, is frequently silenced by epigenetic mechanisms in many cancers; in the case of MPM it is mostly silenced via genomic deletion. Co-deletion of the CDKN2A and methylthioadenosine phosphorylase (MTAP) genes has been researched extensively and discovered to be a highly specific characteristic of MPM. Most studies have used FISH to detect the deletion of CDKN2A and IHC for MTAP as a surrogate for this. In this study, we aim to investigate and validate droplet digital PCR (ddPCR) as an emerging alternative and efficient testing method in diagnosing MPM, by particularly emphasizing on the loss of MTAP and CDKN2A. METHODS: This study included 75 formalin fixed paraffin embedded (FFPE) MPM tissue, and 12 normal pleural tissue and 10 RMH as control. Additionally, primary MPM cell lines and normal pleural samples were used as biomarker detection controls, as established in our previous publication. All FFPE specimens were processed to isolate the DNA, that was subsequently used for ddPCR detection of CDKN2A and MTAP. FFPE samples were also analyzed by fluorescence in situ hybridization (FISH) for CDKN2A and MTAP deletion, and for MTAP IHC expression. Concordance of IHC and ddPCR with FISH were studied in these samples. RESULTS: 95% and 82% of cases showed co-deletion of both MTAP and CDKN2A when determined by FISH and ddPCR respectively. ddPCR has a sensitivity of 72% and specificity of 100% in detecting CDKN2A homozygous loss in MPM. ddPCR also has a concordance rate of 92% with FISH in detecting homozygous loss of CDKN2A. MTAP IHC was 68% sensitive and 100% specific for detecting CDKN2A homozygous loss in MPM when these losses were determined by ddPCR. CONCLUSION: Our study confirms that MTAP is often co-deleted with CDKN2A in MPM. Our in-house designed ddPCR assays for MTAP and CDKN2A are useful in differentiating MPM from RMH, and is highly concordant with FISH that is currently used in diagnosing MPM. ddPCR detection of these genetic losses can potentially be utilized as an alternative method in the diagnosis of MPM and for the future development of a less-invasive MPM-specific detection technique on MPM tumor tissue DNA.

The Current Understanding Of Asbestos-Induced Epigenetic Changes Associated With Lung Cancer.

Asbestos is a naturally occurring mineral consisting of extremely fine fibres that can become trapped in the lungs after inhalation. Occupational and environmental exposures to asbestos are linked to development of lung cancer and malignant mesothelioma, a cancer of the lining surrounding the lung. This review discusses the factors that are making asbestos-induced lung cancer a continuing problem, including the extensive historic use of asbestos and decades long latency between exposure and disease development. Genomic mutations of DNA nucleotides and gene rearrangements driving lung cancer are well-studied, with biomarkers and targeted therapies already in clinical use for some of these mutations. The genes involved in these mutation biomarkers and targeted therapies are also involved in epigenetic mechanisms and are discussed in this review as it is hoped that identification of epigenetic aberrations in these genes will enable the same gene biomarkers and targeted therapies to be used. Currently, understanding of how asbestos fibres trapped in the lungs leads to epigenetic changes and lung cancer is incomplete. It has been shown that oxidoreduction reactions on fibre surfaces generate reactive oxygen species (ROS) which in turn damage DNA, leading to genetic and epigenetic alterations that reduce the activity of tumour suppressor genes. Epigenetic DNA methylation changes associated with lung cancer are summarised in this review, and some of these changes will be due to asbestos exposure. So far, little research has been carried out to separate the asbestos driven epigenetic changes from those due to non-asbestos causes of lung cancer. Asbestos-associated lung cancers exhibit less methylation variability than lung cancers in general, and in a large proportion of samples variability has been found to be restricted to promoter regions. Epigenetic aberrations in cancer are proving to be promising biomarkers for diagnosing cancers. It is hoped that further understanding of epigenetic changes in lung cancer can result in useful asbestos-associated lung cancer biomarkers to guide treatment. Research is ongoing into the detection of lung cancer epigenetic alterations using non-invasive samples of blood and sputum. These efforts hold the promise of non-invasive cancer diagnosis in the future. Efforts to reverse epigenetic aberrations in lung cancer by epigenetic therapies are ongoing but have not yet yielded success.

High BIN1 expression has a favorable prognosis in malignant pleural mesothelioma and is associated with tumor infiltrating lymphocytes.

OBJECTIVES: A number of key immune regulators show prognostic value in malignant pleural mesothelioma (MPM), but the association between Bridging integrator 1 (BIN1), indoleamine 2,3 dioxygenase 1 (IDO1) and patient outcome has not been investigated. We aimed to determine the expression of BIN1 and IDO1, their association with other markers and impact on overall survival (OS) in MPM. MATERIALS AND METHODS: The expression of BIN1, IDO1, CD3, CD20 and CD68 were evaluated by immunohistochemistry in 67 patients who underwent pleurectomy/decortication. Survival analyses were performed using the Kaplan Meier method and significant biomarkers were entered into a Cox Regression multivariate model, accounting for known prognostic factors such as age, gender, histological subtype, PD-L1 expression and neutrophil-to-lymphocyte ratio. RESULTS: Immune markers were variably expressed in tumor cells, ranging from 0% to 100% for BIN1 (median: 89%), and 0% to 77.5% for IDO1 (median: 0%). Expression of markers of tumor-infiltrating lymphocytes (TILs) and macrophages ranged from 0% to more than 50%. BIN1 expression was high in 35 patients (51%) and was associated with increased OS (median: 12 vs 6 months for high and low BIN1 respectively,p = 0.03). Multivariate analysis showed BIN1 remained an independent prognostic indicator (HR 0.39; 95% CI: 0.18-0.82, p = 0.01). The majority of patients had immune inflamed tumors (77%) and there was a significant association between TILs and BIN1 (p = 0 < 0.01), PD-L1 (p=0.04) and CD68+ macrophages in the tumor (p < 0.01). There were no significant associations between PD-L1 and BIN1 or IDO1. CONCLUSION: High BIN1 expression is a favorable prognostic biomarker and is associated with TILs in MPM.

Patterns of care and survival of older patients with malignant pleural mesothelioma.

OBJECTIVE: Malignant pleural mesothelioma (MPM) is a cancer that primarily affects older adults. However this patient population is frequently under-represented in clinical studies. Therefore, we studied the impact of advancing age on treatment utilisation and clinical outcomes in an extensive series of minimally selected MPM patients. MATERIALS AND METHODS: Patients with MPM receiving compensation from the New South Wales (NSW) Dust Diseases Authority (2002-2009) were assessed. They were categorised by age (<70 years, 70-80 years or > 80 years) and chi-square testing was used to assess the relationship between clinical and demographic variables, age, treatment and overall survival (OS). RESULTS: We identified 910 patients; 41% were aged <70 years, 40% were aged 70-80 years, and 19% were aged >80 years old. Median OS decreased with increasing age: 13.5 months in <70 years, 9.5 months in 70-80 years and 7.1 months in >80 years as did chemotherapy use (66%, 35% and 8% respectively). Radical surgical intervention, adjuvant, and palliative radiotherapy were less frequently used with advanced age. A Kaplan Meier analysis revealed that there was a significant survival advantage (p < .001) for patients <70 and 70-80 years receiving chemotherapy (16.8 vs 7.0 months; 13.9 vs 5.8 months respectively), but not for patients >80 years. CONCLUSION: Advancing age group of NSW patients with MPM was associated with reduced treatment utilisation and a decline in OS. Prospective studies are warranted to verify if current treatment guidelines are relevant for the older adults with 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. METHODS: Expression, methylation, and copy number status of miR-137 and its host gene MIR137HG were assessed by polymerase chain reaction. Luciferase reporter assays confirmed a direct interaction between miR-137 and Y-box binding protein 1 gene (YBX1). Cells were transfected with a miR-137 inhibitor, miR-137 mimic, and/or YBX1 small interfering RNA, and growth, colony formation, migration and invasion assays were conducted. RESULTS: MiR-137 expression varied among MPM cell lines and tissue specimens, which was associated with copy number variation and promoter hypermethylation. High miR-137 expression was linked to poor patient survival. The miR-137 inhibitor did not affect target levels or growth, but interestingly, it increased miR-137 levels by means of mimic transfection suppressed growth, migration, and invasion, which was linked to direct YBX1 downregulation. YBX1 was overexpressed in MPM cell lines and inversely correlated with miR-137. RNA interference-mediated YBX1 knockdown significantly reduced cell growth, migration, and invasion. CONCLUSIONS: MiR-137 can exhibit a tumor-suppressive function in MPM by targeting YBX1. YBX1 knockdown significantly reduces tumor growth, migration, and invasion of MPM cells. Therefore, YBX1 represents a potential target for novel MPM treatment strategies.

Safety and activity of microRNA-loaded minicells in patients with recurrent malignant pleural mesothelioma: a first-in-man, phase 1, open-label, dose-escalation study.

BACKGROUND: TargomiRs are minicells (EnGeneIC Dream Vectors) loaded with miR-16-based mimic microRNA (miRNA) and targeted to EGFR that are designed to counteract the loss of the miR-15 and miR-16 family miRNAs, which is associated with unsuppressed tumour growth in preclinical models of malignant pleural mesothelioma. We aimed to assess the safety, optimal dosing, and activity of TargomiRs in patients with malignant pleural mesothelioma. METHODS: In this first-in-man, open-label, dose-escalation phase 1 trial at three major cancer centres in Sydney (NSW, Australia), we recruited adults (aged ≥18 years) with a confirmed diagnosis of malignant pleural mesothelioma, measurable disease, radiological signs of progression after previous chemotherapy, Eastern Cooperative Oncology Group performance status of 0 or 1, life expectancy of 3 months or more, immunohistochemical evidence of tumour EGFR expression, and adequate bone marrow, liver, and renal function. Patients were given TargomiRs via 20 min intravenous infusion either once or twice a week (3 days apart) in a traditional 3 + 3 dose-escalation design in five dose cohorts. The dose-escalation steps planned were 5 × 109, 7 × 109, and 9 × 109 TargomiRs either once or twice weekly, but after analysis of data from the first eight patients, all subsequent patients started protocol treatment at 1 × 109 TargomiRs. The primary endpoints were to establish the maximum tolerated dose of TargomiRs as measured by dose-limiting toxicity, define the optimal frequency of administration, and objective response (defined as the percentage of assessable patients with a complete or partial response), duration of response (defined as time from the first evidence of response to disease progression in patients who achieved a response), time to response (ie, time from start of treatment to the first evidence of response) and overall survival (defined as time from treatment allocation to death from any cause). Analyses were based on the full analysis set principle, including every patient who received at least one dose of TargomiRs. The study was closed for patient entry on Jan 3, 2017, and registered with ClinicalTrials.gov, number NCT02369198, and the Australian Registry of Clinical Trials, number ACTRN12614001248651. FINDINGS: Between Sept 29, 2014, and Nov 24, 2016, we enrolled 27 patients, 26 of whom received at least one TargomiR dose (one patient died before beginning treatment). Overall, five dose-limiting toxicities were noted: infusion-related inflammatory symptoms and coronary ischaemia, respectively, in two patients given 5 × 109 TargomiRs twice weekly; anaphylaxis and cardiomyopathy, respectively, in two patients given 5 × 109 TargomiRs once weekly but who received reduced dexamethasone prophylaxis; and non-cardiac pain in one patient who received 5 × 109 TargomiRs once weekly. We established that 5 × 109 TargomiRs once weekly was the maximum tolerated dose. TargomiR infusions were accompanied by transient lymphopenia (25 [96%] of 26 patients), temporal hypophosphataemia (17 [65%] of 26 patients), increased aspartate aminotransferase or alanine aminotranferase (six [23%] of 26 patients), and increased alkaline phosphatase blood concentrations (two [8%]). Cardiac events occurred in five patients: three patients had electrocardiographic changes, one patient had ischaemia, and one patient had Takotsubo cardiomyopathy. Of the 22 patients who were assessed for response by CT, one (5%) had a partial response, 15 (68%) had stable disease, and six (27%) had progressive disease. The proportion of patients who achieved an objective response was therefore one (5%) of 22, and the duration of the objective response in that patient was 32 weeks. Median overall survival was 200 days (95% CI 94-358). During the trial, 21 deaths occurred, of which 20 were related to tumour progression and one was due to bowel perforation. INTERPRETATION: The acceptable safety profile and early signs of activity of TargomiRs in patients with malignant pleural mesothelioma support additional studies of TargomiRs in combination with chemotherapy or immune checkpoint inhibitors. FUNDING: Asbestos Diseases Research Foundation.

Tumor Suppressor microRNAs Contribute to the Regulation of PD-L1 Expression in Malignant Pleural Mesothelioma.

INTRODUCTION: The upregulation of programmed death ligand 1 (PD-L1) is found in many cancers and contributes to evasion of the host's immune defense. In malignant pleural mesothelioma (MPM), PD-L1 expression is associated with the nonepithelioid histological subtype and poor prognosis, but the pathways involved in control of PD-L1 expression in MPM are poorly understood. To address one possible means of PD-L1 regulation we investigated the relationship between dysregulated microRNA levels and PD-L1 expression. METHODS: PD-L1 expression was analyzed by immunohistochemistry in tissue microarrays prepared from samples from patients undergoing an operation (pleurectomy with or without decortication). MicroRNA expression was analyzed by reverse-transcriptase quantitative polymerase chain reaction. Regulation of PD-L1 expression in cell lines was assessed after transfection with microRNA mimics and small interfering RNAs. Interaction between microRNAs and PD-L1 was analyzed by using argonaute-2 immunoprecipitation and a luciferase reporter assay. RESULTS: In a series of 72 patients with MPM, 18 (25%) had positive PD-L1 staining, and this was more common in patients with the nonepithelioid subtype (p = 0.01). PD-L1 expression was associated with poor survival (median overall survival 4.0 versus 9.2 months with positive versus negative PD-L1 expression [p < 0.001]), and in multivariate analyses, PD-L1 expression remained a significant adverse prognostic indicator (hazard ratio = 2.2, 95% confidence interval: 1.2-4.1, p < 0.01). In the same patient series, PD-L1 expression was also associated with downregulation of microRNAs previously shown to have tumor suppressor activity in MPM. The median microRNA expression levels of miR-15b, miR-16, miR-193a-3p, miR-195, and miR-200c were significantly lower in the PD-L1-positive samples. Transfecting MPM cell lines with mimics corresponding to miR-15a and miR-16, both of which are predicted to target PD-L1, led to downregulation of PD-L1 mRNA and protein. In addition, miR-193a-3p, with an alternative G-U-containing target site, also caused PD-L1 downregulation. CONCLUSIONS: Together, these data suggest that tumor suppressor microRNAs contribute to the regulation of PD-L1 expression in MPM.

Geographic and socioeconomic factors in patients with malignant pleural mesothelioma in New South Wales and their impact upon clinical outcomes.

BACKGROUND AND OBJECTIVE: Whilst the impact of clinicopathological factors on the prognosis of malignant pleural mesothelioma (MPM) is well understood, socioeconomic and geographic factors have received less attention. We analysed the relationship between geographic and socioeconomic factors upon survival and treatment provision in a large series of patients with MPM. METHODS: We assessed MPM patients awarded compensation between 2002 and 2009 with additional MPM incidence data from the New South Wales (NSW) Cancer Registry. The impact of geographic remoteness, distance from oncological multidisciplinary team (MDT) and Index of Relative Socioeconomic Advantage and Disadvantage (IRSAD) upon survival, clinical features and treatment received was analysed. RESULTS: We identified 910 patients (67% residing in major cities; 92% <50 km from MDT). Median overall survival was 10.0 months. On multivariate analysis, age >70 (hazard ratio (HR) = 1.39), male gender (HR =1.36), non-epithelioid histological subtype (HR = 2.18) and IRSAD status by decreasing quintile (HR = 1.06) were independent prognostic factors. There was no significant advantage for patients residing in major cities (10.6 months vs 8.8 months; P = 0.162) or within 50 km of MDT (10.3 months vs 7.8 months; P = 0.539). Patient's geographic location and distance to MDT did not impact chemotherapy, adjuvant radiotherapy or extrapleural pneumonectomy provision. Socioeconomically disadvantaged patients were significantly less likely to receive chemotherapy (37.4% vs 54.8%; P = 0.001). CONCLUSION: This study provides evidence for differences in the treatment and survival according to socioeconomic status for compensated MPM patients in NSW. Further research is warranted to seek additional explanations for the differences noted by comparing the treatments and outcomes of compensated and non-compensated MPM patients in NSW.

miR-193a-3p is a potential tumor suppressor in malignant pleural mesothelioma.

Malignant pleural mesothelioma (MPM) is an asbestos-induced cancer with poor prognosis that displays characteristic alterations in microRNA expression. Recently it was reported that the expression of a subset of microRNAs can distinguish between MPM and adenocarcinoma of the lung. However, the functional importance of these changes has yet to be investigated. We compared expression of miR-192, miR-193a-3p and the miR-200 family in normal pleura and MPM tumor specimens and found a statistically significant reduction in the levels of miR-193a-3p (3.1-fold) and miR-192 (2.8-fold) in MPM. Transfection of MPM cells with a miR-193a-3p mimic resulted in inhibition of growth and an induction of apoptosis and necrosis in vitro. The growth inhibitory effects of miR-193a-3p were associated with a decrease in MCL1 expression and were recapitulated by RNAi-mediated MCL1 silencing. Targeted delivery of miR-193a-3p mimic using EDV minicells inhibited MPM xenograft tumour growth, and was associated with increased apoptosis. In conclusion, miR-193a-3p appears to have importance in the biology of MPM and may represent a target for therapeutic intervention.

MiR-score: a novel 6-microRNA signature that predicts survival outcomes in patients with malignant pleural mesothelioma.

BACKGROUND: Prognosis of malignant pleural mesothelioma (MPM) is poor, and predicting the outcomes of treatment is difficult. Here we investigate the potential of microRNA expression to estimate prognosis of MPM patients. METHODS: Candidate microRNAs from microarray profiling of tumor samples from 8 long (median: 53.7 months) and 8 short (median: 6.4 months) survivors following extrapleural pneumonectomy (EPP) were validated by RT-qPCR in 48 additional EPP samples. Kaplan-Meier log ranking was used to further explore the association between microRNA expression and overall survival (OS). Binary logistic regression was used to construct a microRNA signature (miR-Score) that was able to predict an OS of ≥20 months. Performance of the miR-Score was evaluated by receiver operating characteristic (ROC) curve analysis and validated in a series of 43 tumor samples from patients who underwent palliative surgery [pleurectomy/decortication (P/D)]. RESULTS: The miR-Score, using expression data of six microRNAs (miR-21-5p, -23a-3p, -30e-5p, -221-3p, -222-3p, and -31-5p), enabled prediction of long survival with an accuracy of 92.3% for EPP and 71.9% for palliative P/D. Hazard ratios for score-negative patients were 4.12 (95% CI: 2.03-8.37) for EPP and 1.93 (95% CI: 1.01-3.69) for P/D. Importantly, adding the miR-Score to a set of clinical selection criteria (histology, age, gender) increased predictive accuracy in the independent validation set from 76.3% for clinical factors only to 87.3%. CONCLUSIONS: This study has identified a novel 6-microRNA signature (miR-Score) that can accurately predict prognosis of MPM patients.

Glasgow prognostic score as a prognostic factor in metastatic castration-resistant prostate cancer treated with docetaxel-based chemotherapy.

BACKGROUND: The modified Glasgow Prognostic Score (mGPS), derived from C-reactive protein (CRP) and albumin levels, and the neutrophil-lymphocyte ratio (NLR) have demonstrated prognostic significance in a number of malignancies. PATIENTS AND METHODS: Baseline mGPS and NLR were calculated in a prospective cohort of chemotherapy-naive patients with metastatic castration-resistant prostate cancer (mCRPC) (AT-101-CS-205 trial) who received docetaxel and prednisone ± AT101. Cox proportional hazards regression models estimated their effects on overall survival (OS). RESULTS: Of 220 eligible patients, mGPS and neutrophil and lymphocyte counts were available for 184, 193, and 112 patients, respectively. Albumin (hazard ratio [HR], 0.28; 95% confidence interval [CI]: 0.14-0.56; P < .001) and CRP (HR, 1.22; 95% CI, 1.00-1.48; P = .048) were independently prognostic for OS. An association between mGPS and OS was found (HR, 1.87; 95% CI, 1.35-2.59; P < .001; median survival, 23.5 months at mGPS 0 vs. 9.8 months at mGPS 2). mGPS was significant after controlling for 3 previously published nomograms or NLR (P ≤ .001). NLR was not prognostic for OS (HR, 0.98; P = .91), and no association between mGPS and toxicity was noted. CONCLUSION: Our results demonstrate the prognostic role of the mGPS in mCRPC over variables previously identified. mGPS is inexpensive, easily measured, and could be incorporated into routine clinical testing if our results are confirmed in a subsequent validation study. The utility of the NLR in mCRPC remains uncertain despite evidence in other malignancies.

Immunohistochemistry in the diagnosis of malignant pleural mesothelioma: trends in Australia and a literature review.

AIMS: The accurate diagnosis of malignant pleural mesothelioma (MPM) is essential for therapeutic and legal reasons. In 2006 the International Mesothelioma Panel advocated the use of a panel, including two mesothelial and two non-mesothelial immunohistochemical (IHC) markers. We assessed the changing use of IHC for the diagnosis of MPM in Australia over two decades in the context of current best practice. METHODS: Patients with a confirmed clinico-pathological diagnosis of MPM who underwent extrapleural pneumonectomy or pleurectomy and/or decortication between 1988 and 2006 were identified from the cardiothoracic database at Royal Prince Alfred Hospital and combined with consecutive patients reviewed by the Dust Diseases Board between March 2007 and March 2009. Initial diagnostic pathology reports were reviewed. RESULTS: A total of 289 patients were identified. A median of six IHC stains per sample was performed (range 0-18): two (range 0-5) mesothelial markers, two (0-6) carcinoma markers and two epithelial markers. A trend to the higher usage of antibodies in epithelioid tumors versus biphasic and sarcomatoid tumors was noted (P = 0.148 and 0.389, respectively). Testing increased from a median of three stains per sample (1988-1997) to seven (2006-2009). Labeling specimens with > 2 mesothelial markers and > 2 carcinoma markers increased to 72 and 67 percent, respectively, after 2006. CONCLUSION: Reflecting the acceptance of diagnostic panels and increased availability of antibodies, an increase in the use of IHC stains for MPM diagnosis has occurred over the past two decades although uncertainty persists as to the optimal panel composition.