Ioannis Psallidas

A Central Role for Tumor-derived Monocyte Chemoattractant Protein-1 in Malignant Pleural Effusion

BACKGROUND Tumor cells in malignant pleural effusions (MPEs) are an important source of monocyte chemoattractant protein (MCP)-1. However, the role of tumor-derived MCP-1 in the pathogenesis and progression of MPE has not been determined. METHODS B16 mouse skin melanoma cells, which are deficient in MCP-1 expression, and mouse Lewis lung cancer (LLC) cells, which express high levels of MCP-1, were engineered to stably express MCP-1 and short hairpin RNAs (shRNAs) targeting the MCP-1 transcript, respectively. Cells were injected into the pleural cavities of syngeneic immunocompetent mice, and MPE volume and pleural tumors were quantified at necropsy (day 14). MCP-1 and other mediators were determined by cytometric bead array and enzyme-linked immunosorbent assay, and mononuclear and endothelial cells were identified by immunolabeling of F4/80 and factor VIII-related antigen respectively. Mouse survival was assessed using Kaplan-Meier analysis. Vascular permeability in mice with MPE was assessed using albumin-binding Evans blue. Statistical tests were two-sided. RESULTS LLC cells expressing shRNA against MCP-1 elaborated less than 5% of the MCP-1 level in cells expressing nonspecific shRNA (control cells), and intrapleural delivery of these cells resulted in less MPE (mean MPE volume = 86 and 585 muL, respectively; difference = 499 muL; 95% confidence interval [CI] = 331 to 669 muL; P < .001), reduced MCP-1 levels in the pleural fluid, and lower mortality than when control cells were delivered. Overexpression of MCP-1 in intrapleurally injected B16 melanoma cells led to increased MPE and reduced survival. In mice with MPE, MCP-1 was a potent inducer of vascular permeability, mononuclear recruitment, and, in pleural tumors, of angiogenesis. CONCLUSION MCP-1 produced by tumor cells is an important determinant of their capacity to induce the formation of MPE and may be a useful target for the treatment of malignant pleural disease.

Tumor Necrosis Factor-α Promotes Malignant Pleural Effusion

Tumor necrosis factor (TNF)-α is present in the microenvironment of human tumors, including malignant pleural effusion (MPE). Although the cytokine is produced in the pleural cavity by both tumor and host cells, its effects on MPE formation are unknown. In these studies, we sought to determine the role of TNF-α in the pathogenesis of MPE and to assess the therapeutic effects of its neutralization in a preclinical model. For this, MPEs were generated in immunocompetent mice using intrapleural injection of mouse lung adenocarcinoma cells. The roles of tumor- and host-derived TNF-α were assessed using combined experimentation with TNF-α gene–deficient mice and in vivo TNF-α neutralization. To expand the scope of preclinical data, TNF-α and vascular endothelial growth factor (VEGF) expression were determined in human cancer cell lines and human MPE. In the MPE model, TNF-α of host and tumor origin was present. TNF-α neutralization significantly limited tumor dissemination, effusion formation, vascular hyperpermeability, TNF-α and VEGF expression, and angiogenesis, thereby improving survival. In contrast, these variables were not different between TNF-α gene–sufficient and TNF-α gene–deficient mice. In mouse cancer cells, TNF-α functioned via nuclear factor-κB– and neutral sphingomyelinase–dependent pathways to induce TNF-α and VEGF, respectively. These results were recapitulated in human cancer cells, and a correlation was detected between TNF-α and VEGF content of human MPE. We conclude that tumor-derived TNF-α is important in the development of MPE in mice, and provide preclinical evidence supporting the efficacy of TNF-α blockade against malignant pleural disease. [Cancer Res 2007;67(20):9825–34]

Effect of Opioids vs NSAIDs and Larger vs Smaller Chest Tube Size on Pain Control and Pleurodesis Efficacy Among Patients With Malignant Pleural Effusion: The TIME1 Randomized Clinical Trial.

IMPORTANCE For treatment of malignant pleural effusion, nonsteroidal anti-inflammatory drugs (NSAIDs) are avoided because they may reduce pleurodesis efficacy. Smaller chest tubes may be less painful than larger tubes, but efficacy in pleurodesis has not been proven. OBJECTIVE To assess the effect of chest tube size and analgesia (NSAIDs vs opiates) on pain and clinical efficacy related to pleurodesis in patients with malignant pleural effusion. DESIGN, SETTING, AND PARTICIPANTS A 2×2 factorial phase 3 randomized clinical trial among 320 patients requiring pleurodesis in 16 UK hospitals from 2007 to 2013. INTERVENTIONS Patients undergoing thoracoscopy (n = 206; clinical decision if biopsy was required) received a 24F chest tube and were randomized to receive opiates (n = 103) vs NSAIDs (n = 103), and those not undergoing thoracoscopy (n = 114) were randomized to 1 of 4 groups (24F chest tube and opioids [n = 28]; 24F chest tube and NSAIDs [n = 29]; 12F chest tube and opioids [n = 29]; or 12F chest tube and NSAIDs [n = 28]). MAIN OUTCOMES AND MEASURES Pain while chest tube was in place (0- to 100-mm visual analog scale [VAS] 4 times/d; superiority comparison) and pleurodesis efficacy at 3 months (failure defined as need for further pleural intervention; noninferiority comparison; margin, 15%). RESULTS Pain scores in the opiate group (n = 150) vs the NSAID group (n = 144) were not significantly different (mean VAS score, 23.8 mm vs 22.1 mm; adjusted difference, -1.5 mm; 95% CI, -5.0 to 2.0 mm; P = .40), but the NSAID group required more rescue analgesia (26.3% vs 38.1%; rate ratio, 2.1; 95% CI, 1.3-3.4; P = .003). Pleurodesis failure occurred in 30 patients (20%) in the opiate group and 33 (23%) in the NSAID group, meeting criteria for noninferiority (difference, -3%; 1-sided 95% CI, -10% to ∞; P = .004 for noninferiority). Pain scores were lower among patients in the 12F chest tube group (n = 54) vs the 24F group (n = 56) (mean VAS score, 22.0 mm vs 26.8 mm; adjusted difference, -6.0 mm; 95% CI, -11.7 to -0.2 mm; P = .04) and 12F chest tubes vs 24F chest tubes were associated with higher pleurodesis failure (30% vs 24%), failing to meet noninferiority criteria (difference, -6%; 1-sided 95% CI, -20% to ∞; P = .14 for noninferiority). Complications during chest tube insertion occurred more commonly with 12F tubes (14% vs 24%; odds ratio, 1.91; P = .20). CONCLUSIONS AND RELEVANCE Use of NSAIDs vs opiates resulted in no significant difference in pain scores but was associated with more rescue medication. NSAID use resulted in noninferior rates of pleurodesis efficacy at 3 months. Placement of 12F chest tubes vs 24F chest tubes was associated with a statistically significant but clinically modest reduction in pain but failed to meet noninferiority criteria for pleurodesis efficacy. TRIAL REGISTRATION isrctn.org Identifier: ISRCTN33288337.

Zoledronic Acid Is Effective against Experimental Malignant Pleural Effusion

RATIONALE Aminobiphosphonates, such as zoledronic acid (ZA), exert potent indirect antitumor effects and are currently being tested against human solid tumors. The antitumor actions of aminobiphosphonates, including angiostasis, are relevant to the pathogenesis of malignant pleural effusion (MPE), but no study has addressed the efficacy of these compounds against malignant pleural disease. OBJECTIVES Here we hypothesized that treatment of immunocompetent mice with ZA would halt tumor progression in a mouse model of adenocarcinoma-induced MPE. METHODS To induce MPE in mice, Lewis lung carcinoma cells were delivered directly into the pleural space. Subsequently, animals were treated with ZA in both a prevention and a regression protocol. MEASUREMENTS AND MAIN RESULTS ZA treatment resulted in significant reductions in pleural fluid accumulation and tumor dissemination, while it significantly prolonged survival. These effects of ZA were linked to enhanced apoptosis of pleural tumor cells, decreased formation of new vessels in pleural tumors, and reduced pleural vascular permeability. In addition, ZA was able to inhibit the recruitment of mononuclear cells to pleural tumors, with concomitant reductions in matrix metalloproteinase-9 release into the pleural space. Finally, ZA limited the expression of proinflammatory and angiogenic mediators, as well as the activity of small GTP proteins Ras and RhoA, in tumor cells in vivo and in vitro. CONCLUSIONS ZA is effective against experimental MPE, suggesting that this intervention should be considered for testing in clinical trials.

Static and dynamic mechanics of the murine lung after intratracheal bleomycin

BackgroundDespite its widespread use in pulmonary fibrosis research, the bleomycin mouse model has not been thoroughly validated from a pulmonary functional standpoint using new technologies. Purpose of this study was to systematically assess the functional alterations induced in murine lungs by fibrogenic agent bleomycin and to compare the forced oscillation technique with quasi-static pressure-volume curves in mice following bleomycin exposure.MethodsSingle intratracheal injections of saline (50 μL) or bleomycin (2 mg/Kg in 50 μL saline) were administered to C57BL/6 (n = 40) and Balb/c (n = 32) mice. Injury/fibrosis score, tissue volume density (TVD), collagen content, airway resistance (RN ), tissue damping (G) and elastance coefficient (H), hysteresivity (η), and area of pressure-volume curve (PV-A) were determined after 7 and 21 days (inflammation and fibrosis stage, respectively). Statistical hypothesis testing was performed using one-way ANOVA with LSD post hoc tests.ResultsBoth C57BL/6 and Balb/c mice developed weight loss and lung inflammation after bleomycin. However, only C57BL/6 mice displayed cachexia and fibrosis, evidenced by increased fibrosis score, TVD, and collagen. At day 7, PV-A increased significantly and G and H non-significantly in bleomycin-exposed C57BL/6 mice compared to saline controls and further increase in all parameters was documented at day 21. G and H, but not PV-A, correlated well with the presence of fibrosis based on histology, TVD and collagen. In Balb/c mice, no change in collagen content, histology score, TVD, H and G was noted following bleomycin exposure, yet PV-A increased significantly compared to saline controls.ConclusionsLung dysfunction in the bleomycin model is more pronounced during the fibrosis stage rather than the inflammation stage. Forced oscillation mechanics are accurate indicators of experimental bleomycin-induced lung fibrosis. Quasi-static PV-curves may be more sensitive than forced oscillations at detecting inflammation and fibrosis.

Mast cells mediate malignant pleural effusion formation

Mast cells (MCs) have been identified in various tumors; however, the role of these cells in tumorigenesis remains controversial. Here, we quantified MCs in human and murine malignant pleural effusions (MPEs) and evaluated the fate and function of these cells in MPE development. Evaluation of murine MPE-competent lung and colon adenocarcinomas revealed that these tumors actively attract and subsequently degranulate MCs in the pleural space by elaborating CCL2 and osteopontin. MCs were required for effusion development, as MPEs did not form in mice lacking MCs, and pleural infusion of MCs with MPE-incompetent cells promoted MPE formation. Once homed to the pleural space, MCs released tryptase AB1 and IL-1β, which in turn induced pleural vasculature leakiness and triggered NF-κB activation in pleural tumor cells, thereby fostering pleural fluid accumulation and tumor growth. Evaluation of human effusions revealed that MCs are elevated in MPEs compared with benign effusions. Moreover, MC abundance correlated with MPE formation in a human cancer cell-induced effusion model. Treatment of mice with the c-KIT inhibitor imatinib mesylate limited effusion precipitation by mouse and human adenocarcinoma cells. Together, the results of this study indicate that MCs are required for MPE formation and suggest that MC-dependent effusion formation is therapeutically addressable.

Protective Effects of Mastic Oil From Pistacia Lentiscus Variation Chia Against Experimental Growth of Lewis Lung Carcinoma

Mastic oil from Pistacia lentiscus variation chia, a traditionally used dietary flavoring agent with medicinal properties, has been shown to exert in vitro antitumor activities, but no study has addressed in vivo efficacy and mechanisms of action. Presently, we demonstrated that treatment of immunocompetent mice with mastic oil (45 mg/kg body weight, intraperitoneally, 3 times a wk for ∼3 wk) significantly inhibited tumor growth (56.4% ± 5.7 maximum reduction in tumor volumes) without toxicity. Analysis of tumors by immunohistochemistry and ELISA indicated that this effect is associated with increased apoptosis, reduced neovascularization, and inhibition of chemokine expression. Likewise mastic oil reduced vascular endothelial growth factor and chemokine release by Lewis lung carcinoma (LLC) cells. Furthermore, mastic oil administration decreased small guanosine triphosphatases (GTPases) Ras, RhoA and nuclear factor-κ-B-dependent reporter gene expression in vivo and in vitro, indicating a mechanistic link between mastic oil activities and blocking of relevant signaling and transcription pathways. A dose-response comparison with perillyl alcohol and α-pinene, two of its components, revealed a higher efficacy of mastic oil, pointing to a beneficial collective interaction among its ingredients. Conclusively, our results provide novel in vivo evidence of mastic oil inhibitory effects on tumor growth and set a rational basis for its future application in cancer prevention.

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

Malignant pleural mesothelioma is an aggressive malignancy of the pleural surface, predominantly caused by prior asbestos exposure. There is a global epidemic of malignant pleural mesothelioma underway, and incidence rates are predicted to peak in the next few years. This article summarises the epidemiology and pathogenesis of malignant pleural mesothelioma, before describing some key factors in the patient experience and outlining common symptoms. Diagnostic approaches are reviewed, including imaging techniques and the role of various biomarkers. Treatment options are summarised, including the importance of palliative care and methods of controlling pleural effusions. The evidence for chemotherapy, radiotherapy and surgery is reviewed, both in the palliative setting and in the context of trimodality treatment. An algorithm for managing malignant pleural effusion in malignant pleural mesothelioma patients is presented. Finally new treatment developments and novel therapeutic approaches are summarised. This article on mesothelioma describes pathogenesis, symptoms, diagnostic approaches and treatment options http://ow.ly/cjkb305aQGz

Specific effects of bortezomib against experimental malignant pleural effusion: a preclinical study.

BackgroundWe have previously shown that nuclear factor (NF)-κ B activation of mouse Lewis lung carcinoma (LLC) specifically promotes the induction of malignant pleural effusions (MPE) by these cells. In the present studies we hypothesized that treatment of immunocompetent mice with bortezomib tailored to inhibit cancer cell NF-κ B activation and not proliferation specifically inhibits MPE formation by LLC cells.ResultsTreatment of LLC cells with low concentrations of bortezomib (100 ng/ml) inhibited NF-κ B activation and NF-κ B-dependent transcription, but not cellular proliferation. Bortezomib treatment of immunocompetent C57BL/6 mice bearing LLC-induced subcutaneous tumors and MPEs significantly blocked tumor-specific NF-κ B activation. However, bortezomib treatment did not impair subcutaneous LLC tumor growth, but was effective in limiting LLC-induced MPE. This specific effect was evidenced by significant reductions in effusion accumulation and the associated mortality and was observed with both preventive (beginning before MPE formation) and therapeutic (beginning after MPE establishment) bortezomib treatment. The favorable impact of bortezomib on MPE was associated with suppression of cardinal MPE-associated phenomena, such as inflammation, vascular hyperpermeability, and angiogenesis. In this regard, therapeutic bortezomib treatment had identical favorable results on MPE compared with preventive treatment, indicating that the drug specifically counteracts effusion formation.ConclusionsThese studies indicate that proteasome inhibition tailored to block NF-κ B activation of lung adenocarcinoma specifically targets the effusion-inducing phenotype of this tumor. Although the drug has limited activity against advanced solid lung cancer, it may prove beneficial for patients with MPE.

Malignant pleural effusion: from bench to bedside

Malignant pleural effusion (MPE) is a common but serious condition that is related with poor quality of life, morbidity and mortality. Its incidence and associated healthcare costs are rising and its management remains palliative, with median survival ranging from 3 to 12 months. During the last decade there has been significant progress in unravelling the pathophysiology of MPE, as well as its diagnostics, imaging, and management. Nowadays, formerly bed-ridden patients are genotyped, phenotyped, and treated on an ambulatory basis. This article attempts to provide a comprehensive overview of current advances in MPE from bench to bedside. In addition, it highlights unanswered questions in current clinical practice and suggests future directions for basic and clinical research in the field. This review provides up to date knowledge for malignant pleural effusion covering aspects from bench to bedside http://ow.ly/10w7vN