Charalampos Moschos

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]

Effectiveness and safety of meropenem/ clavulanate-containing regimens in the treatment of MDR- and XDR-TB

No large study has ever evaluated the efficacy, safety and tolerability of meropenem/clavulanate to treat multidrug- and extensively drug-resistant tuberculosis (MDR- and XDR-TB). The aim of this observational study was to evaluate the therapeutic contribution, effectiveness, safety and tolerability profile of meropenem/clavulanate added to a background regimen when treating MDR- and XDR-TB cases. Patients treated with a meropenem/clavulanate-containing regimen (n=96) showed a greater drug resistance profile than those exposed to a meropenem/clavulanate-sparing regimen (n=168): in the former group XDR-TB was more frequent (49% versus 6.0%, p<0.0001) and the median (interquartile range (IQR)) number of antibiotic resistances was higher (8 (6–9) versus 5 (4–6)). Patients were treated with a meropenem/clavulanate-containing regimen for a median (IQR) of 85 (49–156) days. No statistically significant differences were observed in the overall MDR-TB cohort and in the subgroups with and without the XDR-TB patients; in particular, sputum smear and culture conversion rates were similar in XDR-TB patients exposed to meropenem/clavulanate-containing regimens (88.0% versus 100.0%, p=1.00 and 88.0% versus 100.0%, p=1.00, respectively). Only six cases reported adverse events attributable to meropenem/clavulanate (four of them then restarting treatment). The nondifferent outcomes and bacteriological conversion rate observed in cases who were more severe than controls might imply that meropenem/clavulanate could be active in treating MDR- and XDR-TB cases. Meropenem/clavulanate is effective and safe to treat MDR- and XDR-TB in comparison with controls http://ow.ly/XG75j

Comparison of effectiveness and safety of imipenem/clavulanate- versus meropenem/clavulanate-containing regimens in the treatment of MDR- and XDR-TB

No large study to date has ever evaluated the effectiveness, safety and tolerability of imipenem/clavulanate versus meropenem/clavulanate to treat multidrug- and extensively drug-resistant tuberculosis (MDR- and XDR-TB). The aim of this observational study was to compare the therapeutic contribution of imipenem/clavulanate versus meropenem/clavulanate added to background regimens to treat MDR- and XDR-TB cases. 84 patients treated with imipenem/clavulanate-containing regimens showed a similar median number of antibiotic resistances (8 versus 8) but more fluoroquinolone resistance (79.0% versus 48.9%, p<0.0001) and higher XDR-TB prevalence (67.9% versus 49.0%, p=0.01) in comparison with 96 patients exposed to meropenem/clavulanate-containing regimens. Patients were treated with imipenem/clavulanate- and meropenem/clavulanate-containing regimens for a median (interquartile range) of 187 (60–428) versus 85 (49–156) days, respectively. Statistically significant differences were observed on sputum smear and culture conversion rates (79.7% versus 94.8%, p=0.02 and 71.9% versus 94.8%, p<0.0001, respectively) and on success rates (59.7% versus 77.5%, p=0.03). Adverse events to imipenem/clavulanate and meropenem/clavulanate were reported in 5.4% and 6.5% of cases only. Our study suggests that meropenem/clavulanate is more effective than imipenem/clavulanate in treating MDR/XDR-TB patients. Meropenem/clavulanate is safe and more effective than imipenem/clavulanate in treating MDR and XDR-TB patients http://ow.ly/Z4S2o

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.

Effectiveness and Safety of Imipenem-Clavulanate Added to an Optimized Background Regimen (OBR) Versus OBR Control Regimens in the Treatment of Multidrug-Resistant and Extensively Drug-Resistant Tuberculosis

Simon Tiberi, Giovanni Sotgiu, Lia D’Ambrosio, Rosella Centis, Marcos Abdo Arbex, Edith Alarcon Arrascue, Jan Willem Alffenaar, Jose A. Caminero, Mina Gaga, Gina Gualano, Alena Skrahina, Ivan Solovic, Giorgia Sulis, Marina Tadolini, Valentina Alarcon Guizado, Saverio De Lorenzo, Aurora Jazmin Roby Arias, Anna Scardigli, Onno W. Akkerman, Alena Aleksa, Janina Artsukevich, Vera Avchinko, Eduardo Henrique Bonini, Felix Antonio Chong Marin, Lorena Collahuazo Lopez, Gerard de Vries, Simone Dore, Heinke Kunst, Alberto Matteelli, Charalampos Moschos, Fabrizio Palmieri, Apostolos Papavasileiou, Marie-Christine Payen, Andrea Piana, Antonio Spanevello, Dante Vargas Vasquez, Pietro Viggiani, Veronica White, Alimuddin Zumla and Giovanni Battista Migliori

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.

Secreted phosphoprotein-1 directly provokes vascular leakage to foster malignant pleural effusion

Secreted phosphoprotein-1 (SPP1) promotes cancer cell survival and regulates tumor-associated angiogenesis and inflammation, both central to the pathogenesis of malignant pleural effusion (MPE). Here, we examined the impact of tumor- and host-derived SPP1 in MPE formation and explored the mechanisms by which the cytokine exerts its effects. We used a syngeneic murine model of lung adenocarcinoma-induced MPE. To dissect the effects of tumor- versus host-derived SPP1, we intrapleurally injected wild-type and SPP1-knockout C57/BL/6 mice with either wild-type or SPP1-deficient syngeneic lung cancer cells. We demonstrated that both tumor- and host-derived SPP1 promoted pleural fluid accumulation and tumor dissemination in a synergistic manner (P<0.001). SPP1 of host origin elicited macrophage recruitment into the cancer-affected pleural cavity and boosted tumor angiogenesis, whereas tumor-derived SPP1 curtailed cancer cell apoptosis in vivo. Moreover, the cytokine directly promoted vascular hyper-permeability independently of vascular endothelial growth factor. In addition, SPP1 of tumor and host origin differentially affected the expression of proinflammatory and angiogenic mediators in the tumor microenvironment. These results suggest that SPP1 of tumor and host origin impact distinct aspects of MPE pathobiology to synergistically promote pleural fluid formation and pleural tumor progression. SPP1 may present an attractive target of therapeutic interventions for patients with MPE.

Osteopontin is upregulated in malignant and inflammatory pleural effusions.

Background and objective:  Osteopontin (OPN) is an important mediator of inflammation and cancer progression. In the present study, we asked whether pleural fluid (PF) and serum OPN concentrations differed between patients with pleural effusions of different aetiologies, and whether assessment of OPN levels was useful for diagnostic purposes.