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Background: Malignant Pleural Mesothelioma (MPM) is an aggressive tumor arising from mesothelial cells lining the pleural cavities characterized by resistance to standard therapies. Most of the molecular steps responsible for pleural transformation remain unclear; however, several growth factor signaling cascades are known to be altered during MPM onset and progression. Transducers of these pathways, such as PIK3CA-mTOR-AKT, MAPK, and ezrin/radixin/moesin (ERM) could therefore be exploited as possible targets for pharmacological intervention. This study aimed to identify 'druggable' pathways in MPM and to formulate a targeted approach based on the use of commercially available molecules, such as the multikinase inhibitor sorafenib and the mTOR inhibitor everolimus. Methods: We planned a triple approach based on: i) analysis of immunophenotypes and mutational profiles in a cohort of thoracoscopic MPM samples, ii) in vitro pharmacological assays, ii) in vivo therapeutic approaches on MPM xenografts. No mutations were found in 'hot spot' regions of the mTOR upstream genes (e.g. EGFR, KRAS and PIK3CA). Results: Phosphorylated mTOR and ERM were specifically overexpressed in the analyzed MPM samples. Sorafenib and everolimus combination was effective in mTOR and ERM blockade; exerted synergistic effects on the inhibition of MPM cell proliferation; triggered ROS production and consequent AMPK-p38 mediated-apoptosis. The antitumor activity was displayed when orally administered to MPM-bearing NOD/SCID mice. Conclusions: ERM and mTOR pathways are activated in MPM and 'druggable'by a combination of sorafenib and everolimus. Combination therapy is a promising therapeutic strategy against MPM. [ABSTRACT FROM AUTHOR]

Purpose: Knowledge of tumor mutational status has become a priority for effective NSCLC-tailored treatment. NSCLC diagnosis is more often reached through biopsy; thus, there is a clear need to implement for routine tumor molecular profiling on small cytological samples. This work aims to screen and compare the EGFR and KRAS mutational prevalence in fresh tumor cells and in corresponding routinely processed samples derived from trans-thoracic fine-needle aspiration. The latter currently represents the most appropriate diagnostic procedure in case of peripheral lesions, such as adenocarcinomas, which account for almost 40 % of all NSCLCs and for the highest EGFR mutational rates. Methods: Two hundred and forty-four patients carrying peripheral lung masses underwent CT-guided aspiration. The obtained material was split, and a part was addressed to conventional histopathological analysis while the remaining one was stored at −20 °C. In case of confirmation of adenocarcinoma, tumor genomic DNA was extracted from both fresh and fixed material, and EGFR and KRAS sequencing was performed. Results: We identified 136 adenocarcinomas; from 134, we could recover enough material for the study. A full match was demonstrated between EGFR/KRAS mutational prevalences through the two approaches tested. We found EGFR mutations in 13 patients (9.7 %); 7 were females and 11 never or former smokers. KRAS mutations occurred in 20 (14.9 %) patients. EGFR and KRAS mutations were mutually exclusive. Conclusions: Mutational screening on fresh cancer cells is an achievable, safe and cost-effective procedure which might allow routinely tumor molecular profiling as powerful integration of conventional histopathological analysis. [ABSTRACT FROM AUTHOR]

Caveolae are non-clathrin invaginations of the plasma membrane in most cell types; they are involved in signalling functions and molecule trafficking, thus modulating several biological functions, including cell growth, apoptosis and angiogenesis. The major structural protein in caveolae is caveolin-1, which is known to act as a key regulator in cancer onset and progression through its role as a tumour suppressor. Caveolin-1 can also promote cell proliferation, survival and metastasis as well as chemo- and radioresistance. Here, we discuss recent findings and novel concepts that support a role for caveolin-1 in cancer development and its distant spreading. We also address the potential application of caveolin-1 in tumour therapy and diagnosis. [ABSTRACT FROM AUTHOR]

Cancer of unknown primary origin (CUP) defines metastatic disease of unknown origin, accounting for 3-5% of all cancers. Growing evidence demonstrates that inappropriate execution of a genetic program named 'invasive growth,' driven by the MET oncogene, is implicated in the metastatic process. MET activation in cancers is mainly consequent to overexpression, whereas mutations are rarely found. We reasoned that the occurrence of MET somatic mutations might sustain premature occult dissemination of cancer cells, such as that observed in CUPs. We sequenced MET in genomic DNA obtained from 47 early metastatic cancers. By extensive immunohistochemical analysis a primary site was afterward postulated in 24 patients, whereas 23 cases remained of unknown primary (CUPs). MET somatic mutations were found in seven cases, all belonging to the CUP cohort. Mutational incidence (30%) was thus significantly higher than the expected one (4%), in the absence of high mutational background. Several nucleotide changes were novel and clustered either in the kinase domain or in the extracellular semaphorin domain. Mutated receptors were functional and sustained the transformed phenotype, suggesting that MET activating mutations are genetic markers associated with the CUP syndrome. Hum Mutat 31:1-7, 2010. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Background: Pulmonary alveolar proteinosis (PAP) is a rare disease characterised by accumulation of lipoproteinaceous material within alveoli, occurring in three clinically distinct forms: congenital, acquired and secondary. Among the latter, lysinuric protein intolerance (LPI) is a rare genetic disorder caused by defective transport of cationic amino acids. Whole Lung Lavage (WLL) is currently the gold standard therapy for severe cases of PAP. Case presentation: We describe the case of an Italian boy affected by LPI who, by the age of 10, developed digital clubbing and, by the age of 16, a mild restrictive functional impairment associated with a high-resolution computed tomography (HRCT) pattern consistent with pulmonary alveolar proteinosis. After careful assessment, he underwent WLL. Conclusion: Two years after WLL, the patient has no clinical, radiological or functional evidence of pulmonary disease recurrence, thus suggesting that WLL may be helpful in the treatment of PAP secondary to LPI. [ABSTRACT FROM AUTHOR]

Background: α1-antitrypsin and surfactant protein-A (SP-A) are major lung defense proteins. With the hypothesis that SP-A could bind α1-antitrypsin, we designed a series of in vitro experiments aimed at investigating the nature and consequences of such an interaction. Methods and results: At an α1-antitrypsin:SP-A molar ratio of 1:1, the interaction resulted in a calcium-dependent decrease of 84.6% in the association rate constant of α1-antitrypsin for neutrophil elastase. The findings were similar when SP-A was coupled with the Z variant of α1-antitrypsin. The carbohydrate recognition domain of SP-A appeared to be a major determinant of the interaction, by recognizing α1-antitrypsin carbohydrate chains. However, binding of SP-A carbohydrate chains to the α1-antitrypsin amino acid backbone and interaction between carbohydrates of both proteins are also possible. Gel filtration chromatography and turnover per inactivation experiments indicated that one part of SP-A binds several molar parts of α1-antitrypsin. Conclusion: We conclude that the binding of SP-A to α1-antitrypsin results in a decrease of the inhibition of neutrophil elastase. This interaction could have potential implications in the physiologic regulation of α1-antitrypsin activity, in the pathogenesis of pulmonary emphysema, and in the defense against infectious agents. [ABSTRACT FROM AUTHOR]

Objectives: A combination of functional measurements reflecting a decrease in maximum flow, a degree of lung hyperinflation, the relationship between maximum inspiratory and expiratory flows, bronchodilator response, and diffusing capacity of the lung for carbon monoxide (DLCO) was used to quantify the extent of emphysema, as assessed by high-resolution CT (HRCT) scanning.Design: Forced inspiratory and expiratory spirometry, lung volumes, reversibility test, and single-breath diffusing capacity were assessed before and after inhaling albuterol, 200 microg. Relationships between lung function variables and emphysema extent, as determined by HRCT scanning, were tested by univariate and multivariate analyses.Subjects: Thirty-nine COPD outpatients with moderate-to-severe obstruction.Measurements and Results: Emphysema extent, as assessed by HRCT scanning, ranged from 18 to 70%. All of the lung function parameters that were studied, except for the change in FEV1 percent predicted after salbutamol inhalation, correlated significantly with the extent of emphysema (r2 range, 0.19 to 0.44). Functional residual capacity, forced expiratory flow at 50% of FVC/forced inspiratory flow at 50% of FVC, DLCO/alveolar volume ratio, and bronchodilator-induced change in FEV1/FVC ratio were the only variables retained by stepwise multiple regression analysis. The multiple regression model explained 71% of the variability of emphysema extent measured by HRCT scanning.Conclusions: The combination of lung function measurements reflecting lung hyperinflation, bronchial collapsibility, lung diffusing capacity, and bronchodilator response provides a good estimate of the extent of emphysema, as evaluated by HRCT scanning. These data suggest that pulmonary function tests are useful in assessing and monitoring parenchymal damage in COPD patients. [ABSTRACT FROM AUTHOR]

Objectives: A combination of functional measurements reflecting a decrease in maximum flow, a degree of lung hyperinflation, the relationship between maximum inspiratory and expiratory flows, bronchodilator response, and diffusing capacity of the lung for carbon monoxide (DLCO) was used to quantify the extent of emphysema, as assessed by high-resolution CT (HRCT) scanning. Design: Forced inspiratory and expiratory spirometry, lung volumes, reversibility test, and single-breath diffusing capacity were assessed before and after inhaling albuterol, 200 µg. Relationships between lung function variables and emphysema extent, as determined by HRCT scanning, were tested by univariate and multivariate analyses. Subjects: Thirty-nine COPD outpatients with moderate-to-severe obstruction. Measurements and results: Emphysema extent, as assessed by HRCT scanning, ranged from 18 to 70%. All of the lung function parameters that were studied, except for the change in FEV1 percent predicted after salbutamol inhalation, correlated significantly with the extent of emphysema (r² range, 0.19 to 0.44). Functional residual capacity, forced expiratory flow at 50% of FVC/forced inspiratory flow at 50% of FVC, DLCO/alveolar volume ratio, and bronchodilator-induced change in FEV1/FVC ratio were the only variables retained by stepwise multiple regression analysis. The multiple regression model explained 71% of the variability of emphysema extent measured by HRCT scanning. Conclusions: The combination of lung function measurements reflecting lung hyperinflation, bronchial collapsibility, lung diffusing capacity, and bronchodilator response provides a good estimate of the extent of emphysema, as evaluated by HRCT scanning. These data suggest that pulmonary function tests are useful in assessing and monitoring parenchymal damage in COPD patients. [ABSTRACT FROM AUTHOR]

A multicentre trial was carried out to compare the efficacy and safety of dirithromycin with miocamycin in the treatment of patients with acute bronchitis or acute exacerbations of chronic bronchitis. The study was a single-blind, randomized, parallel-group study. Dirithromycin was administered orally at a dosage of 500 mg once daily and miocamycin was administered orally at a dosage of 600 mg twice daily; the duration of therapy was five to seven days for both drugs. The results, in 161 assessable patients (78 taking dirithromycin; 83 taking miocamycin), show that dirithromycin and miocamycin have comparable efficacy and safety in the treatment of bronchitis caused by susceptible bacterial pathogens. [ABSTRACT FROM PUBLISHER]

Background: Mediators released by alveolar macrophages, as well as by T cells, play an important part in modulating local immune processes in sarcoidosis. Among alveolar macrophage secretory products, arachidonic acid metabolites are known to regulate inflammatory and immune reactions. It has been suggested that cyclo-oxygenase and lipoxygenase pathway metabolites of arachidonic acid modulate the evolution of the granulomatous inflammatory response in the lung differently.Methods: Alveolar macrophages recovered from the bronchoalveolar lavage (BAL) fluid of 32 patients with sarcoidosis in different states of disease activity and 10 normal subjects were evaluated for their ability to release prostaglandin E2 (PGE2) and leukotriene B4 (LTB4). Alveolar macrophages were cultured in the presence or absence of opsonised zymosan (500 micrograms/ml), and PGE2 and LTB4 levels in the culture supernatants were determined by enzyme immunoassay (EIA).Results: Stimulated alveolar macrophages from patients with active sarcoidosis released higher LTB4 levels than those from normal subjects, but no differences in PGE2 release were observed between the two groups. The time course of LTB4 release by activated alveolar macrophages showed that normal cells produced similar levels of the hydroxyacid during the early and late times of culture while LTB4 release by activated cells from patients with sarcoidosis increased markedly after 60 minutes of culture, remaining elevated until 24 hours. Indomethacin (3 x 10(6) M) caused the expected inhibition of PGE2 formation without affecting LTB4 release.Conclusions: These results suggest that alveolar macrophages from the BAL fluid of patients with active sarcoidosis are primed to release LTB4, which may contribute to the locally heightened immune response. [ABSTRACT FROM AUTHOR]