Serafino A. Marsico

Alpha‐interferon and its effects on signal transduction pathways

Interferon‐α (IFNα) is a recombinant protein widely used in the therapy of several neoplasms such as myeloma, renal cell carcinoma, epidermoid cervical and head and neck tumors, and melanoma. IFNα, the first cytokine to be produced by recombinant DNA technology, has emerged as an important regulator of cancer cell growth and differentiation, affecting cellular communication and signal transduction pathways. However, the way by which tumor cell growth is directly suppressed by IFNα is not well known. Wide evidence exists on the possibility that cancer cells undergo apoptosis after the exposure to the cytokine. Here we will review the consolidate signal transducer and activator of transcription (STAT)‐dependent mechanism of action of IFNα. We will discuss data obtained by us and others on the triggering of the stress‐dependent kinase pathway induced by IFNα and its correlations with the apoptotic process. The regulation of the expression of proteins involved in apoptosis occurrence will be also described. In this regard, IFNα is emerging as a post‐translational controller of the intracellular levels of the apoptosis‐related protein tissue transglutaminase (tTG). This new way of regulation of tTG occurs through the modulation of their proteasome‐dependent degradation induced by the cytokine. Until today, inconsistent data have been obtained regarding the clinical effectiveness of IFNα in the therapy of solid tumors. In fact, the benefit of IFNα treatment is limited to some neoplasms while others are completely or partially resistant. The mechanisms of tumor resistance to IFNα have been studied in vitro. The alteration of JAK‐STAT components of the IFNα‐induced signaling, can be indeed a mechanism of resistance to IFN. However, we have recently described a reactive mechanism of protection of tumor cells from the apoptosis induced by IFNα dependent on the epidermal growth factor (EGF)‐mediated Ras/extracellular signal regulated kinase (Erk) signaling. The involvement of the Ras→Erk pathway in the protection of tumor cells from the apoptosis induced by IFNα is further demonstrated by both Ras inactivation by RASN17 transfection and mitogen extracellular signal regulated kinase 1 (Mek‐1) inhibition by exposure to PD098059. These data strongly suggest that the specific disruption of the latter could be a useful approach to potentiate the antitumour activity of IFNα against human tumors based on the new mechanistic insights achieved in the last years.

Metabonomic analysis of exhaled breath condensate in adults by nuclear magnetic resonance spectroscopy

Exhaled breath condensate (EBC) is a noninvasive method for the study of airway lining fluid. Nuclear magnetic resonance (NMR) spectroscopy can provide biochemical profiles of metabolites in biological samples. The aim of the present study was to validate the NMR metabonomic analysis of EBC in adults, assessing the role of pre-analytical variables (saliva and disinfectant contamination) and the potential clinical feasibility. In total, 36 paired EBC and saliva samples, obtained from healthy subjects, laryngectomised patients and chronic obstructive pulmonary disease patients, were analysed by means of 1H-NMR spectroscopy followed by principal component analysis. The effect on EBC of disinfectant, used for reusable parts of the condenser, was assessed after different washing procedures. To evaluate intra-day repeatability, eight subjects were asked to collect EBC and saliva twice within the same day. All NMR saliva spectra were significantly different from corresponding EBC samples. EBC taken from condensers washed with recommended procedures invariably showed spectra perturbed by disinfectant. Each EBC sample clustered with corresponding samples of the same group, while presenting intergroup qualitative and quantitative signal differences (94% of the total variance within the data). In conclusion, the nuclear magnetic resonance metabonomic approach could identify the metabolic fingerprint of exhaled breath condensate in different clinical sets of data. Moreover, metabonomics of exhaled breath condensate in adults can discriminate potential perturbations induced by pre-analytical variables.

Real-life prospective study on asthma control in Italy: Cross-sectional phase results

OBJECTIVES To estimate the prevalence of partly controlled and uncontrolled asthmatic patients, to evaluate quality of life and healthcare resource consumption. METHODS Cross-sectional phase followed by a 12-month prospective phase. Asthma Control Test and the EQ-5D were used. RESULTS 2853 adult patients recruited in 56 Hospital Respiratory Units in Italy were evaluated: 64.4% had controlled asthma, 15.8% partly controlled asthma and 19.8% were uncontrolled. The mean (SD) EQ-5D score was 0.86 (0.17) in controlled, 0.75 (0.20) in partly controlled and 0.69 (0.23) in uncontrolled patients (p<0.001 between groups). The number of patients requiring hospitalization or emergency room visits was lower in controlled (1.8% and 1.6%, respectively) than in partly controlled (5.1% and 11.5%) and uncontrolled (6.4% and 18.6%). A combination of an inhaled corticosteroid and a long-acting beta-2 agonist was the reported therapy by 56.0% of patients, with the rate of controlled asthma and improved quality of life being higher in patients on extrafine beclomethasone/formoterol compared to budesonide/formoterol (p<0.05) and fluticasone/salmeterol (p<0.05 for quality of life). CONCLUSIONS Asthma control is achieved in a good proportion of Italian patients. Differences may be detected in a real-life setting in favor of extrafine beclomethasone/formoterol combination.

Mitogen-activated protein kinases and asthma

Mitogen‐activated protein kinases (MAPKs) are evolutionary conserved enzymes which play a key role in signal transduction mediated by cytokines, growth factors, neurotransmitters and various types of environmental stresses. In the airways, these extracellular stimuli elicit complex inflammatory and structural changes leading to the typical features of asthma including T cell activation, eosinophil and mast cell infiltration, as well as bronchial hyperresponsiveness and airway remodelling. Because MAPKs represent an important point of convergence for several different signalling pathways, they affect multiple aspects of normal airway function and also significantly contribute to asthma pathophysiology. Therefore, this review focuses on the crucial involvement of MAPKs in asthma pathogenesis, thus also discussing their emerging role as molecular targets for anti‐asthma drugs.

Molecular mechanisms underlying airway smooth muscle contraction and proliferation: implications for asthma.

Airway smooth muscle (ASM) plays a key role in bronchomotor tone, as well as in structural remodeling of the bronchial wall. Therefore, ASM contraction and proliferation significantly participate in the development and progression of asthma. Many contractile agonists also behave as mitogenic stimuli, thus contributing to frame a hyperresponsive and hyperplastic ASM phenotype. In this review, the molecular mechanisms and signaling pathways involved in excitation-contraction coupling and ASM cell growth will be outlined. Indeed, the recent advances in understanding the basic aspects of ASM biology are disclosing important cellular targets, currently explored for the implementation of new, more effective anti-asthma therapies.

Potential role of potassium channel openers in the treatment of asthma and chronic obstructive pulmonary disease.

Airway smooth muscle (ASM) cells express various types of potassium (K+) channels which play a key role in determining the resting membrane potential, a relative electrical stability and the responsiveness to both contractile and relaxant agents. In addition, K+ channels are also involved in modulation of neurotransmitter release from airway nerves. The most important K+ channels identified in airways include large and small Ca2+-activated, delayed-rectifier, and ATP-sensitive channels. These K+ channels are structurally and functionally different, thus playing distinct roles in airway electrophysiology and pharmacology. Many in vitro and in vivo studies, performed in both animals and humans, have shown that K+ channel openers are able to induce hyperpolarization of ASM cells, bronchodilation, suppression of airway hyperresponsiveness (AHR), and inhibition of neural reflexes. Therefore, airway K+ channels represent a suitable pharmacological target for the development of new effective therapeutic options in the treatment of asthma and chronic obstructive pulmonary disease (COPD).

Endothelin-1 Induces Proliferation of Human Lung Fibroblasts and IL-11 Secretion Through an ET A Receptor-Dependent Activation of Map Kinases

Endothelin‐1 (ET‐1) is implicated in the fibrotic responses characterizing interstitial lung diseases, as well as in the airway remodeling process occurring in asthma. Within such a context, the aim of our study was to investigate, in primary cultures of normal human lung fibroblasts (NHLFs), the ET‐1 receptor subtypes, and the intracellular signal transduction pathways involved in the proliferative effects of this peptide. Therefore, cells were exposed to ET‐1 in the presence or absence of an overnight pre‐treatment with either ETA or ETB selective receptor antagonists. After cell lysis, immunoblotting was performed using monoclonal antibodies against the phosphorylated, active forms of mitogen‐activated protein kinases (MAPK). ET‐1 induced a significant increase in MAPK phosphorylation pattern, and also stimulated fibroblast proliferation and IL‐6/IL‐11 release into cell culture supernatants. All these effects were inhibited by the selective ETA antagonist BQ‐123, but not by the specific ETB antagonist BQ‐788. The stimulatory influence of ET‐1 on IL‐11, but not on IL‐6 secretion, was prevented by MAPK inhibitors. Therefore, such results suggest that in human lung fibroblasts ET‐1 exerts a profibrogenic action via an ETA receptor‐dependent, MAPK‐mediated induction of IL‐11 release and cell proliferation.

Respiratory infections and asthma

Summary Respiratory tract infections caused by both viruses and/or atypical bacteria are involved in the pathogenesis of asthma. In particular, several viruses such as respiratory syncytial virus, rhinovirus and influenza/parainfluenza viruses may favour the expression of the asthmatic phenotype, being also implicated in the induction of disease exacerbations. Within this pathological context, a significant role can also be played by airway bacterial colonizations and infections due to Chlamydiae and Mycoplasms. All these microbial agents probably interfere with complex immunological pathways, thus contributing to induce and exacerbate asthma in genetically predisposed individuals.

Update on optimal use of omalizumab in management of asthma

Omalizumab is a humanized monoclonal anti-IgE antibody recently approved for the treatment of severe allergic asthma. This drug inhibits allergic responses by binding to serum IgE, thus preventing interaction with cellular IgE receptors. Omalizumab is also capable of downregulating the expression of high affinity IgE receptors on inflammatory cells, as well as the numbers of eosinophils in both blood and induced sputum. The clinical effects of omalizumab include improvements in respiratory symptoms and quality of life, paralleled by a reduction of asthma exacerbations, emergency room visits, and use of systemic corticosteroids and rescue bronchodilators. Omalizumab is relatively well-tolerated, and only rarely induces anaphylactic reactions. Therefore, this drug represents a valid option as add-on therapy for patients with severe persistent allergic asthma inadequately controlled by high doses of standard inhaled treatments.

1-year prospective real life monitoring of asthma control and quality of life in Italy

ObjectivesThe study aimed at prospectively evaluating the evolution of asthma control in Italy, to evaluate the reasons for lack of asthma control, perceived quality of life (QoL) and association with level of asthma control, the impact of pharmacological treatment, the number of exacerbations and the healthcare resource consumption.MethodsPRISMA (PRospectIve Study on asthMA control) was an observational study performed in asthmatic patients including a cross-sectional phase and a 12-month prospective phase. Asthma control was assessed with the Asthma Control Test™ (ACT) and QoL was evaluated with EuroQoL-5D questionnaire filled in and collected during 5 clinic visits together with all the other data.ResultsThe prospective phase included 1017 patients with uncontrolled (55.7%) or partly controlled asthma (44.3%). Out of the 739 patients evaluable after 12 months, 22.2% achieved full asthma control (ACT score = 25) and 58.7% reached a good control (ACT score: 20–24). The improvement in asthma control was associated with improved QoL and reduced hospital visits. The main reasons for lack of asthma control were comorbidities, continued exposure to irritants/triggers and poor adherence to therapy. The frequency of exacerbations was lower in patients with controlled asthma.A fixed combination therapy with an inhaled corticosteroid and a long-acting β2 agonist was reported by 77.0% of patients. A better asthma control and improved QoL were achieved with extrafine beclomethasone/formoterol compared to either budesonide/formoterol or fluticasone/salmeterol.ConclusionsAn improvement in asthma control and QoL can be achieved during a 1-year monitoring in a real life setting. Extrafine beclomethasone/formoterol was associated with significant benefit in terms of asthma control and QoL compared to large-particles combinations.ClinicalTrials.gov number NCT01110460.