Molecular profiling of EGFR family in chronic obstructive pulmonary disease: correlation with airway obstruction.

BACKGROUND: Growth factors mediate various cellular responses to environmental stimuli. Specifically, exposure of lung epithelium to oxidative stress induced by cigarette smoke stimulates aberrant epidermal growth factor receptor (ERBB) family activation. This study's objective was to evaluate the expression of ERBB1-4 receptors in the lung tissue of smokers with or without chronic obstructive pulmonary disease (COPD). MATERIALS AND METHODS: ERBBs expression was measured by microarray analysis in lung tissue samples from five patients with COPD and five non-COPD smokers, and by quantitative real-time PCR in additional 20 patients with COPD (GOLD stage II), 15 non-COPD smokers and 10 nonsmoker controls. RESULTS: Microarray data analysis revealed that ERBB receptors expression was elevated in patients with COPD compared to non-COPD smokers, ranging from 1·62- to 2·45-fold, (P < 0·01). Real-time qPCR verified that patients with COPD had higher ERBB1-3 expression levels compared with non-COPD smokers (PERBB1  < 0·001; PERBB2  = 0·003; PERBB3  = 0·003) and nonsmokers (PERBB1  = 0·019; PERBB2  = 0·005; PERBB3  = 0·011). On the other hand, ERBB4 mRNA levels gradually increased from nonsmokers (0·74 ± 0·19) to non-COPD smokers (1·11 ± 0·05) to patients with COPD (1·57 ± 0·28) and were correlated with the degree of airflow obstruction (PFEV1  < 0·001). DISCUSSION: These data suggest that ERBB1-3 overexpression is not related only to smoking exposure but probably to epithelial remodelling and mucociliary system distortion, characterizing COPD. Additionally, the inverse correlation of ERBB4 with FEV1 exhibits a possible link between ERBB4 and COPD severity.

Granule cytotoxic activity and oxidative DNA damage in smoking and nonsmoking patients with asthma.

BACKGROUND: Lung cytotoxic mechanisms trigger the release of perforin and granzymes, causing oxidative DNA damage that ultimately leads to apoptosis. These effects, although demonstrated in COPD, have not been investigated in patients with asthma and in particular in patients with asthma who smoke. Our aim was to measure perforin, granzyme A, granzyme B, and 8-OHdG expression in sputum from smoking and nonsmoking patients with asthma, compared with smoking and nonsmoking control subjects. METHODS: Perforin, granzyme A, granzyme B, and 8-OHdG expression levels were detected by enzyme-linked immunosorbent assays in induced sputum specimens. RESULTS: Perforin expression was increased in 40% of smokers and 45% of smoking patients with asthma and in only 7% of nonsmoking patients with asthma (P = .004), compared with control subjects' values. In contrast, granzymes A and B levels were increased in > 40% of patients in all three groups vs control subjects. Finally, 8-OHdG levels were elevated in 35% of smoking patients with asthma, in 20% of smokers, and in only 10% of nonsmoking patients with asthma. Statistical analysis revealed a positive correlation between granzyme A (P < .001) and granzyme B (P = .006) expression levels and the number of pack-years in smoking patients with asthma. CONCLUSIONS: Asthma cytotoxic immune response is mainly represented by granzymes A and B, whereas in smoking patients with asthma perforin and 8-OHdG are additionally involved, resembling the immune response in COPD.

Immune and genetic mechanisms in COPD: possible targets for therapeutic interventions.

Genetic, immune and environmental interactions are key elements for the development of COPD. Cigarette smoking is considered the primary risk factor initiating inflammatory cascades in genetically susceptible individuals. The "danger signals" elicited by the injured cells of non-specific immunity induce the downstream activation of proinflammatory cascades and antigen-specific adaptive immune responses. The produced oxidative stress further damages the lung leading to acquired genetic changes (histone deacetylation, microsatellite DNA instability, DNA methylation, telomere shortening, miRNA alterations) due to an inefficient DNA repair machinery. On the other hand, augmented apoptosis, impaired efferocytosis and abnormal tissue remodeling contribute to the chronic inflammatory response and tissue destruction in COPD. This review focuses on the role of genetic, epigenetic and immune mechanisms in the development of COPD in order to put forward possible prognostic and therapeutic targets.

DNA damage due to oxidative stress in Chronic Obstructive Pulmonary Disease (COPD).

According to the American Thorasic Society (ATS)/European Respiratory Society (ERS) Statement, chronic obstructive pulmonary disease (COPD) is defined as a preventable and treatable disease with a strong genetic component, characterized by airflow limitation that is not fully reversible, but is usually progressive and associated with an enhanced inflammatory response of the lung to noxious particles or gases. The main features of COPD are chronic inflammation of the airways and progressive destruction of lung parenchyma and alveolar structure. The pathogenesis of COPD is complex due to the interactions of several mechanisms, such as inflammation, proteolytic/antiproteolytic imbalance, oxidative stress, DNA damage, apoptosis, enhanced senescence of the structural cells and defective repair processes. This review focuses on the effects of oxidative DNA damage and the consequent immune responses in COPD. In susceptible individuals, cigarette smoke injures the airway epithelium generating the release of endogenous intracellular molecules or danger-associated molecular patterns from stressed or dying cells. These signals are captured by antigen presenting cells and are transferred to the lymphoid tissue, generating an adaptive immune response and enhancing chronic inflammation.

Downregulation of lung mitochondrial prohibitin in COPD.

Prohibitins (PHB1 and PHB2) are versatile proteins located at the inner mitochondrial membrane, maintaining normal mitochondrial function and morphology. They interact with the NADH dehydrogenase protein complex, which is essential for oxidoreductase activity within cells. However, their expression in lung epithelium, especially in smokers and patients with inflammatory lung diseases associated with increased oxidative stress, such as COPD, is unknown. Lung tissue specimens from 45 male subjects were studied: 20 COPD patients [age: 65.7 ± 5.8 years, smoking: 84.6 ± 33.6 pack-years, FEV(1) (%pred.): 58.7 ± 14.6, FEV(1)/FVC (%): 63.8 ± 9.4], 15 non-COPD smokers [age: 59.0 ± 12.1 years, smoking: 52.5 ± 20.8 pack-years, FEV(1) (%pred.): 85.5 ± 14.2, FEV(1)/FVC (%): 78.5 ± 4.7] and 10 non-smokers. Quantitative real-time PCR experiments were carried out for PHB1 and PHB2, using ß-actin as internal control. Non-COPD smokers exhibited lower PHB1 mRNA levels when compared to non-smokers (0.55 ± 0.06 vs. 0.90 ± 0.06, P = 0.043), while PHB1 expression was even further decreased in COPD patients (0.32 ± 0.02), a statistically significant finding vs. both non-COPD smokers (P = 0.040) and non-smokers (P < 0.001). By contrast, PHB2 levels were similar among the three study groups. Western blot analysis for the PHB1 protein verified the qPCR results (non-smokers: 1.77 ± 0.13; non-COPD smokers: 0.97 ± 0.08; COPD patients: 0.59 ± 0.10, P = 0.007). Further analysis revealed that PHB1 downregulation in COPD patients cannot be attributed solely to smoking, and that PHB1 expression levels are associated with the degree of airway obstruction [FEV(1) (P(mRNA) = 0.004, P(protein) = 0.014)]. The significant downregulation of PHB1 in COPD and non-COPD smokers in comparison to non-smokers possibly reflects a distorted mitochondrial function due to decreased mitochondrial stability, especially in the mitochondria of COPD patients.

Oxidative DNA damage and somatic mutations: a link to the molecular pathogenesis of chronic inflammatory airway diseases.

BACKGROUND: Acquired somatic mutations induced by oxidative stress may contribute to the molecular pathogenesis of chronic inflammatory airway diseases. The objective of this study was to assess the intensity of oxidative DNA damage and the presence of microsatellite DNA instability (MSI), a marker of acquired somatic mutations, in patients with COPD, patients with noncystic fibrosis bronchiectasis, and control subjects. METHODS: Induced sputum and peripheral blood from 97 subjects were analyzed; 36 patients with COPD, 36 patients with bronchiectasis, 15 smokers without COPD, and 10 healthy control subjects. DNA was extracted and analyzed for MSI. 8-hydroxy-2'-deoxyguanosine (8-OHdG), a specific marker of oxidant-induced DNA damage, was measured in serum and sputum supernatants. RESULTS: None of the patients with bronchiectasis or control subjects (non-COPD smokers, healthy subjects) exhibited any genetic alteration. In contrast, MSI was found in 38% of COPD specimens. Sputum 8-OHdG was statistically significantly increased in COPD when compared with subjects with bronchiectasis (P = .0002), smokers without COPD (P = .0056), and healthy subjects (P = .0003). Sputum 8-OHdG in MSI-positive patients with COPD differed significantly from that of MSI-negative patients with COPD (P = .04) and smokers without COPD (P = .008), but was not statistically different (P = .07) among MSI-negative patients with COPD and smokers without COPD. Serum 8-OHdG was significantly increased in MSI-positive compared with MSI-negative patients with COPD (P = .001), but was not statistically significant in smokers without COPD (P = .09). Serum 8-OHdG was increased in smokers without COPD compared with MSI-negative patients with COPD (P = .009). CONCLUSIONS: There is a clear disparity in COPD regarding oxidant-induced DNA damage and somatic mutations. This may reflect a difference in the oxidative stress per se or a deficient antioxidant and/or repair capacity in the lungs of patients with COPD.

Lymphangiogenesis in COPD: another link in the pathogenesis of the disease.

BACKGROUND: New lymphatic vessels are associated with tissue injury and repair. Recent studies have shown increased lymphatic follicles formation in the lungs of COPD patients. We hypothesized that lymphatic vascular remodeling could be part of COPD pathogenesis. AIM: To investigate the lymphangiogenetic process in COPD we measured the lymphatic microvessel density (LMVD), the lymphatic invasion (L.I), and their correlation with clinical and laboratory parameters. METHODS: Lung tissue from 20 COPD patients and 20 non-COPD smokers was immunohistochemically stained for D2-40 (lymphatic endothelial cell marker), and LYVE-1 (lymphatic endothelial hyaluronan receptor 1). Both groups had similar age and smoking history. RESULTS: D2-40 and LYVE-1 were expressed in all specimens. Lymphatic invasion was presented only in COPD specimens. Lymphatic microvessel density (LMVD) as revealed by D2-40 and LYVE-1 markers was statistically significantly higher in COPD patients when compared with non-COPD smokers. Both markers (D2-40, LYVE-1) were correlated with FEV1 (% pred) (R(2) = 0.415, R(2) = 0.605, respectively). CONCLUSIONS: We report for the first time high lymphatic microvessel density and lymphatic invasion in COPD patients, related to the degree of airway obstruction. Our findings could provide novel insights in the pathogenesis of the disease.

Long-term omalizumab treatment in severe allergic asthma: the South-Eastern Mediterranean "real-life" experience.

BACKGROUND: Omalizumab is a recombinant humanized anti-IgE monoclonal antibody indicated as an add-on treatment for severe allergic asthma, inadequately controlled despite high dose of inhaled corticosteroids (ICS) and long-acting b2-agonists. OBJECTIVES: Medical registries were used to evaluate the 4 months, 1 and 4 years effectiveness of omalizumab treatment, in a non-interventional, observational "real-life" study. METHODS: Sixty patients with severe persistent allergic asthma from 5 South-Eastern Mediterranean centres from Crete and Cyprus were evaluated. Effectiveness outcomes included spirometry, severe asthma exacerbations rate, level of asthma control (ACT), and additional asthma medication (inhaled steroids). RESULTS: Outcome variables improved after 4 months and sustained after 1 and 4 years treatment with Omalizumab. FEV1 improved statistically significant at all time points versus baseline [ΔFEV1 (% pred.) = +21 p = 0.008 at 4 months, ΔFEV1 (% pred.) = +24.5 p < 0.0001 at 4 years after treatment]. Similarly, FVC increased statistically significant versus baseline [ΔFVC (% pred.) = +20 p = 0.002 at 4 months, ΔFVC (% pred.) = +22.6 p = 0.0002 at 4 years]. The level of asthma control as evaluated by ACT was significantly improved after treatment (+12% p = 0.001 at 4 months, +24% p < 0.0001 at 4 years). Omalizumab treatment reduced significantly asthma exacerbations rate (-65% p = 0.0002 at 1 year, and -70% p < 0.0001 at 4 years). The use of inhaled steroids decreased statistically significant after 4 months (p = 0.017), 1 year (p = 0.029) and 4 years (p = 0.014) of omalizumab treatment. CONCLUSIONS: This long-term "real-life" study demonstrated significant improvement in lung function and other clinical outcomes after omalizumab treatment, evident at 4 months, and sustained after 1 and 4 years suggesting its efficacy in severe allergic asthma, in the "real-life" practice.

Asthma in the Elderly: Can We Distinguish It from COPD?

Asthma in older adults affects quality of life and results in a higher hospitalization rate and mortality. In common clinical practice, asthma in the elderly is underdiagnosed and undertreated or overdiagnosed and mistreated. The age-related reduction in perception of shortness of breath and the high incidence of comorbidities make the diagnosis and management more difficult and challenging for the physicians. Chronic obstructive pulmonary disease (COPD) is usually easy to distinguish from asthma, but sometimes the distinction from late-onset asthma in older patients, particularly in cigarette smokers, is difficult and may be impossible. Both diseases are characterized by the presence of airflow obstruction but have distinct pathogenesis, inflammatory pattern, and prognosis. The distinction between Asthma and COPD based simply on spirometric parameters is difficult especially in the elderly asthmatics. The combination of lung function testing, bronchial hyperresponsiveness (BHR) and atopy status, HRCT scans, and the newly developed biological techniques, allowing the assessment of biomarker profiles, could facilitate the distinction between these diseases.

Deregulation of apoptosis mediators' p53 and bcl2 in lung tissue of COPD patients.

Abnormal apoptotic events in chronic obstructive pulmonary disease (COPD) subvert cellular homeostasis and may play a primary role in its pathogenesis. However, studies in human subjects are limited. p53 and bcl2 protein expression was measured by western blot on lung tissue specimens from 43 subjects (23 COPD smokers and 20 non-COPD smokers), using beta-actin as internal control. Additionally, p53 and bcl2 expression patterns were evaluated by immunohistochemistry in formalin-fixed, paraffin-embedded lung tissue sections from the same individuals. Western blot analysis showed statistically significant increased p53 protein levels in COPD smokers in comparison with non-COPD smokers (p = 0.038), while bcl2 protein levels were not statistically different between the two groups. Lung immunohistochemistry showed increased ratio of positive p53-stained type II pneumocytes/total type II pneumocytes in COPD smokers compared to non-COPD smokers (p = 0.01), whereas the p53 staining ratio in alveolar macrophages and in lymphocyte-like cells did not differ statistically between the two groups. On the other hand, bcl2 expression did not differ between the two groups in all three cell types. The increased expression of pro-apoptotic p53 in type II pneumocytes of COPD patients not counterbalanced by the anti-apoptotic bcl2 could reflect increased apoptosis in the alveolar epithelium of COPD patients. Our results confirm previous experiments and support the hypothesis of a disturbance in the balance between the pro- and anti-apoptotic mediators in COPD.

Altered surfactant protein-A expression in type II pneumocytes in COPD.

BACKGROUND: Pulmonary surfactant protein A (SP-A) is a lectin, with multiple functions that contribute to innate host defense and the regulation of the inflammatory process in the lung. In normal conditions, SP-A seems to protect against the effects of smoking. However, studies in smokers with or without COPD are limited. METHODS: Western blots on lung tissue specimens from 60 male subjects (32 patients with COPD, 18 smokers without COPD, and 10 control nonsmokers) for SP-A and the housekeeping protein actin were carried out. Additionally, the SP-A expression pattern was evaluated by immunohistochemistry in formalin-fixed, paraffin-embedded lung tissue sections from the same subjects. RESULTS: Western blots revealed significantly higher SP-A levels in control nonsmokers (4.8 +/- 0.05) when compared with patients with COPD (0.6 +/- 0.7) and smokers without COPD (2.4 +/- 0.9), (P < .05). However, differences that were not statistically significant were observed in SP-A levels among the patients with COPD and the smokers without COPD (P = .12). The immunohistochemical examinations showed an increase in the overall number of type II pneumocytes per high-power field in patients with COPD, but a decreased ratio of SP-A positive type II pneumocytes to total type II pneumocytes, compared with smokers without COPD (P = .001). This ratio was also correlated with FEV(1) (percent predicted [% pred]), (r = 0.490, P = .001). The overall number of alveolar macrophages per high-power field was significantly higher in patients with COPD compared with smokers without COPD (P = .001). The ratio of SP-A positive alveolar macrophages was increased in patients with COPD when compared with smokers without COPD (P = .002), while this was correlated with airway obstruction (FEV(1), % pred) (r = 0.281, P = .04). CONCLUSIONS: Our results indicate that altered SP-A expression could be another link to COPD pathogenesis and highlights the need for further studies on surfactant markers in COPD.

Somatic DNA alterations in lung epithelial barrier cells in COPD patients.

BACKGROUND: Instability of the Microsatellite DNA Instability (MSI) and Loss of Heterozygosity (LOH) have been previously detected in sputum cells of COPD patients. However, the particular cell subpopulation exhibiting genetic instability in COPD was uncertain. The aim of this study was to determine which cell type expresses Microsatellite DNA Instability in sputum and BALF samples from COPD patients. METHODS: Thirty-five COPD patients and 30 non-COPD smokers were studied. Sputum was induced from 20 COPD patients and 20 non-COPD smokers and BALF was obtained from 15 COPD patients and 10 non-COPD smokers. The sputum cell pellet and BALF samples were processed using immunomagnetic technology to separate antibody-specific cell subpopulations, using CD45+ for leukocytes, Epithelial enrich (MACS) for sputum epithelial cells and HEA-human epithelial antigen-(Dynal) for BAL epithelial cells. Microsatellite DNA amplification was performed using specific primers, namely G29802, D6S2223, D6S344, D6S263, D5S207, D13S71, RH70958, and D17S250. The presence of MSI and/or LOH was analyzed with LI-COR Saga GT Microsatellite Analysis Software. MEASUREMENTS AND MAIN RESULTS: None of the non-COPD smokers exhibited any genetic alteration. MSI and LOH were found in 15 cases (8 MSI and 7 LOH) in sputum and BAL samples. MSI and/or LOH were revealed only in the epithelial barrier cells. LOH was detected in D5S207, D6S344, G29802 and D17S250 microsatellite markers, while MSI in D13S71, D5S207 and D6S344. The entire leukocyte subpopulation exhibited no genetic alteration. CONCLUSIONS: Our results support the hypothesis that chronic inflammation and oxidative burden in COPD can lead to DNA damage of the lung epithelial barrier cells, detected at the Microsatellite DNA level. Further studies are required to investigate the significance of these findings in the pathogenesis of COPD.

Acquired somatic mutations in the microsatellite DNA, in children with bronchial asthma.

OBJECTIVES: High incidence of genetic alterations at the microsatellite (MS) DNA level has been reported in asthmatic adults. WORKING HYPOTHESIS: The aim of this study was to investigate whether microsatellite instability (MSI) and loss of heterozygosity (LOH) were detectable phenomena in children with asthma. METHODOLOGY: DNA was extracted from sputum and blood cells of 27 children (10.8 +/- 2.5 years) with mild to moderate asthma, and from 8 healthy, never-smoked young adults. Fourteen polymorphic MS markers, namely D5S207, D5S820, D5S637, D6S344, D6S2223, D6S263, SGC35231, D11S1253, D11S1337, D11S97, USAT24G1, D13S273, D14S258, and D14S292, located on chromosomes (chr) 5q, 6p, 11q, 13q, and 14q were used to assess MSI and LOH. RESULTS: None of the healthy subjects exhibited any genetic alteration. Five out of 27 children (18.5%) exhibited MSI or LOH in sputum cells versus blood samples from which 3 in the marker USAT24G1 (chr 13q14.1), 1 in the marker D14S258 (chr 14q23-q24.3), and 1 in the marker D5S637 (chr 5q12-q13). Compared to a previous study, with asthmatic adults, whereas MSI and/or LOH was exhibited in approximately 60% of the cases, the current study reported <20% of genetic alterations, at the MS DNA, in asthmatic children. CONCLUSIONS: Our results showed that genetic instability in the MS DNA, is present in asthmatic children, but to less extent than in adult asthmatics from previous studies. These findings may support the hypothesis that somatic mutations may be early acquired in the natural course of asthma and could represent another contributor to the molecular pathogenesis of the disease. However, further studies are needed to clarify this hypothesis.

Different angiogenic CXC chemokine levels in bronchoalveolar lavage fluid after interferon gamma-1b therapy in idiopathic pulmonary fibrosis patients.

BACKGROUND AND AIM: Pulmonary fibrosis is a devastating disease with few treatment options. Angiogenesis that leads to aberrant vascular remodeling is regulated by an opposing balance of angiogenic and angiostatic factors. The present study aims to evaluate the role of three angiogenic (IL-8, ENA-78 and GRO-a) and three angiostatic (MIG, IP-10, ITAC) chemokines in bronchoalveolar lavage fluid (BALF), before and after treatment with Interferon gamma-1b (IFN gamma-1b). PATIENTS AND METHODS: We studied prospectively 20 patients (16 males, 4 females) of median age 68 years (range, 40-75) with histologically confirmed IPF/UIP. Patients were assigned to receive IFN gamma-1b 200 microg sc thrice a week. Angiogenic and angiostatic mediators' levels were measured by ELISA kits. RESULTS: The levels of the angiogenic chemokines significantly decreased after 12 months (mo) of IFN-gamma-1b treatment (median values in pg/ml, IL-8/CXCL8: 640 vs. 81, p<0.05, ENA-78/CXCL5: 191 vs. 51, p<0.005 and GRO-alpha: 1827 vs. 710, p<0.005). No significant differences were detected in the levels of the angiostatic chemokines after therapy (median values in pg/ml, IP-10/CXCL10: 56 vs. 56.5, p=0.6, ITAC/CXCL11: 43 vs. 47, p=0.11). However, a significant decrease in the MIG/CXCL9: 66 vs. 31, p=0.006, has been detected. CONCLUSION: These findings support the notion that IFN gamma may be one of the important mediators regulating angiogenetic balance in IPF. However, IFN gamma-1b decreases MIG levels, finding that in association with no alteration in IP-10 and I-TAC levels, could explain in part the nonbeneficial effect of this drug in IPF.

Biomarkers in COPD.

Chronic Obstructive Pulmonary Disease is characterized by an abnormal inflammatory response of the lungs to noxious particles and gases, caused primarily by cigarette smoking. Although COPD affects the lung, it also produces significant systemic consequences. Inflammation, proteases-antiproteases imbalance, oxidative stress, tissue damage and tissue repair, apoptosis and several genes seem to be involved in the pathogenesis of the disease. The cellular and molecular events underlying COPD pathogenesis are driven by multifunctional molecules including enzymes, cytokines, chemokines, growth factors, lipid mediators and their respective receptors. A large number of biomarkers evaluated in COPD, showed a high degree of redundancy. Nevertheless, current understanding of the pathobiology of COPD suggests a number of biomarkers as potential candidates. The development of relevant markers of lung damage, pulmonary inflammation, and systemic disease will be essential to our further understanding of the natural history of COPD and the discovery of new, effective treatments for its progression. This review summarizes recent findings, on potential pulmonary biomarkers in the induced sputum, the exhaled air condensate, the peripheral blood, the urine, the bronchoalveolar lavage fluid, and in selective cases, in bronchial biopsies.

Simultaneous expression of c-erbB-1, c-erbB-2, c-erbB-3 and c-erbB-4 receptors in non-small-cell lung carcinomas: correlation with clinical outcome.

The expression of c-erbB receptors was immunohistochemically examined in paraffin embedded specimens from non-small-cell lung carcinomas. A total of 209 patients were enrolled [squamous-cell carcinomas (n=59), adenocarcinomas (n=130), large-cell carcinomas (n=15) and giant-cell carcinomas (n=5)]. The HercepTest kit scoring guidelines were used for the interpretation of positivity. C-erbB-1 was overexpressed in older patients, in squamous-cell carcinomas and in poorly-differentiated tumours, whereas c-erbB-2 overexpression with adenocarcinomas and poorly-differentiated tumours. C-erbB-4 overexpression correlated with advanced disease stage. The c-erbB-1/4 pair was the most commonly overexpressed and significantly correlated with female gender, while the c-erbB-1/2 pair with older age. Response to chemotherapy was significantly reduced in patients with tumours overexpressing c-erbB-1 receptor as well as the c-erbB-1/2 and c-erbB-3/4 receptor pairs. Patients' overall survival was significantly correlated with the co-expression of c-erbB-1 and c-erbB-4 receptors. These findings clearly suggest that specific receptors overexpression or co-overexpression is correlated with patients' disease control rate and outcome. A better understanding of the overexpression of the heterodimerized partners of c-erbB family receptors may provide a useful predictive indicator of response to molecular targeted therapies with c-erbB inhibitors.

Effects of antifibrotic agents on TGF-beta1, CTGF and IFN-gamma expression in patients with idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a deadly disease, largely unresponsive to treatment with corticosteroids and immunosuppressives. The aim of this randomized, prospective, open-label study was to characterize the molecular effects of IFN-gamma-1b and colchicine, on biomarkers expression associated with fibrosis (TGF-beta, CTGF) and immunomodulatory/antimicrobial activity (IFN-gamma), in the lungs of patients with IPF. Fourteen (14) patients with an established diagnosis of IPF received either 200 microg of IFN-gamma-1b subcutaneously three times per week, or 1mg of oral colchicine per day, for 24 months. Using RT-PCR assay, we evaluated the transcription levels of transforming growth factor beta1 (TGF-beta1), connective-tissue growth factor (CTGF), and interferon-gamma (IFN-gamma) genes in lung tissue before and after treatment with IFN-gamma-1b or colchicine. Marked mRNA expression of TGF-beta1 and CTGF, but complete lack of interferon-gamma was detected in fibrotic lung tissue at entry. After treatment, both groups exhibited increased expression of IFN-gamma gene at 6 months that was sustained at 24 months. The expression of CTGF and TGF-beta1 remained almost stable before and after treatment, in the IFN-gamma-1b group, while TGF-beta1 was statistically decreased after therapy, in the colchicine group (p=0.0002). Significant difference in DLCO (% pred), was found between the two treatment groups in favor of IFN-gamma-1b group (p=0.04). In addition, the IFN-gamma-1b group showed stability in arterial PO2 while the colchicine group significantly deteriorated (p=0.02). In conclusion, we report the effect of antifibrotic agents (IFN-gamma-1b and colchicine) in TGF-beta, CTGF, and endogenous IFN-gamma gene expression, in human fibrosis. However, extended studies are needed to verify the pathophysiological consequences of these findings.

Role of angiogenesis and vascular remodeling in chronic obstructive pulmonary disease.

Recently, angiogenesis and pulmonary vascular remodeling in COPD has been investigated. It has been hypothesized that endothelial dysfunction might be an initiating event that promotes vessel remodeling in COPD. Inflammatory tissue--a pivotal pathological feature of COPD--often hypoxic, can induce angiogenesis through upregulation of factors such as VEGF or FGF and regulators of angiogenesis such as chemokines (CXC family), acting either as angiogenic or angiostatic. Angiopoietins are distinct molecules that act in association with VEGF at different stages of angiogenic process. The regulation of angiogenesis is determined by a dual, yet opposing balance of angiogenic and angiostatic factors that promote or inhibit neovascularization, respectively, not yet elucidated in detail in COPD. Recent studies suggested an increased expression of VEGF in pulmonary muscular arteries of patients with moderate COPD and also in smokers with normal lung function. This was also associated with enlargement of the arterial wall. However, in patients with severe emphysema, the expression of VEGF tended to be low, despite intense vascular remodelling. Furthermore, it has been suggested that VEGF might be involved in the pathogenesis of emphysema through apoptotic mechanisms. Experimental studies showed that the lung microvascular endothelial cells (including the alveolar septal capillary cells) are particularly vulnerable and dependent on VEGF for their survival. Apoptosis of endothelial, leading to the loss of capillaries may well be a central mechanism in patients with emphysema and muscle wasting. This review article summarizes the current knowledge regarding the contribution of vascular remodeling, as well as the pathogenetic and therapeutic implications of pivotal angiogenic mediators, in COPD.

Active remodeling in idiopathic interstitial pneumonias: evaluation of collagen types XII and XIV.

Fibril-associated collagens with interrupted triple helices (FACITs) XII and XIV act as fibril organizers and assist in the maintenance of uniform fibril size. We investigated the spatial expression patterns of collagens XII and XIV in cryptogenic organizing pneumonia (COP)/organizing pneumonia (OP) and in idiopathic pulmonary fibrosis (IPF)/usual interstitial pneumonia (UIP) and compared them to normal human lung. Study subjects included 10 patients with COP/OP, 10 patients with IPF/UIP, and 8 control subjects. Immunostaining for collagens XII and XIV was carried out in paraffin-embedded human lung tissue sections. Picrosirius red histochemical staining for collagen I expression and electron microcopy to evaluate fibril diameter were also performed. In normal lung, collagens XII and XIV were expressed in perivascular and subpleural connective tissue. In COP/OP, both collagens showed intense staining in perivascular connective tissue, thickened alveolar septae, and subpleural areas. In IPF/UIP, XII and XIV were expressed in perivascular connective tissue, in areas of established fibrosis, and in areas of subpleural thickening. Only collagen XII was expressed in granulation tissue plugs in COP/OP and in fibroblastic foci in IPF/UIP. Collagen type I was overexpressed in fibrotic areas. Electron micrographs revealed obvious fibril diameter alteration and fusion in the same areas. FACITs XII and XIV are expressed in normal and fibrotic lung. Unlike collagen XIV, collagen XII was expressed in granulation tissue plugs in COP/OP and in fibroblast foci in IPF/UIP. This may suggest a possible distinct role for both collagens in the modulation of the extracellular matrix during the onset of fibrotic process.