Overexpression of matrix metalloproteinase-9 in adolescents with primary spontaneous pneumothorax for surgical intervention.

OBJECTIVE: To determine gene expression profiles associated with bullae formation in patients with primary spontaneous pneumothorax and to identify candidate genes associated with surgical intervention. METHODS: Twenty-four adolescents with primary spontaneous pneumothorax were enrolled prospectively. A global gene expression analysis of 9 paired lung biopsies (lesion and normal adjacent sites) was performed to identify differentially expressed genes associated with spontaneous pneumothorax. Pathway and network analysis was performed using the Database for Annotation, Visualization and Integrated Discovery web tool. Candidate genes and encoding proteins were assessed in blood samples and compared between patients with pneumothorax and healthy control patients. RESULTS: A total of 1519 differentially expressed transcripts corresponding to known genes were identified comparing the lesion lung with paired adjacent normal lung. The altered genes were mainly associated with focal adhesion and extracellular matrix-receptor interaction pathways. Genes involved in proteolysis and peptidase activity were up-regulated predominantly, especially matrix metalloproteinase-1 and -9 genes. Compared with the recovery stage, blood levels of matrix metalloproteinase-9/tissue inhibitor of metalloproteinase-1 were increased at the acute stage in patients with pneumothorax and, when compared between patients treated operatively with those treated nonoperatively, were also significantly greater. In addition, ratios of their serum levels were significantly greater in patients with pneumothorax compared with healthy control patients. Furthermore, matrix metalloproteinase-9 was predominantly overexpressed in neutrophils, alveolar macrophages, and mesothelial cells of lung biopsies. CONCLUSIONS: An imbalance of cell-extracellular matrix interactions appears to be associated with primary spontaneous pneumothorax. Matrix metalloproteinase-9 overexpression may particularly play a role in contributing to pleural porosity for surgical intervention.

Association of MMP-2 and MMP-9 expression with recurrences in primary spontaneous pneumothorax.

Primary spontaneous pneumothorax (PSP) is a common benign problem. However, PSP recurrence is still a troublesome complication for most patients. This study intended to determine the role of matrix metalloproteinase-2 (MMP-2) and MMP-9 in type II pneumocytes of patients with PSP and its relation with recurrence. Ninety-one patients who had undergone needlescopic video-assisted thoracoscopic surgery wedge resection of lung with identifiable blebs for PSP were included in this study. Immunohistochemical (IHC) staining was used to measure the expression of MMP-2 and MMP-9 in lung tissues of PSP patients. The results were further correlated with clinicopathological parameters and recurrence rates using chi-square or Fisher's exact test. The value of MMP-2 and MMP-9 for overall recurrence was analyzed by univariate and multivariable Cox regression model. IHC data revealed that MMP-2 and MMP-9 staining was predominantly observed in type II pneumocytes of patients with PSP. We found that MMP-2 and MMP-9 expression in PSP, especially male PSP patients, was significantly correlated with recurrence. In the univariate and multivariate analyses, MMP-2 and MMP-9 were statistically significant risk factors for overall recurrence in PSP patients. Therefore, high expression levels of MMP-2 and MMP-9 in type II pneumocytes show a positive correlation with PSP recurrence risk. Further studies are needed to validate whether reduction of MMP-2 and MMP-9 expression may be a promising way for decreasing the risk of PSP recurrence in the future.

Telomerase mutations in smokers with severe emphysema.

Mutations in the essential telomerase genes TERT and TR cause familial pulmonary fibrosis; however, in telomerase-null mice, short telomeres predispose to emphysema after chronic cigarette smoke exposure. Here, we tested whether telomerase mutations are a risk factor for human emphysema by examining their frequency in smokers with chronic obstructive pulmonary disease (COPD). Across two independent cohorts, we found 3 of 292 severe COPD cases carried deleterious mutations in TERT (1%). This prevalence is comparable to the frequency of alpha-1 antitrypsin deficiency documented in this population. The TERT mutations compromised telomerase catalytic activity, and mutation carriers had short telomeres. Telomerase mutation carriers with emphysema were predominantly female and had an increased incidence of pneumothorax. In families, emphysema showed an autosomal dominant inheritance pattern, along with pulmonary fibrosis and other telomere syndrome features, but manifested only in smokers. Our findings identify germline mutations in telomerase as a Mendelian risk factor for COPD susceptibility that clusters in autosomal dominant families with telomere-mediated disease including pulmonary fibrosis.

Overexpression of matrix metalloproteinases in lung tissue of patients with primary spontaneous pneumothorax.

BACKGROUND: Although blebs and bullae are frequently found in the apexes of lungs of patients with primary spontaneous pneumothorax (PSP), its pathogens remain unclear. OBJECTIVES: To examine the role of proteases [matrix metalloproteinase (MMP)-2, MMP-7 and MMP-9] and antiproteases [tissue inhibitors of metalloproteinase (TIMP)-1, TIMP-2, TIMP-3 and TIMP-4] in the pathogenesis of PSP. METHOD: Fifty consecutive PSP patients who received standard surgical care were enrolled in the study. Lung tissues from 20 patients with stage I non-small cell lung cancer were used as a control. Immunohistochemistry (IHC), reverse transcription-polymerase chain reaction (RT-PCR) and gelatin zymography were used to evaluate the expression of MMP and TIMP in the lung tissue of patients with PSP. RESULTS: Overexpression of MMP-2, MMP-7 and MMP-9 was found in the afflicted lung by IHC, zymography and RT-PCR. By IHC, higher expression of MMP-2 and MMP-9 in PSP patients was identified in alveolar macrophages and type II pneumocytes (88 and 92% of patients in macrophages, and 72 and 70% of patients in type II pneumocytes, respectively). MMP-2, MMP-7 and MMP-9 expression in patients was higher in mesothelial cells (66, 76 and 76%). Overexpression of TIMP-2 was detected in the extracellular matrix around bullae and blebs. Expression levels of TIMP-1, TIMP-3 and TIMP-4 were negligible (<10% of cells) in both PSP patients and controls. CONCLUSIONS: MMP-2, MMP-9, MMP-7 and TIMP-2 were upregulated in PSP lesions. These results suggest that an imbalance between the expression of proteases and antiproteases may be involved in the pathogeneses of PSP.

[Cyclooxigenase-2 levels are increased in the lung tissue and bronchial tumors of patients with chronic obstructive pulmonary disease]. / La ciclooxigenasa-2 está regulada al alza en el pulmón y en los tumores bronquiales de pacientes con enfermedad pulmonar obstructiva crónica.

INTRODUCTION: The expression of cyclooxygenase 2 (COX-2) is usually increased in inflammation and cancer. This study examines the expression of COX-2 in the lung of chronic obstructive pulmonary disease (COPD) patients with lung cancer. METHODS: We studied 44 male patients with bronchial cancer (27 squamous carcinoma and 17 adenocarcinoma). Samples were obtained from the pulmonary parenchyma, from the bronchial mucosa adjacent to the tumor and from the tumor itself. Lung tissue specimens from 14 patients with pneumothorax were used as control. The mRNA and the COX-1 and COX-2 proteins were assessed by RT-PCR and Western blot, respectively. RESULTS: COX-1 and COX-2 mRNA levels were significantly higher in the lung parenchyma of COPD patients than in the control subjects. COX-2 mRNA levels were also higher in the lung parenchyma than in both tumor and airway tissue samples procured from COPD patients. There were no differences in the COX-2 mRNA levels between squamous carcinoma and adenocarcinoma. In contrast, COX-2 protein levels were significantly higher in tumors than in lung parenchyma and airways. COX-2 protein levels were higher in adenocarcinoma compared with squamous carcinoma. CONCLUSION: This study shows that in COPD, the pathway of cyclooxygenase is activated and associated with an increase in the expression of COX-2 in lung tumors. These observations suggest that COX-2 is possibly involved in the association between COPD and cancer.

Induction of heme oxygenase-1, biliverdin reductase and H-ferritin in lung macrophage in smokers with primary spontaneous pneumothorax: role of HIF-1alpha.

BACKGROUND: Few data concern the pathophysiology of primary spontaneous pneumothorax (PSP), which is associated with alveolar hypoxia/reoxygenation. This study tested the hypothesis that PSP is associated with oxidative stress in lung macrophages. We analysed expression of the oxidative stress marker 4-HNE; the antioxidant and anti-inflammatory proteins heme oxygenase-1 (HO-1), biliverdin reductase (BVR) and heavy chain of ferritin (H-ferritin); and the transcription factors controlling their expression Nrf2 and HIF-1alpha, in lung samples from smoker and nonsmoker patients with PSP (PSP-S and PSP-NS), cigarette smoke being a risk factor of recurrence of the disease. METHODOLOGY/PRINCIPAL FINDINGS: mRNA was assessed by RT-PCR and proteins by western blot, immunohistochemistry and confocal laser analysis. 4-HNE, HO-1, BVR and H-ferritin were increased in macrophages from PSP-S as compared to PSP-NS and controls (C). HO-1 increase was associated with increased expression of HIF-1alpha mRNA and protein in alveolar macrophages in PSP-S patients, whereas Nrf2 was not modified. To understand the regulation of HO-1, BVR and H-ferritin, THP-1 macrophages were exposed to conditions mimicking conditions in C, PSP-S and PSP-NS patients: cigarette smoke condensate (CS) or air exposure followed or not by hypoxia/reoxygenation. Silencing RNA experiments confirmed that HIF-1alpha nuclear translocation was responsible for HO-1, BVR and H-ferritin induction mediated by CS and hypoxia/reoxygenation. CONCLUSIONS/SIGNIFICANCE: PSP in smokers is associated with lung macrophage oxidative stress. The response to this condition involves HIF-1alpha-mediated induction of HO-1, BVR and H-ferritin.

Levels of superoxide dismutase and malondialdehyde in primary spontaneous pneumothorax.

The aim of the present study is to determine whether patients with primary spontaneous pneumothorax (PSP) are subject to oxidative stress. For this purpose, we measured the activities of red blood cell superoxide dismutase, which is an antioxidant enzyme, and the level of plasma malondialdehyde, which is one of the lipid peroxidation markers, in a group of patients with PSP. The study was carried out with 16 patients with PSP and 24 healthy individuals. The two groups were similar to each other in terms of sex, age and smoking attitudes. Erythrocyte superoxide dismutase activity was found to be significantly lower in patients with PSP than in the control group (p < 0.01). The plasma malondialdehyde levels were significantly high in patients with PSP (p < 0.01). Our results suggest that oxidative stress may contribute to the pathogenesis of PSP.

Effect of pneumothorax on pleurodesis induced with talc in rabbits.

OBJECTIVE: The purpose of this study was to determine if a small pneumothorax would influence the pleurodesis resulting from talc instillation. METHODS: Sixty rabbits received an intrapleural injection of 400 mg/kg talc slurry. One half also received 10 mL of air intrapleurally after the talc. Ten rabbits in each group were killed 2, 14, and 28 days after instillation. RESULTS: Two days after the injection, the mean volume of air in the animals that had received the air was 7.5+/-0.4 mL. There was no air present in any other rabbits. The volume of pleural fluid and the pleural fluid glucose, protein, cell count, and differential were similar in both groups on day 2, while the LDH level was significantly higher in the air group (p<0.05). The degree of gross adhesions and microscopic fibrosis was similar in both groups and increased with time. CONCLUSIONS: A small pneumothorax does not decrease the efficacy of talc pleurodesis in our experimental model. These results suggest that the presence of a small amount of intrapleural air is not a contraindication to talc pleurodesis in humans.

[Alternation of protease inhibitors and hemostasis system in treatment of spontaneous pneumothorax]. / Izmenenie ingibitorov proteaz i sistemy gemostaza pri lechenii spontannogo pnevmotoraksa.

3 groups of 37 patients were examined, in which for treatment of spontaneous pneumothorax drainage of pleural cavity and medicamentous pleurodesis with tetracycline hydrochloride and 4% solution of sodium bicarbonate were used. Interdependence of clinical criteria and level of protease inhibitors were evaluated, as well as the basic components of hemostasis. The best effectiveness of treatment in carrying out chemical pleurodesis was demonstrated, especially when 4% sodium bicarbonate solution was used. At the same time the application of this agent has evoked the most evident changes in values of hemostasis and protease inhibitors. The possibility of use of the above mentioned biochemical in dices together with clinical criteria for the evaluation of effectiveness of treatment of the unspecific spontaneous pneumothorax is stressed.

[The use of streptokinase preparations in pleural empyema and pyopneumothorax]. / Primenenie preparatov streptokinazy pri émpieme plevry i piopnevmotorakse.

Prevailing fibrin-formation in the pleural cavity entails hypoactivity of trypsin-like proteinases and a high inhibitory potential in the serum and pleural exudate. Streptokinase preparations appeared an effective means of pharmacological pulmonary decortication in patients with high pleural levels of plasminogen. The authors obtained higher efficacy of conservative therapy for pyothorax when they used a specially designed technique of intrapleural administration of streptokinase-activated fresh frozen plasma of the same group. The outcomes of the disease were also improved noticeably.

The antielastase screen of the lower respiratory tract of alpha 1-proteinase inhibitor-sufficient patients with emphysema or pneumothorax.

The present study was aimed at testing whether alpha 1-proteinase inhibitor-sufficient patients with lung emphysema or idiopathic spontaneous pneumothorax have an impaired antielastase protection at the lung alveolar level. We have collected bronchoalveolar lavage fluids (BALF) from 20 PIMM emphysematous patients (44 +/- 12 yr), 24 patients with pneumothorax but no radiologic evidence of emphysema (30 +/- 11 yr), 32 healthy subjects (27 +/- 6 yr), and 56 patients with sarcoidosis (30 +/- 11 yr). The BALF were assayed for immunoreactive albumin, alpha 1-proteinase inhibitor (alpha 1PI), leukocyte elastase-alpha 1PI complex (LE-alpha 1PI), and mucus proteinase inhibitor (MPI) as well as for porcine pancreatic elastase inhibitory capacity, a measure of active alpha 1PI. The healthy subjects and the patients with emphysema or pneumothorax had comparable levels of total and active alpha 1PI and total MPI. In contrast, the levels of LE-alpha 1PI complex were elevenfold higher in patients with emphysema than in normal subjects (p = 0.021) and tended to increase with the severity of the disease because they were negatively correlated with FEV1/FVC% (r = -0.55; 0.05 less than p less than 0.1). They did not vary with age in a population of patients with sarcoidosis (r = 0.03), suggesting that their eleven-fold increase in emphysematous patients is not related to the age of these subjects. Patients with pneumothorax had levels of LE-alpha 1PI complex that did not significantly differ from those of normal subjects (p = 0.24).(ABSTRACT TRUNCATED AT 250 WORDS)

Interferon enhances tryptophan metabolism by inducing pulmonary indoleamine 2,3-dioxygenase: its possible occurrence in cancer patients.

Human lungs bearing cancer (n = 27) exhibited up to an approximately 20-fold [on average approximately 5-fold (P less than 0.005)] increase in the enzyme activity that degrades tryptophan to form formylkynurenine, in comparison with lungs with benign lesions (blebs) (n = 7) taken as controls. On the basis of molecular and kinetic properties, this activity was ascribed to indoleamine 2,3-dioxygenase (IDO) [indoleamine:oxygen 2,3-oxidoreductase (decyclizing)]. In vitro studies with human lung slices revealed that human interferon gamma (IFN-gamma) induced the de novo synthesis of IDO dose dependently (10-10(4) units/ml), and at maximum the activity reached nearly 100 times that in the control lungs described above. Human IFN-alpha also served as an inducer, but it was two to three orders of magnitude less potent than IFN-gamma relative to the antiviral titers, suggesting that IFN-gamma is the main mediator of the IDO induction. IDO thus induced in slices avidly metabolized tryptophan in situ: Upon a 24-hr incubation of lung slices pretreated with varied doses of IFN-gamma (10-10(3) units/ml), up to 96% of the tryptophan in the slices was depleted and up to 70% of the tryptophan in the medium was converted, mainly to formylkynurenine, kynurenine, or both. The foregoing results suggest that an IFN-mediated induction of IDO also takes place in vivo in human lungs as a response to cancer, leading to metabolic consequences such as depletion of tryptophan and accumulation of (formyl)kynurenine, which may provide a unique host defense mechanism.