Intranasal Administration of Type V Collagen Reduces Lung Carcinogenesis through Increasing Endothelial and Epithelial Apoptosis in a Urethane-Induced Lung Tumor Model.

Type V collagen (Col V) is a "minor" component of normal lung extracellular matrix, which is subjected to decreased and abnormal synthesis in human lung infiltrating adenocarcinoma. We previously reported that a direct link between low amounts of Col V and decreased cell apoptosis may favor cancer cell growth in the mouse lung after chemical carcinogenesis. Moreover, this collagen species was able to trigger DNA fragmentation and impair survival of neoplastic cells. In this study, we have extended our investigation with the aim to obtain further evidence that the death induced by Col V-treatment is of the caspase-9 apoptotic type. We used (1) optical and electron microscopy, (2) quantitation of TUNEL-labeled cells and (3) analysis of the expression levels of Col V and selected genes coding for apoptosis-linked factors, by conventional RT-PCR. BALB/c mice were injected intraperitoneally with 1.5 g/kg body weight of urethane. After urethane injection, the animals received intranasal administration of 20 µg/20 µl of Col V every day during 2 months. We report here that Col V treatment was able to determine significant increase in Col V protein and gene expression and in the percentage of TUNEL-positive cells, to up-regulate caspase-9, resulting in low growth of tumor cells. Our data validate chemical carcinogenesis as a suitable "in vivo" model for further and more detailed studies on the molecular mechanisms of the death response induced by Col V in lung infiltrating adenocarcinoma opening new strategies for treatment.

Usual interstitial pneumonia and smoking-related interstitial fibrosis display epithelial to mesenchymal transition in fibroblastic foci.

BACKGROUND: Fibroblastic foci (FF) are a major histological feature of usual interstitial pneumonia (UIP) in idiopathic pulmonary fibrosis (IPF) and collagen vascular diseases (non-IPF). In addition, FF are occasionally associated with smoking-related interstitial fibrosis (SRIF). Recent studies have suggested a role for epithelial to mesenchymal transition (EMT) in pulmonary fibrogenesis. METHODS: Here, we investigated whether EMT was present in patients with IPF (n = 19), non-IPF (n = 17), and SRIF (n = 16) using morphometric immunohistochemistry, electron microscopy, and confocal microscopy. All patients had received lung biopsies or lobectomies for lung cancer. RESULTS: IPF and non-IPF patients displayed restrictive lung function patterns, whereas those with SRIF presented mixed patterns. Cells within FF presented high number of alpha-smooth muscle actin (αSMA)-staining cells; however, the foci of IPF patients showed comparatively lower number. Moreover, colocalization of thyroid transcription factor-1 (TTF1) and αSMA within FF showed low number of staining cells for IPF and SRIF in comparison to non-IPF (p < 0.01). Nevertheless, all groups displayed colocalization of high rate of TTF1(+)-cells and low rate of αSMA(+)-cells within hyperplastic epithelioid cells in FF. Also, we observed areas with low proportion of TTF1(+)cells and αSMA(+)cells, which were present in SRIF and non-IPF more often than IPF (p < 0.001). Electron microscopy revealed small breaks in the alveolar basal lamina, which allowed epithelioid cells to directly contact the collagenous matrix and fibroblasts. Three-dimensional reconstruction revealed intense αSMA staining within some epithelioid cells, suggesting that they had gained a mesenchymal phenotype. CONCLUSIONS: These findings constitute the first report of EMT in SRIF and suggest that EMT occurs more prominently in SRIF and non-IPF than IPF.

Immunohistochemical and morphometric evaluation of COX 1 and COX-2 in the remodeled lung in idiopathic pulmonary fibrosis and systemic sclerosis / Avaliacao imuno-histoquimica e morfometrica de COX-1 e COX-2 no remodelamento pulmonar na fibrose pulmonar idiopatica e na esclerose sistemica

OBJECTIVE: To study the expression of COX-1 and COX-2 in the remodeled lung in systemic sclerosis (SSc) and idiopathic pulmonary fibrosis (IPF) patients, correlating that expression with patient survival. METHODS: We examined open lung biopsy specimens from 24 SSc patients and 30 IPF patients, using normal lung tissue as a control. The histological patterns included fibrotic nonspecific interstitial pneumonia (NSIP) in SSc patients and usual interstitial pneumonia (UIP) in IPF patients. We used immunohistochemistry and histomorphometry to evaluate the expression of COX-1 and COX-2 in alveolar septa, vessels, and bronchioles. We then correlated that expression with pulmonary function test results and evaluated its impact on patient survival. RESULTS: The expression of COX-1 and COX-2 in alveolar septa was significantly higher in IPF-UIP and SSc-NSIP lung tissue than in the control tissue. No difference was found between IPF-UIP and SSc-NSIP tissue regarding COX-1 and COX-2 expression. Multivariate analysis based on the Cox regression model showed that the factors associated with a low risk of death were younger age, high DLCO/alveolar volume, IPF, and high COX-1 expression in alveolar septa, whereas those associated with a high risk of death were advanced age, low DLCO/alveolar volume, SSc (with NSIP), and low COX-1 expression in alveolar septa. CONCLUSIONS: Our findings suggest that strategies aimed at preventing low COX-1 synthesis will have a greater impact on SSc, whereas those aimed at preventing high COX-2 synthesis will have a greater impact on IPF. However, prospective randomized clinical trials are needed in order to confirm that. .

OBJETIVO: Estudar a expressão de COX-1 e COX-2 em áreas pulmonares remodeladas em pacientes com esclerose sistêmica (ES) ou fibrose pulmonar idiopática (FPI) e correlacioná-la com a sobrevida desses pacientes. MÉTODOS: Examinamos espécimes de biópsia pulmonar a céu aberto de 24 pacientes com ES e de 30 pacientes com FPI, utilizando-se tecido pulmonar normal como controle. Os padrões histológicos incluíram pneumonia intersticial não específica (PINE) fibrótica em pacientes com ES e pneumonia intersticial usual (PIU) nos pacientes com FPI. Imuno-histoquímica e histomorfometria foram usadas para avaliar a expressão celular de COX-1 e COX-2 em septos alveolares, vasos e bronquíolos, sua correlação com provas de função pulmonar e seu impacto na sobrevida. RESULTADOS: A expressão de COX-1 e COX-2 em septos alveolares foi significativamente maior em FPI-PIU e ES-PINE do que no tecido controle. Não houve diferença entre FPI-PIU e ES-PINE quanto à expressão de COX-1 e COX-2. A análise multivariada baseada no modelo de regressão de Cox mostrou que os fatores associados a baixo risco de morte foram ter idade menor, valores elevados de DLCO/volume alveolar, FPI, e alta expressão de COX-1 em septos alveolares, ao passo que os fatores associados a alto risco de morte foram ter idade maior, valores baixos de DLCO/volume alveolar, ES (com PINE) e baixa expressão de COX-1 em septos alveolares. CONCLUSÕES: Nossos resultados sugerem que estratégias de prevenção de baixa síntese de COX-1 terão maior impacto sobre a ES, ao passo que as de prevenção de alta síntese de COX-2 terão maior impacto sobre a FPI. Porém, são necessários ensaios clínicos randomizados prospectivos para confirmar essa hipótese. .

Immunohistochemical and morphometric evaluation of COX 1 and COX-2 in the remodeled lung in idiopathic pulmonary fibrosis and systemic sclerosis.

OBJECTIVE: To study the expression of COX-1 and COX-2 in the remodeled lung in systemic sclerosis (SSc) and idiopathic pulmonary fibrosis (IPF) patients, correlating that expression with patient survival. METHODS: We examined open lung biopsy specimens from 24 SSc patients and 30 IPF patients, using normal lung tissue as a control. The histological patterns included fibrotic nonspecific interstitial pneumonia (NSIP) in SSc patients and usual interstitial pneumonia (UIP) in IPF patients. We used immunohistochemistry and histomorphometry to evaluate the expression of COX-1 and COX-2 in alveolar septa, vessels, and bronchioles. We then correlated that expression with pulmonary function test results and evaluated its impact on patient survival. RESULTS: The expression of COX-1 and COX-2 in alveolar septa was significantly higher in IPF-UIP and SSc-NSIP lung tissue than in the control tissue. No difference was found between IPF-UIP and SSc-NSIP tissue regarding COX-1 and COX-2 expression. Multivariate analysis based on the Cox regression model showed that the factors associated with a low risk of death were younger age, high DLCO/alveolar volume, IPF, and high COX-1 expression in alveolar septa, whereas those associated with a high risk of death were advanced age, low DLCO/alveolar volume, SSc (with NSIP), and low COX-1 expression in alveolar septa. CONCLUSIONS: Our findings suggest that strategies aimed at preventing low COX-1 synthesis will have a greater impact on SSc, whereas those aimed at preventing high COX-2 synthesis will have a greater impact on IPF. However, prospective randomized clinical trials are needed in order to confirm that.

The effects of chronic exposure to traffic derived air pollution on the ocular surface.

OBJECTIVES: The purpose of this study was to explore the clinical relevance of chronic exposure to ambient levels of traffic derived air pollution on the ocular surface. METHODS: A panel study involving 55 volunteers was carried out in São Paulo, Brazil. We measured the mean individual levels of nitrogen dioxide (NO(2)) exposure for 7 days. All subjects answered the Ocular Symptom Disease Index (OSDI) and a symptoms inventory. Subsequently, subjects underwent Schirmer I test, biomicroscopy, vital staining and tear breakup time (TBUT) assessment. Subject's mean daily exposure to NO(2) was categorized in quartiles. Statistical analysis was performed using one-way ANOVA, Tukey HSD and Chi-Square tests. RESULTS: A dose-response pattern was detected between OSDI scores and NO(2) quartiles (p<0.05). There was a significant association between NO(2) quartiles and reported ocular irritation (Chi(2)=9.2, p<0.05) and a significant negative association between TBUT and NO(2) exposure (p<0.05, R=-0.316, Spearman's correlation). There was a significant increase in the frequency of meibomitis in subjects exposed to higher levels of NO(2) (p<0.05). CONCLUSIONS: Subjects exposed to higher levels of traffic derived air pollution reported more ocular discomfort symptoms and presented greater tear film instability, suggesting that the ocular discomfort symptoms and tear breakup time could be used as convenient bioindicators of the adverse health effects of traffic derived air pollution exposure.