0
Original Research: COPD |

Simultaneous Assessment of Hepatocyte Growth Factor and Vascular Endothelial Growth Factor in Epithelial Lining Fluid From Patients With COPDRole of Growth Factors in COPD FREE TO VIEW

Hiroshi Kanazawa, MD, PhD; Yoshihiro Tochino, MD, PhD; Kazuhisa Asai, MD, PhD; Kazuto Hirata, MD, PhD
Author and Funding Information

From the Department of Respiratory Medicine, Graduate School of Medicine, Osaka City University, Osaka, Japan.

CORRESPONDENCE TO: Hiroshi Kanazawa, MD, PhD, Department of Respiratory Medicine, Graduate School of Medicine, Osaka City University, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan; e-mail: kanazawa-h@med.osaka-cu.ac.jp


FOR EDITORIAL COMMENT SEE PAGE 1135

FUNDING/SUPPORT: This work was supported by JSPS KAKENHI [Grant 20590901].

Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details.


Chest. 2014;146(5):1159-1165. doi:10.1378/chest.14-0373
Text Size: A A A
Published online

BACKGROUND:  Hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF) are involved in the pathogenesis of various lung diseases. This study was designed to determine the possible interactions of these growth factors in the development of COPD.

METHODS:  We measured the levels of HGF and VEGF in epithelial lining fluid obtained from central or peripheral airways using a bronchoscopic microsampling technique in 10 never smokers, 14 smokers without COPD, and 24 smokers with COPD. We also evaluated whether their levels were correlated with pulmonary function parameters and the grade of low attenuation area (LAA) observed in high-resolution CT scans.

RESULTS:  HGF and VEGF levels in the peripheral airways of smokers with COPD were significantly lower than those in never smokers and smokers without COPD. In smokers with COPD, HGF and VEGF levels of the peripheral airways inversely correlated with the degree of airway obstruction and diffusing capacity of the lung. The HGF and VEGF levels also correlated with the grade of LAA. Although the VEGF levels of smokers with and without COPD overlapped considerably, HGF levels were markedly higher in smokers without COPD.

CONCLUSIONS:  Upregulated HGF probably compensated for the reduced levels of VEGF and preserved the pulmonary function in smokers without COPD. By contrast, both HGF and VEGF levels were decreased in smokers with COPD, which likely led to the development of COPD. Thus, the level of HGF relative to that of VEGF may be a reliable indicator of the risk for COPD.

Figures in this Article

COPD is associated with an abnormal inflammatory response of the lung, which results in airway obstruction, destruction of parenchyma, and development of emphysema.1 There are significant correlations between the lung function, airway wall area, degree of luminal occlusion, and inflammatory infiltrate in the small airways.2 Thus, chronic inflammation and tissue remodeling in small airways contributes to the airway obstruction in COPD. Cigarette smoking is a major cause of COPD and damages the lungs through a variety of mechanisms. Cigarette smoke exposure alters the lung microenvironment with an excessive degradation of extracellular matrix proteins and apoptosis of alveolar epithelial and endothelial cells.3

Hepatocyte growth factor (HGF) is a multifunctional peptide originally recognized for its effect on the proliferation of various epithelial cells.4,5 In animal models, overexpression of HGF promotes alveolar epithelial repair following elastase- and bleomycin-induced lung injury.6,7 Thus, HGF appears to play an important role in the maintenance of the lung structure following lung injury. In addition, HGF acts on endothelial cells.810 Vascular endothelial growth factor (VEGF) is also a potent mitogen for endothelial cells and promotes angiogenesis.11 Consequently, both HGF and VEGF promote endothelial cell survival and favor angiogenesis. The decreased VEGF has been shown to be involved in the pathophysiology of COPD via endothelial cell apoptosis.12,13 We have previously established the method for the measurement of biochemical constituents of epithelial lining fluid (ELF) samples obtained from the central or peripheral airways using a bronchoscopic microsampling technique.14 Using this method, we simultaneously measured HGF and VEGF in ELF from central or peripheral airways of patients with COPD, smokers with no airflow obstruction, and nonsmoking control subjects and examined the possible interactions of HGF and VEGF in the development of COPD.

Subjects

This study enrolled 10 never smokers, 14 smokers without COPD, and 24 smokers with COPD from the outpatient clinic of Osaka City University Hospital. All smokers were former smokers and had stopped smoking for > 1 year. Study subjects who agreed to undergo ELF samplings were consecutively selected and were subjected to bronchoscopic examination to identify the cause of persistent cough or small peripheral nodules. All study subjects underwent pulmonary function tests by using a CHESTAC-8800 unit (CHEST MI Inc). FEV1 and FVC were examined, and the best of three consecutive attempts of spirometric measurements were recorded. In addition, the diffusing capacity of the lung for carbon monoxide (Dlco) was measured in all subjects. In all subjects, chest CT scans showed absence of abnormal diffuse interstitial infiltrates, and results of arterial blood gas analysis results were normal. All patients with COPD satisfied the GOLD (Global Initiative for Chronic Obstructive Lung Disease) criteria for the diagnosis.15 All data in patients with COPD were collected at the time of diagnosis before administration of any medications. All subjects gave their written informed consent for participation in the study, which was approved by the ethics committee of Osaka City University (#685).

Bronchoscopic Microsampling Technique

ELF was obtained as we previously described.16,17 In all subjects, bronchial microsampling from the second bronchus was performed using the microsampling probe (BC-402C; Olympus Corporation) (central airway sample). Following this, a thin, flexible fiber-optic bronchoscope was inserted into the lung, and ELF from the seventh or eighth lower lobe bronchioles was collected under direct observation using an ultrafine probe (BC-401C; Olympus Corporation) (peripheral airway sample). Previous studies examined several biochemical constituents of ELF using a microsampling technique.1820 They ensured the repeatability and reproducibility of this method by performing multiple times at different airway sites or same airway sites in the same subject. However, we did not perform HGF and VEGF measurements more than once in the same subject for ethical reasons. Therefore, we could not determine the repeatability of HGF and VEGF concentrations in this study. To date, the bronchoscopic microsampling technique has not been standardized. If we used the same probes for central and peripheral airways, we may injure peripheral airways wall and induce the contamination of blood. Therefore, the microsampling probe used for peripheral airways has a smaller inner diameter than that used for the central airways (1.1 mm vs 1.9 mm). Moreover, we already determined that the differences in concentrations of mediators could not be explained by the different probes.14,17

Measurement of HGF and VEGF Levels in ELF

The concentrations of HGF and VEGF in ELF samples were measured using enzyme-linked immunosorbent assay (HGF ELISA kit: Otsuka Pharmaceutical Co, Ltd; VEGF ELISA kit: R&D Systems, Inc). The limits of HGF and VEGF detection were 0.08 ng/mL and 15.6 pg/mL, respectively.

Grade of Low Attenuation Area on High-Resolution CT Scans

Before entering the study, all patients with COPD underwent a high-resolution CT (HRCT) scan, which was used to evaluate the degree of lung emphysematous changes. Four 1-mm-thick slices were obtained at three anatomic levels and at full inspiration near the superior margin of the aortic arch (level of the upper lung field), at the level of the carina (level of the middle lung field), and at the level of the orifice of the inferior pulmonary veins (level of the lower lung field). Low attenuation area (LAA) was scored visually in each bilateral lung field according to the method of Goddard et al.21 Total scores were calculated, and the severity of emphysema was graded as follows: score 0, LAA < 5%; score 1, 5% < LAA < 25%; score 2, 25% < LAA < 50%; score 3, 50% < LAA < 75%; score 4, LAA > 75%; grade 0, total score = 0; grade 1, total score = 1 to 6; grade 2, total score = 7 to 12; grade 3, total score = 13 to 18; grade 4, total score = 19 to 24. HRCT images were analyzed independently by two chest physicians who had not received clinical information about the subjects.

Statistical Analysis

All values are presented as the median (interquartile range). When multiple comparisons of nonparametric data between groups were performed, significant intergroup variability was first established with use of the Kruskal-Wallis test. The Mann-Whitney U test was then used for intergroup comparisons. The Wilcoxon signed-rank test was also used for comparisons of variables between central and peripheral airways. The significance of correlations was evaluated by determining Spearman rank correlation coefficients. In all statistical analyses, P value < .05 was considered significant.

The clinical characteristics of the 10 never smokers, 14 smokers without COPD, and 24 smokers with COPD are shown in Table 1. The three groups were well matched for sex and age. Although smoking indexes of smokers with and without COPD were similar, FEV1, FEV1/FVC, and Dlco were significantly lower in smokers with COPD.

Table Graphic Jump Location
TABLE 1 ]  Clinical Characteristics of Study Subjects

All values are presented as median (interquartile range) unless otherwise noted. Dlco = diffusing capacity of the lung for carbon monoxide.

a 

P < .01 compared with never smokers.

b 

P < .01 compared with smokers without COPD.

c 

P < .05 compared with never smokers.

We successfully measured HGF and VEGF levels in ELF separately obtained from central or peripheral airways. The sampling method had no detrimental effects on baseline lung function and oxygenation during the procedure. HGF levels were relatively low in ELF obtained from central airways (HGF in the central airways; never smokers: 11.5 [10.1-13.6] ng/mL; smokers without COPD: 17.2 [13.8-24.4] ng/mL; smokers with COPD: 7.3 [1.8-10.6] ng/mL) (Fig 1). However, their levels were markedly higher in the peripheral airways than in the central airways (HGF in the peripheral airways; never smokers: 84.0 [78.0-108.0] ng/mL; smokers without COPD: 121.5 [96.0-145.0] ng/mL; smokers with COPD: 25.0 [2.4-55.0] ng/mL). Furthermore, the HGF level in the peripheral airways was significantly higher in smokers without COPD than in never smokers. By contrast, the HGF level was significantly lower in smokers with COPD than in smokers without COPD. Compared with that in never smokers, the VEGF level in the central airways was lower in smokers without COPD, and its level in smokers with COPD was even lower (never smokers: 11.3 [8.2-15.5] ng/mL; smokers without COPD: 5.5 [4.0-8.4] ng/mL; smokers with COPD: 4.9 [3.1-8.3] ng/mL) (Fig 2). Moreover, the VEGF level in the peripheral airways was significantly lower in smokers with COPD than in never smokers and smokers without COPD (never smokers: 27.0 [20.5-38.5] ng/mL; smokers without COPD: 12.0 [8.5-16.6] ng/mL; smokers with COPD: 3.8 [1.8-7.5] ng/mL).

Figure Jump LinkFigure 1 –  Comparisons of HGF levels in epithelial lining fluid from central or peripheral airways in never smokers, smokers without COPD, and smokers with COPD. Each bar represents the median value. *P < .01 compared with central airways from never smokers. ‡P < .01 compared with central airways from smokers without COPD. #P < .01 compared with central airways from smokers with COPD. HGF = hepatocyte growth factor.Grahic Jump Location
Figure Jump LinkFigure 2 –  Comparisons of VEGF levels in epithelial lining fluid from central or peripheral airways in never smokers, smokers without COPD, and smokers with COPD. Each bar represents the median value. *P < .01 compared with central airways from never smokers. ‡P < .01 compared with central airways from smokers without COPD. VEGF = vascular endothelial growth factor.Grahic Jump Location

In smokers with COPD, we evaluated the correlations between HGF and VEGF levels in ELF of the peripheral airways and the pulmonary function parameters (Table 2). The HGF level showed significant correlation with FEV1 and Dlco. The VEGF level also showed good correlation with FEV1, FEV1/FVC, and Dlco. We also analyzed the grade of LAA based on HRCT imaging in smokers with COPD (grade 1: n = 4; grade 2: n = 9; grade 3: n = 7; grade 4: n = 4). Although the grade of LAA did not show significant correlations with HGF and VEGF levels of central airways (Fig 3), this parameter correlated well with the levels of HGF and VEGF found in the peripheral airways (HGF: r = −0.83, P < .001; VEGF: r = −0.71, P < .001) (Fig 4).

Table Graphic Jump Location
TABLE 2 ]  Association Between HGF and VEGF Levels in ELF of Peripheral Airways and Pulmonary Function Parameters in Smokers With COPD

ELF = epithelial lining fluid; HGF = hepatocyte growth factor; VEGF = vascular endothelial growth factor. See Table 1 legend for expansion of other abbreviation.

Figure Jump LinkFigure 3 –  Correlations between HGF and VEGF levels in epithelial lining fluid from central airways and the grade of LAA in smokers with COPD. A, HGF. B, VEGF. LAA = low attenuation area; N.S. = not significant. See Figure 1 and 2 legends for expansion of other abbreviations.Grahic Jump Location
Figure Jump LinkFigure 4 –  Correlations between HGF and VEGF levels in epithelial lining fluid from peripheral airways and the grade of LAA in smokers with COPD. See Figure 1, 2, and 3 legends for expansion of abbreviations.Grahic Jump Location

Figure 5 shows the distribution of the HGF and VEGF levels observed in smokers with and without COPD. There was considerable overlap in the VEGF levels of the two groups. However, HGF levels were markedly higher in smokers without COPD than in smokers with COPD.

Figure Jump LinkFigure 5 –  Distribution of HGF and VEGF levels in smokers with and without COPD. ○ = smokers without COPD; ● = smokers with COPD. See Figure 1 and 2 legends for expansion of abbreviations.Grahic Jump Location

In this study, we found that the HGF level in ELF obtained from the central airways was relatively low in all the three groups. Compared with those of never smokers, elevated levels of HGF from the peripheral airways of smokers without COPD were observed. By contrast, HGF levels were significantly lower in smokers with COPD than in both never smokers and smokers without COPD. The effects of cigarette smoking on the lung HGF levels are not fully consistent. It has been reported that there is an increased expression of HGF in the lungs of smokers22 and that the HGF levels decreased in patients with pulmonary emphysema.23 Thus, our results were consistent with these earlier reports.

The cellular origins of HGF in ELF remain to be identified. One of the essential sources of this molecule is lung fibroblasts. A previous study showed that oxidative stress and proinflammatory cytokines induced sustained transcription of HGF mRNA in lung fibroblasts.24 Cigarette smoking may cause excessive oxidative stress and induce proinflammatory cytokines, thereby leading to upregulation of HGF. Our data suggest that conflicting changes in HGF levels of smokers with and without COPD are not related to cigarette smoking per se. Cultured lung fibroblasts obtained from patients with pulmonary emphysema were reported to produce and secrete less HGF than those from control subjects.23 This attenuated HGF production and secretion was associated with a lower proHGF mRNA content of the fibroblasts from patients with emphysema. It appears that COPD itself further contributes to the increased susceptibility of lung fibroblasts to cigarette smoke. Alternatively, lung fibroblasts from these individuals were intrinsically more vulnerable to cigarette smoke. Regardless of which explanation holds true, altered properties of lung fibroblasts may contribute to the downregulated HGF in COPD.

We found that the VEGF level in ELF obtained from smokers without COPD was significantly lower than that from never smokers and that its levels were even lower in smokers with COPD. Previous studies have shown similar trends in VEGF levels in the induced sputum and BAL samples obtained from smokers with and without COPD.25,26 The lower VEGF levels are attributable to endothelial cell apoptosis of the lung in COPD. Although our data indicate that cigarette smoke downregulates VEGF, it is unlikely that this is solely responsible for the development of COPD. It is conceivable that cigarette smoke also affects the levels of other growth factors, including HGF. However, a reduction in the absolute quantity of VEGF, when accompanied by significantly lower levels of HGF seen in smokers with COPD, could potentially contribute to the development of COPD. To test this hypothesis, we evaluated the correlations between HGF and VEGF levels of the peripheral airways and the results of pulmonary function tests in smokers with COPD. As a result, significant correlations between HGF level of the peripheral airways and the pulmonary function parameters were identified. Similarly, VEGF levels of the peripheral airways closely correlated with the degree of airflow obstruction and diffusing capacity of the lung. Together with these findings, our results suggest that the lower levels of HGF and VEGF in the peripheral airways are associated with increased severity of COPD. We also analyzed the grade of LAA based on HRCT imaging in smokers with COPD. Decrease in Dlco in patients with COPD is a reflection of the alveolar destruction and is known to be closely correlated with the grade of LAA. Notably, the grade of LAA in smokers with COPD also significantly correlated with HGF and VEGF levels of the peripheral airways but not those of the central airways.

Downregulation of HGF may result in excessive apoptosis of alveolar epithelial cells and contribute to the incomplete alveolar repair. The integrity of alveolar epithelial cells is important for maintaining pulmonary function and for preventing the development of lung emphysematous changes.27,28 A previous study demonstrated that cigarette smoke exposure resulted in dose-dependent injury of alveolar epithelial cells and that HGF inhibited cigarette smoke-induced damage to alveolar epithelial cells.29 In this respect, the proliferation of type 2 pneumocytes may reflect the need for timely repair of injured alveolar epithelial cells induced by smoking. HGF can induce activated extracellular signal-regulated kinase 1/2,30,31 and HGF-extracellular signal-regulated kinase 1/2 signaling may stimulate the proliferation of type 2 pneumocytes.32 The inhibition of epithelial cell apoptosis by HGF will preserve the functions of lung endothelial cells,33,34 and HGF also directly prevents the apoptosis of endothelial cells. Therefore, HGF might regulate lung tissue homeostasis against the downregulated VEGF. Studies in humans and animal models have shown that deficiencies in VEGF signaling are associated with the development of COPD.35,36 The abilities of HGF and VEGF to modulate apoptosis in both epithelial and, indirectly, endothelial cells suggests a coordinated effect on the lung structure. Our results suggest that HGF and VEGF may coordinate to orchestrate the regulation of pathologic and physiologic homeostasis in the lung.

There are several limitations in this study. Since the number of subjects enrolled in our study was relatively small, further studies are warranted to examine whether HGF and VEGF levels in ELF of the peripheral airways are reliable markers of alveolar destruction. Second, we revealed an association between HGF and VEGF levels and the degree of alveolar destruction but did not investigate the direct causality of this association. Third, there are various methods for establishing the pathophysiological characteristics of COPD, each with their own merits and limitations. There is also considerable diversity in the microsampling techniques adopted to perform and no agreed gold standard. However, the weight of evidence supports the wide use of our microsampling method for the investigating the pathogenesis of COPD.

Upregulated HGF probably compensated for the reduced levels of VEGF and preserved the pulmonary function in smokers without COPD. By contrast, both HGF and VEGF levels were decreased in smokers with COPD, which likely led to the development of COPD. Thus, the level of HGF relative to that of VEGF may be an indicator of the risk for COPD.

Author contributions: H. K. had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. H. K. and K. H. contributed to study design, data analysis, and manuscript writing and preparation; H. K., Y. T., and K. A. contributed to data collection; H. K., Y. T., K. A., and K. H. contributed to reviewing, editing, and approving the manuscript; and K. H. contributed to participant recruitment.

Financial/nonfinancial disclosures: The authors have reported to CHEST that no potential conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.

Role of sponsors: The sponsor had no role in the design of the study, the collection and analysis of the data, or in the preparation of the manuscript.

Dlco

diffusing capacity of the lung for carbon monoxide

ELF

epithelial lining fluid

HGF

hepatocyte growth factor

HRCT

high-resolution CT

LAA

low attenuation area

VEGF

vascular endothelial growth factor

Larsson K. Aspects on pathophysiological mechanisms in COPD. J Intern Med. 2007;262(3):311-340. [CrossRef] [PubMed]
 
Hogg JC, Chu F, Utokaparch S, et al. The nature of small-airway obstruction in chronic obstructive pulmonary disease. N Engl J Med. 2004;350(26):2645-2653. [CrossRef] [PubMed]
 
Yoshida T, Tuder RM. Pathobiology of cigarette smoke-induced chronic obstructive pulmonary disease. Physiol Rev. 2007;87(3):1047-1082. [CrossRef] [PubMed]
 
Stoker M, Gherardi E, Perryman M, Gray J. Scatter factor is a fibroblast-derived modulator of epithelial cell mobility. Nature. 1987;327(6119):239-242. [CrossRef] [PubMed]
 
Chess PR, Ryan RM, Finkelstein JN. H441 pulmonary epithelial cell mitogenic effects and signaling pathways in response to HGF and TGF-alpha. Exp Lung Res. 1998;24(1):27-39. [CrossRef] [PubMed]
 
Hegab AE, Kubo H, Yamaya M, et al. Intranasal HGF administration ameliorates the physiologic and morphologic changes in lung emphysema. Mol Ther. 2008;16(8):1417-1426. [CrossRef] [PubMed]
 
Gazdhar A, Fachinger P, van Leer C, et al. Gene transfer of hepatocyte growth factor by electroporation reduces bleomycin-induced lung fibrosis. Am J Physiol Lung Cell Mol Physiol. 2007;292(2):L529-L536. [CrossRef] [PubMed]
 
Aoki M, Morishita R, Taniyama Y, Kaneda Y, Ogihara T. Therapeutic angiogenesis induced by hepatocyte growth factor: potential gene therapy for ischemic diseases. J Atheroscler Thromb. 2000;7(2):71-76. [CrossRef] [PubMed]
 
Tomita N, Morishita R, Taniyama Y, et al. Angiogenic property of hepatocyte growth factor is dependent on upregulation of essential transcription factor for angiogenesis, ets-1. Circulation. 2003;107(10):1411-1417. [CrossRef] [PubMed]
 
Morishita R, Makino H, Aoki M, et al. Phase I/IIa clinical trial of therapeutic angiogenesis using hepatocyte growth factor gene transfer to treat critical limb ischemia. Arterioscler Thromb Vasc Biol. 2011;31(3):713-720. [CrossRef] [PubMed]
 
Neufeld G, Cohen T, Gengrinovitch S, Poltorak Z. Vascular endothelial growth factor (VEGF) and its receptors. FASEB J. 1999;13(1):9-22. [PubMed]
 
Kasahara Y, Tuder RM, Cool CD, Lynch DA, Flores SC, Voelkel NF. Endothelial cell death and decreased expression of vascular endothelial growth factor and vascular endothelial growth factor receptor 2 in emphysema. Am J Respir Crit Care Med. 2001;163(3 pt 1):737-744. [CrossRef] [PubMed]
 
Kanazawa H, Asai K, Hirata K, Yoshikawa J. Possible effects of vascular endothelial growth factor in the pathogenesis of chronic obstructive pulmonary disease. Am J Med. 2003;114(5):354-358. [CrossRef] [PubMed]
 
Kodama T, Kanazawa H, Tochino Y, Kyoh S, Asai K, Hirata K. A technological advance comparing epithelial lining fluid from different regions of the lung in smokers. Respir Med. 2009;103(1):35-40. [CrossRef] [PubMed]
 
Vestbo J, Hurd SS, Agustí AG, et al. Global strategy for the diagnosis, management, and prevention of chronic obstructive pulmonary disease: GOLD executive summary. Am J Respir Crit Care Med. 2013;187(4):347-365. [CrossRef] [PubMed]
 
Kanazawa H, Kodama T, Asai K, Matsumura S, Hirata K. Increased levels of N(ε)-(carboxymethyl)lysine in epithelial lining fluid from peripheral airways in patients with chronic obstructive pulmonary disease: a pilot study. Clin Sci (Lond). 2010;119(3):143-149. [PubMed]
 
Kanazawa H, Tochino Y, Asai K, Ichimaru Y, Watanabe T, Hirata K. Validity of HMGB1 measurement in epithelial lining fluid in patients with COPD. Eur J Clin Invest. 2012;42(4):419-426. [CrossRef] [PubMed]
 
Ishizaka A, Watanabe M, Yamashita T, et al. New bronchoscopic microsample probe to measure the biochemical constituents in epithelial lining fluid of patients with acute respiratory distress syndrome. Crit Care Med. 2001;29(4):896-898. [CrossRef] [PubMed]
 
Ishizaka A, Matsuda T, Albertine KH, et al. Elevation of KL-6, a lung epithelial cell marker, in plasma and epithelial lining fluid in acute respiratory distress syndrome. Am J Physiol Lung Cell Mol Physiol. 2004;286(6):L1088-L1094. [CrossRef] [PubMed]
 
Nakano Y, Tasaka S, Saito F, et al. Endothelin-1 level in epithelial lining fluid of patients with acute respiratory distress syndrome. Respirology. 2007;12(5):740-743. [CrossRef] [PubMed]
 
Goddard PR, Nicholson EM, Laszlo G, Watt I. Computed tomography in pulmonary emphysema. Clin Radiol. 1982;33(4):379-387. [CrossRef] [PubMed]
 
Salgia R. Role of c-Met in cancer: emphasis on lung cancer. Semin Oncol. 2009;36(2)(suppl 1):S52-S58. [CrossRef] [PubMed]
 
Plantier L, Marchand-Adam S, Marchal-Sommé J, et al. Defect of hepatocyte growth factor production by fibroblasts in human pulmonary emphysema. Am J Physiol Lung Cell Mol Physiol. 2005;288(4):L641-L647. [CrossRef] [PubMed]
 
Vivekananda J, Awasthi V, Awasthi S, Smith DB, King RJ. Hepatocyte growth factor is elevated in chronic lung injury and inhibits surfactant metabolism. Am J Physiol Lung Cell Mol Physiol. 2000;278(2):L382-L392. [PubMed]
 
Koyama S, Sato E, Haniuda M, Numanami H, Nagai S, Izumi T. Decreased level of vascular endothelial growth factor in bronchoalveolar lavage fluid of normal smokers and patients with pulmonary fibrosis. Am J Respir Crit Care Med. 2002;166(3):382-385. [CrossRef] [PubMed]
 
Kanazawa H, Yoshikawa J. Elevated oxidative stress and reciprocal reduction of vascular endothelial growth factor levels with severity of COPD. Chest. 2005;128(5):3191-3197. [CrossRef] [PubMed]
 
Comer DM, Kidney JC, Ennis M, Elborn JS. Airway epithelial cell apoptosis and inflammation in COPD, smokers and nonsmokers. Eur Respir J. 2013;41(5):1058-1067. [CrossRef] [PubMed]
 
Aoshiba K, Yokohori N, Nagai A. Alveolar wall apoptosis causes lung destruction and emphysematous changes. Am J Respir Cell Mol Biol. 2003;28(5):555-562. [CrossRef] [PubMed]
 
Togo S, Sugiura H, Nelson A, et al. Hepatic growth factor (HGF) inhibits cigarette smoke extract induced apoptosis in human bronchial epithelial cells. Exp Cell Res. 2010;316(20):3501-3511. [CrossRef] [PubMed]
 
Chang L, Karin M. Mammalian MAP kinase signalling cascades. Nature. 2001;410(6824):37-40. [CrossRef] [PubMed]
 
Chang CC, Chiu JJ, Chen SL, et al. Activation of HGF/c-Met signaling by ultrafine carbon particles and its contribution to alveolar type II cell proliferation. Am J Physiol Lung Cell Mol Physiol. 2012;302(8):L755-L763. [CrossRef] [PubMed]
 
Chen JT, Lin TS, Chow KC, et al. Cigarette smoking induces overexpression of hepatocyte growth factor in type II pneumocytes and lung cancer cells. Am J Respir Cell Mol Biol. 2006;34(3):264-273. [CrossRef] [PubMed]
 
Nakanishi K, Takeda Y, Tetsumoto S, et al. Involvement of endothelial apoptosis underlying chronic obstructive pulmonary disease-like phenotype in adiponectin-null mice: implications for therapy. Am J Respir Crit Care Med. 2011;183(9):1164-1175. [CrossRef] [PubMed]
 
Gordon C, Gudi K, Krause A, et al. Circulating endothelial microparticles as a measure of early lung destruction in cigarette smokers. Am J Respir Crit Care Med. 2011;184(2):224-232. [CrossRef] [PubMed]
 
Kasahara Y, Tuder RM, Taraseviciene-Stewart L, et al. Inhibition of VEGF receptors causes lung cell apoptosis and emphysema. J Clin Invest. 2000;106(11):1311-1319. [CrossRef] [PubMed]
 
Kanazawa H. Role of vascular endothelial growth factor in the pathogenesis of chronic obstructive pulmonary disease. Med Sci Monit. 2007;13(11):RA189-RA195. [PubMed]
 

Figures

Figure Jump LinkFigure 1 –  Comparisons of HGF levels in epithelial lining fluid from central or peripheral airways in never smokers, smokers without COPD, and smokers with COPD. Each bar represents the median value. *P < .01 compared with central airways from never smokers. ‡P < .01 compared with central airways from smokers without COPD. #P < .01 compared with central airways from smokers with COPD. HGF = hepatocyte growth factor.Grahic Jump Location
Figure Jump LinkFigure 2 –  Comparisons of VEGF levels in epithelial lining fluid from central or peripheral airways in never smokers, smokers without COPD, and smokers with COPD. Each bar represents the median value. *P < .01 compared with central airways from never smokers. ‡P < .01 compared with central airways from smokers without COPD. VEGF = vascular endothelial growth factor.Grahic Jump Location
Figure Jump LinkFigure 3 –  Correlations between HGF and VEGF levels in epithelial lining fluid from central airways and the grade of LAA in smokers with COPD. A, HGF. B, VEGF. LAA = low attenuation area; N.S. = not significant. See Figure 1 and 2 legends for expansion of other abbreviations.Grahic Jump Location
Figure Jump LinkFigure 4 –  Correlations between HGF and VEGF levels in epithelial lining fluid from peripheral airways and the grade of LAA in smokers with COPD. See Figure 1, 2, and 3 legends for expansion of abbreviations.Grahic Jump Location
Figure Jump LinkFigure 5 –  Distribution of HGF and VEGF levels in smokers with and without COPD. ○ = smokers without COPD; ● = smokers with COPD. See Figure 1 and 2 legends for expansion of abbreviations.Grahic Jump Location

Tables

Table Graphic Jump Location
TABLE 1 ]  Clinical Characteristics of Study Subjects

All values are presented as median (interquartile range) unless otherwise noted. Dlco = diffusing capacity of the lung for carbon monoxide.

a 

P < .01 compared with never smokers.

b 

P < .01 compared with smokers without COPD.

c 

P < .05 compared with never smokers.

Table Graphic Jump Location
TABLE 2 ]  Association Between HGF and VEGF Levels in ELF of Peripheral Airways and Pulmonary Function Parameters in Smokers With COPD

ELF = epithelial lining fluid; HGF = hepatocyte growth factor; VEGF = vascular endothelial growth factor. See Table 1 legend for expansion of other abbreviation.

References

Larsson K. Aspects on pathophysiological mechanisms in COPD. J Intern Med. 2007;262(3):311-340. [CrossRef] [PubMed]
 
Hogg JC, Chu F, Utokaparch S, et al. The nature of small-airway obstruction in chronic obstructive pulmonary disease. N Engl J Med. 2004;350(26):2645-2653. [CrossRef] [PubMed]
 
Yoshida T, Tuder RM. Pathobiology of cigarette smoke-induced chronic obstructive pulmonary disease. Physiol Rev. 2007;87(3):1047-1082. [CrossRef] [PubMed]
 
Stoker M, Gherardi E, Perryman M, Gray J. Scatter factor is a fibroblast-derived modulator of epithelial cell mobility. Nature. 1987;327(6119):239-242. [CrossRef] [PubMed]
 
Chess PR, Ryan RM, Finkelstein JN. H441 pulmonary epithelial cell mitogenic effects and signaling pathways in response to HGF and TGF-alpha. Exp Lung Res. 1998;24(1):27-39. [CrossRef] [PubMed]
 
Hegab AE, Kubo H, Yamaya M, et al. Intranasal HGF administration ameliorates the physiologic and morphologic changes in lung emphysema. Mol Ther. 2008;16(8):1417-1426. [CrossRef] [PubMed]
 
Gazdhar A, Fachinger P, van Leer C, et al. Gene transfer of hepatocyte growth factor by electroporation reduces bleomycin-induced lung fibrosis. Am J Physiol Lung Cell Mol Physiol. 2007;292(2):L529-L536. [CrossRef] [PubMed]
 
Aoki M, Morishita R, Taniyama Y, Kaneda Y, Ogihara T. Therapeutic angiogenesis induced by hepatocyte growth factor: potential gene therapy for ischemic diseases. J Atheroscler Thromb. 2000;7(2):71-76. [CrossRef] [PubMed]
 
Tomita N, Morishita R, Taniyama Y, et al. Angiogenic property of hepatocyte growth factor is dependent on upregulation of essential transcription factor for angiogenesis, ets-1. Circulation. 2003;107(10):1411-1417. [CrossRef] [PubMed]
 
Morishita R, Makino H, Aoki M, et al. Phase I/IIa clinical trial of therapeutic angiogenesis using hepatocyte growth factor gene transfer to treat critical limb ischemia. Arterioscler Thromb Vasc Biol. 2011;31(3):713-720. [CrossRef] [PubMed]
 
Neufeld G, Cohen T, Gengrinovitch S, Poltorak Z. Vascular endothelial growth factor (VEGF) and its receptors. FASEB J. 1999;13(1):9-22. [PubMed]
 
Kasahara Y, Tuder RM, Cool CD, Lynch DA, Flores SC, Voelkel NF. Endothelial cell death and decreased expression of vascular endothelial growth factor and vascular endothelial growth factor receptor 2 in emphysema. Am J Respir Crit Care Med. 2001;163(3 pt 1):737-744. [CrossRef] [PubMed]
 
Kanazawa H, Asai K, Hirata K, Yoshikawa J. Possible effects of vascular endothelial growth factor in the pathogenesis of chronic obstructive pulmonary disease. Am J Med. 2003;114(5):354-358. [CrossRef] [PubMed]
 
Kodama T, Kanazawa H, Tochino Y, Kyoh S, Asai K, Hirata K. A technological advance comparing epithelial lining fluid from different regions of the lung in smokers. Respir Med. 2009;103(1):35-40. [CrossRef] [PubMed]
 
Vestbo J, Hurd SS, Agustí AG, et al. Global strategy for the diagnosis, management, and prevention of chronic obstructive pulmonary disease: GOLD executive summary. Am J Respir Crit Care Med. 2013;187(4):347-365. [CrossRef] [PubMed]
 
Kanazawa H, Kodama T, Asai K, Matsumura S, Hirata K. Increased levels of N(ε)-(carboxymethyl)lysine in epithelial lining fluid from peripheral airways in patients with chronic obstructive pulmonary disease: a pilot study. Clin Sci (Lond). 2010;119(3):143-149. [PubMed]
 
Kanazawa H, Tochino Y, Asai K, Ichimaru Y, Watanabe T, Hirata K. Validity of HMGB1 measurement in epithelial lining fluid in patients with COPD. Eur J Clin Invest. 2012;42(4):419-426. [CrossRef] [PubMed]
 
Ishizaka A, Watanabe M, Yamashita T, et al. New bronchoscopic microsample probe to measure the biochemical constituents in epithelial lining fluid of patients with acute respiratory distress syndrome. Crit Care Med. 2001;29(4):896-898. [CrossRef] [PubMed]
 
Ishizaka A, Matsuda T, Albertine KH, et al. Elevation of KL-6, a lung epithelial cell marker, in plasma and epithelial lining fluid in acute respiratory distress syndrome. Am J Physiol Lung Cell Mol Physiol. 2004;286(6):L1088-L1094. [CrossRef] [PubMed]
 
Nakano Y, Tasaka S, Saito F, et al. Endothelin-1 level in epithelial lining fluid of patients with acute respiratory distress syndrome. Respirology. 2007;12(5):740-743. [CrossRef] [PubMed]
 
Goddard PR, Nicholson EM, Laszlo G, Watt I. Computed tomography in pulmonary emphysema. Clin Radiol. 1982;33(4):379-387. [CrossRef] [PubMed]
 
Salgia R. Role of c-Met in cancer: emphasis on lung cancer. Semin Oncol. 2009;36(2)(suppl 1):S52-S58. [CrossRef] [PubMed]
 
Plantier L, Marchand-Adam S, Marchal-Sommé J, et al. Defect of hepatocyte growth factor production by fibroblasts in human pulmonary emphysema. Am J Physiol Lung Cell Mol Physiol. 2005;288(4):L641-L647. [CrossRef] [PubMed]
 
Vivekananda J, Awasthi V, Awasthi S, Smith DB, King RJ. Hepatocyte growth factor is elevated in chronic lung injury and inhibits surfactant metabolism. Am J Physiol Lung Cell Mol Physiol. 2000;278(2):L382-L392. [PubMed]
 
Koyama S, Sato E, Haniuda M, Numanami H, Nagai S, Izumi T. Decreased level of vascular endothelial growth factor in bronchoalveolar lavage fluid of normal smokers and patients with pulmonary fibrosis. Am J Respir Crit Care Med. 2002;166(3):382-385. [CrossRef] [PubMed]
 
Kanazawa H, Yoshikawa J. Elevated oxidative stress and reciprocal reduction of vascular endothelial growth factor levels with severity of COPD. Chest. 2005;128(5):3191-3197. [CrossRef] [PubMed]
 
Comer DM, Kidney JC, Ennis M, Elborn JS. Airway epithelial cell apoptosis and inflammation in COPD, smokers and nonsmokers. Eur Respir J. 2013;41(5):1058-1067. [CrossRef] [PubMed]
 
Aoshiba K, Yokohori N, Nagai A. Alveolar wall apoptosis causes lung destruction and emphysematous changes. Am J Respir Cell Mol Biol. 2003;28(5):555-562. [CrossRef] [PubMed]
 
Togo S, Sugiura H, Nelson A, et al. Hepatic growth factor (HGF) inhibits cigarette smoke extract induced apoptosis in human bronchial epithelial cells. Exp Cell Res. 2010;316(20):3501-3511. [CrossRef] [PubMed]
 
Chang L, Karin M. Mammalian MAP kinase signalling cascades. Nature. 2001;410(6824):37-40. [CrossRef] [PubMed]
 
Chang CC, Chiu JJ, Chen SL, et al. Activation of HGF/c-Met signaling by ultrafine carbon particles and its contribution to alveolar type II cell proliferation. Am J Physiol Lung Cell Mol Physiol. 2012;302(8):L755-L763. [CrossRef] [PubMed]
 
Chen JT, Lin TS, Chow KC, et al. Cigarette smoking induces overexpression of hepatocyte growth factor in type II pneumocytes and lung cancer cells. Am J Respir Cell Mol Biol. 2006;34(3):264-273. [CrossRef] [PubMed]
 
Nakanishi K, Takeda Y, Tetsumoto S, et al. Involvement of endothelial apoptosis underlying chronic obstructive pulmonary disease-like phenotype in adiponectin-null mice: implications for therapy. Am J Respir Crit Care Med. 2011;183(9):1164-1175. [CrossRef] [PubMed]
 
Gordon C, Gudi K, Krause A, et al. Circulating endothelial microparticles as a measure of early lung destruction in cigarette smokers. Am J Respir Crit Care Med. 2011;184(2):224-232. [CrossRef] [PubMed]
 
Kasahara Y, Tuder RM, Taraseviciene-Stewart L, et al. Inhibition of VEGF receptors causes lung cell apoptosis and emphysema. J Clin Invest. 2000;106(11):1311-1319. [CrossRef] [PubMed]
 
Kanazawa H. Role of vascular endothelial growth factor in the pathogenesis of chronic obstructive pulmonary disease. Med Sci Monit. 2007;13(11):RA189-RA195. [PubMed]
 
NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Find Similar Articles
CHEST Journal Articles
PubMed Articles
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543