A Genome-Wide Association Study in Early COPD: Identification of One Major Susceptibility Loci.

Background: Identifying the genetic basis of airflow limitation is one of the most interesting issues for understanding chronic obstructive pulmonary disease (COPD) pathophysiology. Several studies have shown that some genetic variants associated with COPD have been identified in genome-wide association study (GWAS), especially in patients with moderate to severe COPD; genetic susceptibility for airflow limitation in the early COPD phase has not been widely studied. Objective: We investigated the genetic variants in early COPD. Methods: The present study analyzed Gene-environment interaction and phenotype (GENIE) cohort that included participants who received health screening examination. The association between single nucleotide polymorphism (SNP) and susceptibility to early COPD (FEV1 predicted ≥50% and FEV1/FVC <0.7) was tested. Results: A total of 130 patients with early COPD and 3478 controls (1700 ever smokers and 1778 never smokers) were recruited. When compared with the total controls, certain SNPs (rs2818103, rs875033, rs9354627, rs34552148) on chromosome 6 were included at the top of our list (p= 5.6 × 10-7 ~9.6 × 10-6) although they did not reach genome-wide significance. When compared with the never smoker controls, two SNPs (rs2857210, rs2621419) of the HLA-DQB2 gene class were persistently associated with susceptibility to early COPD. Conclusion: Certain SNPs located on chromosome 6 or the HLA-DQB2 gene were the top-scoring SNPs for the association with susceptibility to early COPD in the Korean GENIE cohort.

Association between body composition and pulmonary function in elderly people: the Korean Longitudinal Study on Health and Aging.

The age-related increase in body fat and decrease in muscle mass are associated with increased morbidity in elderly populations. Pulmonary function also decreases with age, but no study has investigated whether regional body composition is associated with pulmonary function in an older population. The Korean Longitudinal Study on Health and Aging is a community-based cohort study of people aged > 65 years selected by random stratified sampling. Anthropometrics, biochemical factors, and lung function by spirometry were evaluated in 439 men (mean age of 75.9 ± 8.6 years) and 561 women (mean age of 76.0 ± 8.8 years). Dual-energy X-ray absorptiometry (DXA) was performed to assess the whole and regional body composition. Computed tomography (CT) was also used to measure fat or muscle distribution at the abdominal and mid-thigh levels. Although pulmonary function and muscle mass were inversely related to age, fat mass was not. After adjusting for age, height, BMI, smoking and exercise status, and high sensitivity C-reactive protein (hsCRP), fat mass in trunk or central area was inversely associated with lung function in both sexes (P < 0.01). Men with more muscle in trunk and mid-thigh level had better lung function (P < 0.01). The results of this community-based study show that regional body composition is significantly associated with lung function. Augmentation of muscle in the trunk and low extremity in men, and reduction of fat in the trunk and upper body in men and women may be helpful in maintaining lung function in the elderly population.

Role of C-reactive protein and procalcitonin in differentiation of tuberculosis from bacterial community acquired pneumonia.

BACKGROUND/AIMS: We investigated the utility of serum C-reactive protein (CRP) and procalcitonin (PCT) for differentiating pulmonary tuberculosis (TB) from bacterial community-acquired pneumonia (CAP) in South Korea, a country with an intermediate TB burden. METHODS: We conducted a prospective study, enrolling 87 participants with suspected CAP in a community-based referral hospital. A clinical assessment was performed before treatment, and serum CRP and PCT were measured. The test results were compared to the final diagnoses. RESULTS: Of the 87 patients, 57 had bacterial CAP and 30 had pulmonary TB. The median CRP concentration was 14.58 mg/dL (range, 0.30 to 36.61) in patients with bacterial CAP and 5.27 mg/dL (range, 0.24 to 13.22) in those with pulmonary TB (p<0.001). The median PCT level was 0.514 ng/mL (range, 0.01 to 27.75) with bacterial CAP and 0.029 ng/mL (range, 0.01 to 0.87) with pulmonary TB (p<0.001). No difference was detected in the discriminative values of CRP and PCT (p=0.733). CONCLUSIONS: The concentrations of CRP and PCT differed significantly in patients with pulmonary TB and bacterial CAP. The high sensitivity and negative predictive value for differentiating pulmonary TB from bacterial CAP suggest a supplementary role of CRP and PCT in the diagnostic exclusion of pulmonary TB from bacterial CAP in areas with an intermediate prevalence of pulmonary TB.

Chest computed tomography (CT) immediately after CT-guided transthoracic needle aspiration biopsy as a predictor of overt pneumothorax.

BACKGROUND/AIMS: This study examined the correlation between pneumothorax detected by immediate post-transthoracic needle aspiration-biopsy (TTNB) chest computed tomography (CT) and overt pneumothorax detected by chest PA, and investigated factors that might influence the correlation. METHODS: Adult patients who had undergone CT-guided TTNB for lung lesions from May 2003 to June 2007 at Seoul National University Bundang Hospital were included. Immediate post-TTNB CT and chest PA follow-up at 4 and 16 hours after CT-guided TTNB were performed in 934 patients. RESULTS: Pneumothorax detected by immediate chest CT (CT-pneumothorax) was found in 237 (25%) and overt pneumothorax was detected by chest PA follow-up in 92 (38.8%) of the 237 patients. However, overt pneumothorax was found in 18 (2.6%) of the 697 patients without CT-pneumothorax. The width and depth of CT-pneumothorax were predictive risk factors for overt pneumothorax. CONCLUSIONS: CT-pneumothorax is very sensitive for predicting overt pneumothorax, and the width and depth on CT-pneumothorax are reliable risk factors for predicting overt pneumothorax.

Impact of toxocariasis in patients with unexplained patchy pulmonary infiltrate in Korea.

Toxocariasis is one of the causes of pulmonary eosinophilic infiltrate that is increasing in Korea. This study was designed to identify the prevalence of toxocara seropositivity in patients with unexplained pulmonary patchy infiltrate and to evaluate associated factors. We evaluated 102 patients with unexplained pulmonary patchy infiltrate on chest computed tomography (CT) scan. As a control set, 116 subjects with normal chest CT were also evaluated. History of allergic disease, drug use, parasitic disease and raw cow liver intake were taken. Blood eosinophil count and total IgE level were measured. Specific serum IgG antibody to Toxocara canis larval antigen and specific IgG antibodies to 4 other parasites were measured by enzyme-linked immunosorbent assay (ELISA). In the infiltrate group, 66.7% subjects were toxocara seropositive whereas 22.4% of the control group were seropositive (p<0.001). In the infiltrate group, patients with a history of eating raw cow liver (odds ratio [OR], 7.8) and patients with eosinophilia (OR, 5.2) had a higher incidence of toxocara seropositivity. Thirty-five percent of toxocara seropositive patients with infiltrate exhibited migrating infiltrate and 48% had decreased infiltrate on the follow-up CT. We recommend that toxocara ELISA should be performed in patients with unexplained pulmonary patchy infiltrate, and that the eating of raw cow liver should be actively discouraged.

CT scanning-based phenotypes vary with ADRB2 polymorphisms in chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease that is characterized by varying degrees of involvement of airway and lung parenchyma. Although cigarette smoke is the major risk factor for COPD, the principal determining factors of involvement of the airway or lung parenchyma have not been clearly defined. Genetic variability in COPD patients might influence the varying degrees of involvement of airway and parenchyma. We therefore studied whether airway and parenchyma involvement might be associated with the ADRB2 genotype, which has been reported to be associated with COPD susceptibility and the bronchodilator response. METHODS: One hundred and eleven COPD subjects, whose post-bronchodilator FEV(1)/FVC values were less than 0.7, and who had histories of smoking exceeding 10 pack-years, were prospectively recruited from pulmonology clinics of 11 hospitals in Seoul, Korea. The degrees of involvement of airway and parenchyma were evaluated by volumetric computed tomography (CT) scans. In-house software automatically calculated luminal areas, airway wall areas, percentages of wall areas in segmental bronchi, emphysema indices, and mean lung densities in the whole lung parenchyma. The ADRB2 genotypes at codon 16 were determined for all patients. RESULTS: Gly16 was associated with lumen diameter, luminal area, and percentage of wall area in patients with COPD (p=0.02), whereas neither wall area nor wall thickness differed with ADRB2 genotype. Neither emphysema index nor mean lung density was associated with ADRB2 genotype. CONCLUSION: Gly16 variant in ADRB2 gene was associated with airway wall phenotypes measured using CT scanning in COPD patients.

Lung function response to 12-week treatment with combined inhalation of long-acting beta2 agonist and glucocorticoid according to ADRB2 polymorphism in patients with chronic obstructive pulmonary disease.

Recent reports suggest that beta(2)-adrenergic receptor (ADRB2) genotypes are associated with therapeutic responses to beta(2) agonists in asthmatics. However, few studies have investigated therapeutic responses to beta(2) agonists in chronic obstructive pulmonary disease (COPD) patients. This study investigated immediate bronchodilator response and lung function responses following a 12-week treatment with a long-acting beta(2) agonist combined with a steroid inhaler in patients with COPD with various ADRB2 genotypes. One hundred four patients with chronic obstruction were genotyped for codon 16 and 27 polymorphisms of the ADRB2 gene. The immediate bronchodilator response to beta(2)-agonist treatment was evaluated after inhalation of 400 microg salbutamol. In addition, long-term response was evaluated using observed change in spirometric values before and after the treatment with salmeterol (50 microg) combined with fluticasone propionate (500 microg) inhalation twice daily for 12 weeks. In terms of codon 16 variants, the immediate bronchodilator response to salbutamol was 6.4 +/- 0.8% (% predicted value) in Arg/Arg patients, 4.9 +/- 0.7% in Arg/Gly patients, and 5.8 +/- 1.2% in Gly/Gly patients (p = 0.418). The FEV(1) changes following the 12-week treatment were 7.0 +/- 1.2% in Arg/Arg patients, 3.0 +/- 1.5% in Arg/Gly patients, and 7.2 +/- 1.2% in Gly/Gly patients (p = 0.229). Similarly, there was no difference between codon 27 variants in terms of immediate bronchodilator response or FEV1 changes after 12 weeks of treatment. We were unable to demonstrate an association between ADRB2 genotype and the effect on lung function of 12-week treatment with combined long-acting beta(2) agonist and glucocorticoid inhalation or on the immediate bronchodilator response to a short-acting beta(2) agonist in patients with COPD.

Bronchial washing yield before and after forceps biopsy in patients with endoscopically visible lung cancers.

BACKGROUND AND OBJECTIVE: The need for routine use of bronchial washing in addition to forceps biopsy has been debated in the diagnosis of endoscopically visible lung tumours. Moreover, the optimal sequence for obtaining bronchial washing and forceps biopsy specimens from endoscopically visible tumours through a flexible bronchoscope has not been well established. METHODS: A multicentre 13-month prospective randomized study was performed. Two hundred and thirty consecutive patients with endoscopically visible tumours were randomly assigned into a bronchial washing before forceps biopsy (pre-biopsy) group and a bronchial washing after forceps biopsy (post-biopsy) group. Bronchial washing and forceps biopsy were performed according to the assigned sequence. RESULTS: Two hundred and seven patients with a definite cytological or histological diagnosis of lung cancer were included in the analyses. One hundred and three were in the pre-biopsy group and 104 were in the post-biopsy group. The diagnostic yield of bronchial washing was 57.3% (59/103) in the pre-biopsy group and 55.8% (58/104) in the post-biopsy group (P = 0.88). In addition, bronchial washing provided the diagnosis in six patients without definite diagnosis from forceps biopsy, and its addition to forceps biopsy significantly increased the overall diagnostic yield of bronchoscopy from 93.7% to 96.6% (P = 0.03). CONCLUSION: The sequence for performing bronchial washing before or after forceps biopsy did not affect the diagnostic yield of bronchial washing in patients with endoscopically visible lung cancers. However, bronchial washing led to a significant increase in the overall diagnostic yield of bronchoscopy in patients with lung cancers.

Clinical significance of a solitary ground-glass opacity (GGO) lesion of the lung detected by chest CT.

Ground-glass opacity (GGO) attracts attention because of the possibility of early lung cancer. However, some lesions are reduced in size or disappear at follow-up. This study was designed to explore the natural history of solitary GGO, to determine the prevalence of malignancy and to identify factors predictive of benignity or malignancy. Solitary and focal GGO lesions [pGGO (p=pure) and mGGO (m=mixed) based on the presence of a solid component] of less than 3 cm were included. Lesions of less than 1cm were followed up by chest HRCT 3 months later and lesions over 1cm were investigated by percutaneous needle biopsy (PCNB). One hundred and eighty-six patients (69 pGGO and 117 mGGO) were enrolled. Of the 69 pGGO lesions, 7 were diagnosed as pre-malignant or malignant lesions, 3 as benign lesions and 26 pGGO lesions (37.6%) were reduced or disappeared (transient lesions) at follow-up chest HRCT. The other 33 lesions showed no significant change during follow-up. Thus, the probability of malignancy in pGGO was 7/36 (19.4%). On the other hand, of the 117 mGGO lesions, 26 were found to be malignant, 3 were diagnosed as benign and 57 lesions (48.7%) were reduced or had disappeared at follow-up chest HRCT. The other 31 lesions showed no change during follow-up, and thus the probability of malignancy in mGGO was 26/86 (30.2%). A female sex and a spiculated mGGO border were found to be related with malignancy. However, a high blood eosinophil count was strongly associated with regressing or transient mGGO, suggesting that pulmonary infiltrate with eosinophilia (PIE) might have been responsible. We recommend short-term follow-up by chest HRCT be conducted for mGGO lesions in the presence of high eosinophilia--regardless of lesion size.

Adenovirus expressing shRNA to IGF-1R enhances the chemosensitivity of lung cancer cell lines by blocking IGF-1 pathway.

RNA interference is a phenomenon whereby small double-stranded RNA knocks down the expression of a sequence-specific gene. Double-stranded siRNA transfection, as currently used, is considered to have transient and low transfection efficiency. We constructed an adenoviral vector-based short hair-pin(sh)RNA system to overcome the limitations of the genetic blockade of IGF-1R, one of most important cancer therapy targets. We constructed three different IGF-1R specific shRNAs (612, 801, and 3425) and generated three ad-shIGF-1Rs using BD Adeno-X expression system. We assessed the effect of ad-shIGF-1R on signal transduction, induction of apoptosis, and in vitro tumorigenicity of lung cancer cell lines. Western blot and FACS assays demonstrated that endogenous IGF-1R expression was efficiently suppressed after transduction of lung cancer cell lines with the three different ad-shIGF-1Rs. IGF-1R blockade by ad-shIGF-1R inhibited ligand induced phosphorylation of pAkt and pErk, and ad-shIGF-1R effectively blocked the in vitro tumorigenicity of lung cancer cell lines. Moreover, the transduction of a human lung cancer cell line with ad-IGF-1R(3425) enhanced chemosensitivity to anticancer drugs. We conclude that the adenoviral vector-based approach to the RNA interference of IGF-1R induced effective IGF-1R silencing in lung cancer cell lines as manifested by effective blocking of the downstream pathway of IGF-1R and by an antitumor effect. We believe that this system can be usefully applied to other cancer targets.

The prevalence of pulmonary parenchymal tuberculosis in patients with tuberculous pleuritis.

STUDY OBJECTIVE: To examine the prevalence and characteristics of parenchymal tuberculous pleuritis in adult patients. DESIGN: Prospective cohort study. SETTING: Three hospitals affiliated with Seoul National University in South Korea. PATIENTS: All patients > 15 years old with a diagnosis of tuberculous pleuritis were enrolled prospectively between January 1, 2004, and October 31, 2004. INTERVENTIONS: Diagnostic thoracocentesis and CT of the chest were done for each patient. Acid-fast bacilli (AFB) smears and cultures for Mycobacterium tuberculosis were requested if patients produced any sputum. A board-certified radiologist reviewed the chest radiographs for the presence and characteristics of any lesions. MEASUREMENTS AND RESULTS: One hundred six patients with tuberculous pleuritis were enrolled (median age, 53 years; range 16 to 89 years). Among them, 33 patients (31%) had sputum or bronchial washing findings positive for AFB smears or for M tuberculosis by culture. Lung parenchymal lesions were observed in 91 of the patients (86%) using chest CT; 39 patients (37%) with parenchymal lesions had radiographic characteristics of active pulmonary tuberculosis. In total, 62 patients (59%) had bacteriologically or radiographically active pulmonary tuberculosis. In addition, 78 patients (74%) had features of reactivated pulmonary tuberculosis. CONCLUSIONS: Lung parenchymal lesions were more common in this series of patients with tuberculous pleuritis than has been reported in previous studies. The patients mostly had radiographic features of reactivated, rather than primary, tuberculosis.

In vivo imaging of adenovirus transduction and enhanced therapeutic efficacy of combination therapy with conditionally replicating adenovirus and adenovirus-p27.

Gene therapy is hampered by poor gene transfer to the tumor mass. We previously proposed a combination adenoviral gene therapy containing a conditionally replicating adenovirus (CRAD) expressing mutant E1 (delta24RGD) and a replication-defective E1-deleted adenovirus to enhance the efficiency of gene transfer. Mutant E1 expressed by delta24RGD enables the replication of replication-defective adenoviruses in tumors when cancer cells are co-infected with both viruses. In this study, gene transfer rates in xenografts tumors were monitored by bioluminescence in cells infected with the replication-defective adenovirus-luciferase (ad-luc). Tumor masses treated with CRAD + ad-luc showed dramatically stronger and more prolonged luciferase expression than ad-luc-treated tumors and this expression spread through the entire tumor mass without significant systemic spread. Transduction with CRAD + replication-defective adenovirus-p27 increased the expression of p27 by 24-fold versus transduction with ad-p27 alone. Treatment of a lung cancer cell line and of established lung cancer xenografts with CRAD + adenovirus-p27 also induced stronger growth suppression than treatment with either virus alone. These findings confirm the selective replication of E1-deleted adenovirus containing a therapeutic gene due to the presence of mutant E1 produced by delta24RGD in tumors. Moreover, this replication increased the therapeutic gene transfer rate and enhanced its antitumor effects.

Association of HLA-DR and HLA-DQ genes with susceptibility to pulmonary tuberculosis in Koreans: preliminary evidence of associations with drug resistance, disease severity, and disease recurrence.

Only 10% of persons infected with Mycobacterium tuberculosis develop clinical tuberculosis (TB), indicating the existence of host genetic factors regulating disease expression. We investigated the association of human leukocyte antigen (HLA) class II genes with the susceptibility to pulmonary TB in Koreans, with special emphasis on their association with drug resistance, disease severity, and disease recurrence. Human leukocyte antigens (HLA)-DRB1 and -DQB1 gene polymorphisms were analyzed in 160 Korean patients with pulmonary TB and 200 ethnically matched healthy controls. HLA-DRB1*0803 (25.0% vs. 14.5% in controls, OR = 1.97, p = 0.012, corrected p (p(c)) > 0.05) and DQB1*0601 (27.5% vs. 15.5% in controls, OR = 2.07, p = 0.005, p(c) > 0.05) were weakly associated with general susceptibility to TB. DRB1*0803 was significantly associated with drug resistance (30.9% vs. 14.5%, OR = 2.63, p(c) = 0.047) and more advanced lung lesion (29.8% vs. 14.5%, OR = 2.50, p(c) = 0.022). DRB1*0803 showed the strongest association with disease recurrence, especially after curative treatment for the earlier infection (47.4% vs. 14.5%, OR = 5.31, p(c) = 0.00009). DQB1*0601, which is strongly linked to DRB1*0803 in this population showed similar changes in the patients as those of DRB1*0803. It is suggested that DRB1*0803 and DQB1*0601 alleles are associated with disease progression of TB in Koreans, exerting influence on the development of drug resistance, severe disease, and recurrent disease.

Gene therapy with GM-CSF, interleukin-4 and herpes simplex virus thymidine kinase shows strong antitumor effect on lung cancer.

BACKGROUND: Inadequate release of tumor antigens (TA) and a defective antigen presentation by dendritic cells (DC) are the major mechanisms for how tumor cells can escape the host immune surveillance. MATERIALS AND METHODS: Combined gene therapy of herpes simplex virus thymidine kinase (Tk), GM-CSF and IL-4 via adenoviral vector was tested to solve these problems. After establishing wild-type Lewis lung carcinoma (LLC), vaccinations with LLC transduced with Tk +/- GM-CSF +/- IL-4 were performed. RESULTS: The LLC-Tk and LLC-Tk-IL-4 vaccination groups failed to suppress the wild-type LLC growth. However, the LLC-Tk-GM-CSF group showed a delayed wild-type tumor growth and LLC-Tk-GM-CSF-IL-4 markedly suppressed tumor growth and increased the survival rate of mice. Immunohistochemistry of the spleen showed a dense infiltration of DCs in the mice treated with LLC-Tk-GM-CSF-IL-4. CONCLUSION: Combined gene therapy with Tk-GM-CSF-IL-4 was effective in inducing antitumor immunity by enhancing the DC functions.