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Genetic variation and epigenetic factors are thought to contribute to the development of hypersensitivity to aspirin. DNA methylation fluctuates dynamically throughout the day. To discover new CpG methylation in lymphocytes associated with aspirin-exacerbated respiratory disease (AERD), we evaluated changes in global CpG methylation profiles from before to after an oral aspirin challenge in patients with AERD and aspirin-tolerant asthma (ATA). Whole-genome CpG methylation levels of peripheral blood mononuclear cells were quantified with an Illumina 860K Infinium Methylation EPIC BeadChip array and then adjusted for inferred lymphocyte fraction (ILF) with GLINT and Tensor Composition Analysis. Among the 866,091 CpGs in the array, differentially methylated CpGs (DMCs) were found in 6 CpGs in samples from all 12 patients with asthma included in the study (AERD, n = 6; ATA, n = 6). DMCs were found in 3 CpGs in the 6 ATA samples and in 615 CpGs in the 6 AERD samples. A total of 663 DMCs in 415 genes and 214 intergenic regions differed significantly in the AERD compared with the ATA. In promoters, 126 CpG loci were predicted to bind to 38 transcription factors (TFs), many of which were factors already known to be involved in the pathogenesis of asthma and immune responses. In conclusion, we identified 615 new CpGs methylated in peripheral blood lymphocytes by oral aspirin challenge in AERD but not in ATA. These findings indicate that oral aspirin challenge induces epigenetic changes in ILFs, specifically in AERD patients, possibly via changes in TF binding, which may have epigenetic effects on the development of AERD. [ABSTRACT FROM AUTHOR]

Purpose Melanocortin 3 Receptor (MC3R) is one of the families of seven-transmembrane G-protein-coupled receptors, and a recent study showed that MCR3 promoter polymorphism was significantly associated with the susceptibility of tuberculosis (TB) in South African population. Methods We analyzed six MC3R polymorphisms to examine the genetic effects on the risk of pulmonary TB in Korean subjects by using TaqMan assays and case-control analyses. Results Using statistical analyses, one common promoter polymorphism (MC3Rrs11575886 T > C) was found to be associated with an increased risk of pulmonary TB. The frequency of the C-bearing genotype of rs11575886 was higher in pulmonary TB patients than in normal controls (p = 0.03, OR = 1.46) although the significance was not retained after correction. In silico analysis for the difference of transcription binding factor (TF), motif between C and T allele demonstrated that the TF motif and its threshold scores of C allele were lower than those of T allele. Conclusions The C allele of rs11575886 could be a risk allele for the pulmonary TB by affecting the binding of TF. Our findings suggest that polymorphisms in MC3R might be one of genetic factors for the risk of pulmonary TB development in Korean subjects. Electronic supplementary material The online version of this article (doi:10.1007/s00408-014-9625-2) contains supplementary material, which is available to authorized users., Author(s): Byung Lae Park[sup.1] , Lyoung Hyo Kim[sup.1] [sup.2] , Suhg Namgoong[sup.1] [sup.2] , Ji On Kim[sup.1] [sup.2] , Jason Yongha Kim[sup.2] , Hun Soo Chang[sup.3] [sup.4] [sup.5] , Jong [...]

Background Idiopathic pulmonary fibrosis (IPF) is characterized by progressive dyspnea and worsening lung function due to remodeling of the lung, including epithelial mesenchymal transition. ADAM33 is a disintegrin and metalloprotease domain-containing protein, which may be related to lung fibrosis by exerting angiogenesis and remodeling of the lung. Thus, we evaluated the association of single-nucleotide polymorphisms (SNPs) of ADAM33 with the risk of IPF. Methods A total of 237 patients with IPF and 183 healthy subjects participated in the present study. Nine polymorphisms were selected. Genotyping was performed by single-base extension. Polymorphisms and haplotypes were analyzed for associations with the risk of IPF using multiple logistic regression models controlling for age, gender, and smoking status as covariates. Results All SNPs were in Hardy-Weinberg equilibrium. The minor allele frequency (MAF) of rs628977G>A in intron 21 was significantly lower in subjects with surgical IPF than in normal controls in the recessive model [33.2 vs. 38.0 %, p = 0.02, OR = 0.40 (0.19-0.84)]. When the subjects with clinical IPF were included, the difference in MAF persisted with a p value of 0.03 [OR = 0.50 (0.27-0.94)]. Conclusions ADAM33 rs628977G>A was marginally associated with a decreased risk of IPF in a recessive model., Author(s): Soo-Taek Uh[sup.1] , An-Soo Jang[sup.2] , Sung-Woo Park[sup.2] , Jong-Sook Park[sup.2] , Chang-Gi Min[sup.2] , Yong Hoon Kim[sup.3] , Byung-Lae Park[sup.4] , Hyoung Doo Shin[sup.4] [sup.5] , Dong Soon [...]

Background Idiopathic pulmonary fibrosis (IPF) is characterized by progressive dyspnea and worsening lung function. ACE is increased in the bronchoalveolar lavage fluid from patients with IPF, suggesting the role of ACE in the pathogenesis of IPF. We evaluated the role of single-nucleotide polymorphisms (SNPs) in the development risk of IPF. Methods Two-hundred twenty patients with IPF and 456 healthy subjects were included in this study. Eleven polymorphisms were selected among those reported previously. Genotype was performed by single base extension. Results Although absolute LD ([absolute value of D'] = 1 and r = 1) was not present, 11 SNPs showed tight LDs. The logistic analysis of the all of 11 SNPs on the ACE genes between patients with IPF and healthy subjects were found to be related with the risk of IPF in recessive type. However, in patients with IPF diagnosed by surgical lung biopsy, only two SNP of -5538T>C and +21288_insdel SNPs were related with the risk of IPF in co-dominant type, and there were no SNPs related with the risk of IPF in dominant type. In patients with IPF diagnosed by clinical criteria or surgical lung biopsy, four SNPs on promoter (-5538T>C, -5508A>C, -3927T>C, -115T>C), one on intron (+15276A>G), one on exon (+21181G>A), and one in three prime region (+21288_insdel) were related with the risk of IPF. Conclusions This study showed a newly discovered SNP of ACE associated with the risk of development of IPF. ACE -5538T>C and -5508A>C significantly associated with risk of IPF in Korea. Keywords Angiotensin-converting enzyme * Genetic polymorphism * Genotype * Pulmonary fibrosis * SNPs, Introduction Idiopathic pulmonary fibrosis (IPF) is a devastating disease belonging to the idiopathic interstitial pneumonia family. It is characterized by progressive dyspnea and worsening lung function [1]. Although the pathogenesis [...]

Background Refractory asthma, a subtype of asthma with uncontrolled symptoms despite antiasthma medications, is a heterogeneous syndrome with variable clinical features, presumably different etiologies, and pathophysiological mechanisms. The heterogeneity of refractory asthma, however, is poorly understood. We aimed to characterize refractory asthma and to improve our understanding of the heterogeneity of refractory asthma patients. Methods We identified refractory asthma patients (n = 96) as defined by the American Thoracic Society's criteria from a cohort of Korean asthma patients (n = 2,187). Then, cluster analysis was conducted to classify subtypes of refractory asthma. Results Among the study group, 4.4% (n = 96) of all asthma patients had refractory asthma. Cluster analysis identified four distinct groups of refractory asthma. Age at onset was younger in clusters 1 and 2 than in clusters 3 and 4. Patients in cluster 1 had the most well-preserved pulmonary function; patients in cluster 2 had a female predominance and the most severe airway obstruction; patients in cluster 3 were mostly female and had the most enhanced bronchial hyperresponsiveness; and patients in cluster 4 were most male and tended to be cigarette smokers. Conclusions The current results suggest that refractory asthma is a heterogeneous syndrome and could be classified into four subtypes. Underlying pathogenesis and therapeutic approaches may differ for the different subtypes and further research is needed. Keywords Asthma * Cluster analysis * Airway obstruction * Bronchial hyperreactivity, Introduction More than 90% of asthma patients can successfully manage their asthma with an inhaled corticosteroid (ICS). Despite the success of this therapy, patients with refractory asthma continue to suffer [...]