Gender Differences in Plasma Biomarker Levels in a Cohort of COPD Patients: A Pilot Study

Little is known about gender differences in plasma biomarker levels in patients with chronic obstructive pulmonary disease (COPD). HYPOTHESIS: There are differences in serum biomarker levels between women and men with COPD. OBJECTIVE: Explore gender differences in plasma biomarker levels in patients with COPD and smokers without COPD. METHODS: We measured plasma levels of IL-6, IL-8, IL-16, MCP-1, MMP-9, PARC and VEGF in 80 smokers without COPD (40 males, 40 females) and 152 stable COPD patients (76 males, 76 females) with similar airflow obstruction. We determined anthropometrics, smoking history, lung function, exercise tolerance, body composition, BODE index, co-morbidities and quality of life. We then explored associations between plasma biomarkers levels and the clinical characteristics of the patients and also with the clinical and physiological variables known to predict outcome in COPD. RESULTS: The plasma biomarkers level explored were similar in men and women without COPD. In contrast, in patients with COPD the median value in pg/mL of IL-6 (6.26 vs 8.0, p = 0.03), IL-16 (390 vs 321, p = 0.009) and VEGF (50 vs 87, p = 0.02) differed between women and men. Adjusted for smoking history, gender was independently associated with IL-16, PARC and VEGF levels. There were also gender differences in the associations between IL-6, IL-16 and VEGF and physiologic variables that predict outcomes. CONCLUSIONS: In stable COPD patients with similar airflow obstruction, there are gender differences in plasma biomarker levels and in the association between biomarker levels and important clinical or physiological variables. Further studies should confirm our findings

Plasma metabolomics and clinical predictors of survival differences in COPD patients

Background: Plasma metabolomics profile (PMP) in COPD has been associated with clinical characteristics, but PMP’s relationship to survival has not been reported. We determined PMP differences between patients with COPD who died an average of 2 years after enrollment (Non-survivors, NS) compared to those who survived (S) and also with age matched controls (C). Methods: We studied prospectively 90 patients with severe COPD and 30 controls. NS were divided in discovery and validation cohorts (30 patients each) and the results compared to the PMP of 30 S and C. All participants completed lung function tests, dyspnea scores, quality of life, exercise capacity, BODE index, and plasma metabolomics by liquid and gas chromatography / mass spectometry (LC/MS, LC/MS2 , GC/MS). Statistically, we used Random Forest Analysis (RFA) and Support Vector Machine (SVM) to determine metabolites that differentiated the 3 groups and compared the ability of metabolites vs. clinical characteristics to classify patients into survivors and non-survivors. Results: There were 79 metabolites statistically different between S and NS [p < 0.05 and false discovery rate (q value) < 0.1]. RFA and SVM classification of COPD survivors and non-survivors had a predicted accuracy of 74 and 85% respectively. Elevation of tricyclic acid cycle intermediates branched amino acids depletion and increase in lactate, fructose and xylonate showed the most relevant differences between S vs. NS suggesting alteration in mitochondrial oxidative energy generation. PMP had similar predictive power for risk of death as information provided by clinical characteristics. Conclusions: A plasma metabolomic profile characterized by an oxidative energy production difference between survivors and non-survivors was observed in COPD patients 2 years before death

TNFA-863 polymorphism is associated with a reduced risk of chronic obstructive pulmonary disease: a replication study

We replicated the previously reported association between the TNFA -863 SNP and COPD. TNFA -863A allele may confer a protective effect to the susceptibility to the disease in the Spanish populatio

Genomic characterization of individuals presenting extreme phenotypes of high and low risk to develop tobacco-induced lung cancer

Single nucleotide polymorphisms (SNPs) may modulate individual susceptibility to carcinogens. We designed a genome-wide association study to characterize individuals presenting extreme phenotypes of high and low risk to develop tobacco-induced non-small cell lung cancer (NSCLC), and we validated our results. We hypothesized that this strategy would enrich the frequencies of the alleles that contribute to the observed traits. We genotyped 2.37 million SNPs in 95 extreme phenotype individuals, that is: heavy smokers that either developed NSCLC at an early age (extreme cases); or did not present NSCLC at an advanced age (extreme controls), selected from a discovery set (n=3631). We validated significant SNPs in 133 additional subjects with extreme phenotypes selected from databases including >39,000 individuals. Two SNPs were validated: rs12660420 (p(combined)=5.66x10(-5); ORcombined=2.80), mapping to a noncoding transcript exon of PDE10A; and rs6835978 (p(combined)=1.02x10(-4); ORcombined=2.57), an intronic variant in ATP10D. We assessed the relevance of both proteins in early-stage NSCLC. PDE10A and ATP10D mRNA expressions correlated with survival in 821 stage I-II NSCLC patients (p=0.01 and p<0.0001). PDE10A protein expression correlated with survival in 149 patients with stage I-II NSCLC (p=0.002). In conclusion, we validated two variants associated with extreme phenotypes of high and low risk of developing tobacco-induced NSCLC. Our findings may allow to identify individuals presenting high and low risk to develop tobacco-induced NSCLC and to characterize molecular mechanisms of carcinogenesis and resistance to develop NSCLC

TNFA-863 polymorphism is associated with a reduced risk of Chronic Obstructive Pulmonary Disease: A replication study

<p/> <p>Background</p> <p>TNF-α mediated inflammation is thought to play a key role in the respiratory and systemic features of Chronic Obstructive Pulmonary Disease. The aim of the present study was to replicate and extend recent findings in Taiwanese and Caucasian populations of associations between COPD susceptibility and variants of the <it>TNFA </it>gene in a Spanish cohort.</p> <p>Methods</p> <p>The 3 reported SNPs were complemented with nine tag single nucleotide polymorphisms (SNP) of the <it>TNFA </it>and <it>LTA </it>genes and genotyped in 724 individuals (202 COPD patients, 90 smokers without COPD and 432 healthy controls). Pulmonary function parameters and serum inflammatory markers were also measured in COPD patients.</p> <p>Results</p> <p>The <it>TNFA </it>rs1800630 (-863C/A) SNP was associated with a lower COPD susceptibility (ORadj = 0.50, 95% CI = 0.33-0.77, p = 0.001). The -863A allele was also associated with less severe forms of the disease (GOLD stages I and II) (ORadj = 0.303, 95%CI = 0.14-0.65, p = 0.014) and with lower scores of the BODE index (< 2) (ORadj = 0.40, 95%CI = 0.17-0.94, p = 0.037). Moreover, the -863A carrier genotype was associated with a better FEV₁percent predicted (p = 0.004) and a lower BODE index (p = 0.003) over a 2 yrs follow-up period. None of the <it>TNFA </it>or <it>LTA </it>gene variants correlated with the serum inflammatory markers in COPD patients (p > 0.05).</p> <p>Conclusions</p> <p>We replicated the previously reported association between the <it>TNFA </it>-863 SNP and COPD. <it>TNFA </it>-863A allele may confer a protective effect to the susceptibility to the disease in the Spanish population.</p

Plasma protein levels in smokers without COPD and COPD.

<p>Levels values are shown as median in pg/dL with their 25–75^th percentiles.</p><p>ns = non significant.</p

Clinical characteristics of patients with COPD.

<p>BMI, body mass index. FEV₁%, forced expiratory volume in one second (% predicted).</p><p>FVC%, forced vital capacity (% predicted). MMRC, modified medical research council dyspnea scale. 6MWD, six-minute walk distance. TLC, total lung capacity.</p><p>IC, inspiratory capacity. BODE, body mass index, obstruction, dyspnea and exercise capacity index.</p><p>ns = non significant.</p><p>*mean±SD.</p><p>**median; 25–75^th percentiles.</p

Clinical characteristics of smokers without COPD of both genders.

<p>BMI, body mass index. FEV₁%, forced expiratory volume in one second (% predicted).</p><p>FVC%, forced vital capacity (% predicted).</p><p>ns = non significant.</p><p>*mean±SD.</p><p>**median; 25–75^th percentiles.</p

TNFA-863 polymorphism is associated with a reduced risk of chronic obstructive pulmonary disease: a replication study

We replicated the previously reported association between the TNFA -863 SNP and COPD. TNFA -863A allele may confer a protective effect to the susceptibility to the disease in the Spanish populatio