Sanja Popović-Grle

Decreased soluble dipeptidyl peptidase IV activity as a potential serum biomarker for COPD.

OBJECTIVES The objective of this study was to measure soluble dipeptidyl peptidase IV (sDPPIV) activity in sera of patients with stable chronic obstructive pulmonary disease (COPD) in comparison to healthy controls. The main goal was to assess changes in the enzyme activity in relation to severity of the disease, age and smoking history and to evaluate diagnostic accuracy for prediction of COPD by level of serum sDPPIV activity. DESIGN AND METHODS The study included 106 patients with stable COPD (GOLD II-GOLD IV stages) and 38 healthy controls. Serum sDPPIV activity as well as some inflammatory markers (CRP, total and differential leukocyte counts) was measured. Multivariate logistic regression models were applied to analyze association of sDPPIV activity and inflammatory markers in risk estimation for COPD development. RESULTS sDPPIV activity in COPD patients was significantly reduced when compared to healthy controls. Decrease was observed already in GOLD II stage. Age and smoking history did not influence sDPPIV activity. Very good diagnostic accuracy (AUC=0.833; sensitivity and specificity of 85.7% and 78.9%, respectively) for GOLD II and good diagnostic accuracy (AUC=0.801; sensitivity and specificity of 65.1% and 86.8%, respectively) for total cohort of COPD patients were found. The multivariate logistic regression model showed that the use of sDPPIV in combination with CRP and lymphocyte proportion improved diagnostic strength and gave an AUC of 0.933. CONCLUSIONS sDPPIV activity is decreased in COPD patients as early as in GOLD II stage. Very good diagnostic accuracy of sDPPIV activity suggests it as a candidate biomarker for early diagnosis of COPD.

Association of hsp70-2 (+1267A/G), hsp70-hom (+2437T/C), HMOX-1 (number of GT repeats) and TNF-alpha (+489G/A) polymorphisms with COPD in Croatian population.

OBJECTIVE To test for possible association of hsp70-2 (+1267A/G), hsp70-hom (+2437T/C), HMOX-1 (number of GT repeats) and TNF-α (+489G/A) polymorphisms with chronic obstructive pulmonary disease (COPD) in Croatian population. METHODS Genotyping of DNA isolated from whole blood of 130 COPD patients (as defined by spirometry) and 95 healthy controls was performed. Fragment size analysis upon restriction enzyme digestion and/or sequencing was used for genotype/allele definition. Significance of findings was tested using χ(2) test. RESULTS hsp70-2 (+1267A/G) polymorphism was significantly associated with COPD. Results of genotyping analysis indicated that a genotype carrying G allele was preferentially associated with COPD; odds ratio (OR)=1.50, 95% confidence interval (CI)=1.00-2.24 and P=0.061. OR for the GG genotype was 3.47 with CI=1.26-9.56 and P=0.04. No association for hsp70-hom (+2437T/C), TNF-α (+489G/A) and HMOX-1 (number of GT repeats) polymorphisms were found. In addition, comparison of genotype frequencies among different stages of disease severity (GOLD II-IV) revealed no discrimination for any of the tested polymorphisms. CONCLUSION This study is supporting the association of hsp70-2 (+1267A/G) polymorphism and COPD. Higher frequency of G allele and GG genotype in Croatian COPD patients was observed. There was no evidence for the association of hsp70-hom (+2437T/C), TNF-α (+489G/A) SNPs and HMOX-1 (number of GT repeats) polymorphism with COPD. Allele and genotype frequencies for all of the tested polymorphisms show no association with disease severity (GOLD II-IV).