Identification of Prognostic Value of Rs3735590 Polymorphism in 3'-Untranslated Region (3'-UTR) of Paraoxonase 1 (PON-1) in Chronic Obstructive Pulmonary Disease Patients who Received Coronary Artery Bypass Grafting (CABG).

BACKGROUND/AIMS: In the treatment of serious and symptomatic coronary heart disease (CHD), coronary artery bypass grafting (CABG) is a frequently utilized intervention. In addition, the risk of CHD is strongly associated with the low activity of paraoxonase-1 (PON1), whose 3'-UTR harbors an rs3735590 polymorphism. The aim of this study was to investigate whether the rs3735590 polymorphism could be used as a prognosis marker in chronic obstructive pulmonary disease (COPD) patients undergoing CABG. In addition, the hypothesis, i.e., the rs3735590 polymorphism may be involved in the regulation of PON1 gene expression via modulating its interaction with miRNAs, was tested in this study.

METHODS

292 patients diagnosed with COPD and treated with CABG were recruited for this study. Genomic DNA was extracted from clinical samples, and real-time quantitative PCR and Western-blot were used to measure the expression of miR-616 and PON1 in liver cells of different genotypes.

RESULTS

292 COPD patients were divided into three groups according to their genotypes, i.e., rs3735590: CC (212), TC (75), and TT (5), respectively (TC and TT were merged in one group of T carriers for statistical analyses). Patients with the CC genotype were associated with a shorter event-free survival time as compared to patients with the T genotypes. In addition, PON1 was confirmed as a direct target gene of miR-616, while experiments with primary cells of different genotypes showed that miR-616 inhibited the expression of PON1 in CC cells. On the contrary, rs3735590 impaired such inhibitory effect of miR-616 in TT cells.

CONCLUSION

The rs3735590 polymorphism of PON1 acts as a prognostic biomarker in COPD patients treated by CABG.