Development of microRNA expression signature for emphysema in COPD patients

To define the role of microRNAs and their mRNA targets in emphysema severity in COPD patients. We performed Agilent human miRNA oligo arrays (8x15K array, Part No. G4470A, Agilent Technologies) based on miRBase V9.1 on lung tissues from 9 mild and 20 moderate emphysema lungs obtained from patients undergoing curative resection for lung cancer. We identified 5 miRNAs and two of those were tested and validated technically using qRT-PCR. The predicted mRNA targets for the five miRNAs were identified in MSigDB using GSEA and their expression were negatively correlated in exvivo lung mRNA expression profile obtained from GEO datasets (GSE17770 and GSE1650). Increasing the expression of one of the miRNA target, miR-34c in BEAS-2B and HFL 1 cell lines resulted in the downregulation of 50 TargetScan and Pictar predicted targets of miR-34c.