Chronic obstructive pulmonary disease: MicroRNAs and exosomes as new diagnostic and therapeutic biomarkers.

Chronic obstructive pulmonary disease (COPD) is known as a progressive lung disease and the fourth leading cause of death worldwide. Despite valuable efforts, there is still no accurate diagnostic and prognostic tool for COPD. Hence, it seems that finding new biomarkers could contribute to provide better therapeutic platforms for COPD patients. Among various biomarkers, microRNAs (miRNAs) have emerged as new biomarkers for the prognosis and diagnosis of patients with COPD. It has been shown that deregulation of miRNAs targeting a variety of cellular and molecular pathways such as Notch, Wnt, hypoxia-inducible factor-1α, transforming growth factor, Kras, and Smad could be involved in COPD pathogenesis. Multiple lines of evidence have indicated that extracellular vesicles such as exosomes could carry a variety of cargos (i.e., mRNAs, miRNAs, and proteins) which transfer various cellular and molecular signals to recipient cells. Here, we summarized various miRNAs which could be applied as diagnostic and prognostic biomarkers in the treatment of patients with COPD. Moreover, we highlighted the role of extracellular vesicles containing miRNAs as diagnostic and prognostic biomarkers in COPD patients.