P7‐31: The role of KIAA1462 in chronic obstructive pulmonary disease (COPD)

a history of exacerbation, and there are no good predictive biomarkers for exacerbation so far. Extracellular vesicles (EVs), in which contains a variety of functional molecules including microRNAs, work as intercellular messengers and are also involved in pathogenesis of various diseases. Because the contents of EVs are changed according to pathogenic conditions, many researchers try to utilize EVs as biomarkers. Aims: We investigated serum EV microRNAs in the frequent exacerbators of COPD to explore the pathogenesis of exacerbation as well as the possibilities of EV microRNAs as predictive biomarkers for a risk of exacerbation. Methods: We recruited the COPD patients who had 2 or more exacerbations in the past year as the frequent exacerbators. We also recruited the COPD patients who had no exacerbations as controls. Gender, age, and treatment of controls were matched with those of the exacerbators. Their serum samples were used for isolation of EVs. Total RNA in EVs was isolated for comprehensive expression analyses of microRNAs using microarrays. Results: 7 microRNAs including hsa-miR-524-3p were decreased in frequent exacerbators, whereas 31 microRNAs including hsa-miR-100-5p were increased. Conclusions: The expression profile of serum EV microRNAs in frequent exacerbators of COPD was different from that in the COPD patients without frequent exacerbations, which may suggest the involvement of microRNAs in the pathogenesis of COPD exacerbation.