Abstract: Objective To explore the expression of miR-144 in the peripheral blood serum and monocytes from patients with chronic obstructive pulmonary disease (COPD) and its clinical significance. Methods Fifty-eight COPD patients at the stable period admitted to our hospital from March 2020 to June 2021 were selected as the observation group, and 45 healthy patients during the same period were selected as the control group. The general clinical data of all patients were collected. Real-time fluorescent quantitative PCR ( qRT-PCR) was used to detect the expression level of miR-144 in the peripheral blood serum and monocytes of all patients. The relationship between the expression level of miR-144 in the peripheral blood serum and monocytes and the lung function in patients with COPD was analyzed. Pearson correlation was used to analyze the correlation between the expression level of miR-144 in the peripheral blood serum and monocytes of COPD patients and the forced expiratory volume in first second (FEV1). ROC curve was used to analyze the diagnostic value of miR-144 expression levels in the peripheral blood serum and monocyte for COPD. Results The expression level of miR-144 in the peripheral blood serum and monocytes of COPD patients was significantly higher compared with the control group, (P < 0. 05). The expression level of miR-144 in the peripheral blood serum and monocytes of COPD patients increased with the aggravation of lung function, and the difference was statistically significant (P< 0. 05). The results of Pearson correlation analysis showed that the expression level of miR-144 in the peripheral blood serum and monocytes of COPD patients was negatively correlated with FEV1 ( r = - 0. 517, r = - 0. 463, P< 0. 05). ROC curve analysis results showed that the areas under the ROC curve (AUCs) of miR-144 levels in the peripheral blood serum and monocyte for the diagnosis of COPD were 0. 857 and 0. 849, with the cut-off values to be 1. 371 and 1. 890, the sensitivities to be 84. 50 % and 84. 50 % , and the specificities to be 80. 00 % and 88. 90 % , respectively. Conclusion The expression level of miR-144 in the peripheral blood serum and monocyte of patients with COPD is significantly up-regulated, they participate in the regulation of the development of the disease, and have a certain diagnostic value for the occurrence of COPD.

Key words: chronic obstructive pulmonary disease, miR-144, peripheral blood mononuclear cells