NKRF and chronic obstructive pulmonary disease: RT-qPCR data showed that hsa-miR19-3p were significantly increased in LC tissues of patients with COPD than that of LC patients without COPD (p < 0.01 vs. LC patients without COPD), and there was no significant change in the mRNA level of NKRF between the two groups (p>0.05, Fig. 1C).