So we further investigated the correlation of miR-4456 and CCL3 expression in very severe COPD tissues (n = 76, Supplementary Figure S1 and Supplementary Table S1), which showed a significant negative correlation (r = −0.8813, p < 0.0001), indicating a potential suppressive role of miR-4456 in the progression of severe COPD. The gene discussed is CCL3; the disease is chronic obstructive pulmonary disease.