CCL2 and chronic obstructive pulmonary disease: Transcriptional network analysis and enrichment analysis for pathways and processes of these 236 common genes revealed that the most significantly enriched TF was CREB1 (Supplementary file 1: containing Supplementary Table 10) and the most significantly enriched pathways related to cell adhesion, CCL2 signaling, immune cell migration, myeloid differentiation, neutrophil activation, and inter-cellular interactions in COPD (Supplementary file 1: containing Supplementary Table 11).