KEGG pathway analysis showed that the intersected genes upregulated in pulmonary macrophages from COPD patients were enriched in infectious and inflammatory pathways (PI3K-Akt, mTOR, Toll-like receptor, etc.), and that those downregulated ones were enriched in endocytosis, phagocytosis, lysosome, and phagosome (Figure 2A). This evidence concerns the gene AKT1 and chronic obstructive pulmonary disease.