The genes corresponding to these targets were compared with 230 LUAD/COVID-19 DEGs, and 6 intersecting genes were obtained (Fig. 6A), including SLC6A4, MIF, DPP4, PRF1, SERPING1, and IL6. In addition, we visualized the interaction of these intersecting targets and performed a network topology analysis (Fig. 6B). This evidence concerns the gene DPP4 and COVID-19.