As for KEGG pathway enrichment analysis, there were 41 signaling pathways enriched (Figure 2D), including the common AD-related pathways such as PI3K-Akt signaling pathway, MAPK signaling pathway, ErbB signaling pathway, NF-κB signaling pathway, apoptosis, TNF signaling pathway, and estrogen signaling pathway. Here, TNF is linked to Alzheimer disease.