PECAM1 and Alzheimer disease: We intersected the genes in the turquoise module of WGCNA, which was closely related to the AD group, with the differentially expressed PRGs to obtain seven candidate hub genes for further analysis: BHLHE40, caspase 4 (CASP4), platelet and endothelial cell adhesion molecule 1 (PECAM1), pyruvate kinase M1/2 (PKM), serpin family B member 1 (SERPINB1), Toll-like receptor 2 (TLR2), and vascular endothelial growth factor A (VEGFA) (Figure 9A).