The PPI network diagram of the intersected targets of four diseases, obesity, T2DM, AS, and NAFLD, associated with estrogen. In the (A–D) diagram, all targets are arranged from large to small according to the degree value, and each node represents a target. The larger the degree value, the larger the node size, the darker the color, and the inner circle is the core target. NR1I3 is a free node in the PPI network of the intersection target of estrogen and obesity. PRKCQ was a free node in the PPI network of the intersection target of estrogen and T2DM. NR1I3, CFTR, and HSD11B1 are free nodes in the PPI network of estrogen and NAFLD intersection targets. The free nodes were not displayed after the PPI network was processed by Cytoscape 3.9.1. (A) The intersected targets of estrogen and obesity. The core targets are SRC, ESR1, PTGS2, NR3C1, and CYP19A1. (B) The intersected targets of estrogen and T2DM. The core targets are SRC, ESR1, PTGS2, MMP-9, NR3C1, and CYP19A1. (C) The intersected targets of estrogen and AS. The core targets are PTGS2, SRC, ESR1, and CYP19A1. (D) The intersected targets of estrogen and NAFLD. The core targets are ESR1, PTGS2, CNR1. (E)The common targets in the Venn diagram were obtained for the four diseases and estrogen, respectively. (F) The PPI network diagram of the common targets in the intersected targets was obtained for the four diseases and estrogen, respectively. The outermost layer of each combination graph is the target; the blue node shows the number of diseases with a common target, the purple node shows the disease, and the line between the disease and the target represents the relationship. Abbreviations: AS, atherosclerosis; CFTR, CF transmembrane conductance regulator; CNR1, cannabinoid receptor 1; CYP19A1, cytochrome P450 family 19 subfamily A member 1; ESR1, estrogen receptor 1; HSD11B1, hydroxysteroid 11-beta dehydrogenase 1; MMP-9, matrix metalloproteinases-9; NAFLD, nonalcoholic fatty liver disease; NR1I3, nuclear receptor subfamily 1 group I member 3; NR3C1, nuclear receptor subfamily 3 group C member 1; PPI, protein-protein interaction; PRKCQ, protein kinase C theta; PTGS2, prostaglandin-endoperoxide synthase 2; SRC, SRC proto-oncogene, non-receptor tyrosine kinase; T2DM, type 2 diabetes mellitus.