KL and chronic kidney disease: In both the GSE104954 (CKD) and GSE108112 (CKD) datasets, the biological process most associated with Klotho gene is the inflammatory response (Fig. 2A, E), the cellular component most related to the Klotho gene is extracellular exosome (Fig. 2B, F), and the molecular function most associated with Klotho gene is protein binding (Fig. 2C, G).