AKT1 and pachyonychia congenita: All the mechanisms affecting bone metastasis from PC can be separated into the following types: (1) PI3K/Akt signal transduction pathway is dominant [32–36]; (2) TGF-β signal transduction pathway was dominant [37–39]; (3) miR-RNA was dominant [34, 35, 40–42]; (4) other signal transduction pathways and drugs [36, 39, 43–64] (Fig. 2).