The knockdown of AEG-1/MTDH induces PC cell apoptosis through upregulation of FOXO3a activity, and also attenuates the constitutive activity of NF-κB and activator protein 1 (AP-1), with a corresponding depletion in the expression of NF-κB and AP-1-regulated genes. Here, MTDH is linked to pachyonychia congenita.