Recently, we have demonstrated that PAK4 is overexpressed in PC, and it promotes the proliferation and survival of PC cells through AKT (RAC-alpha serine/threonine-protein kinase)- and ERK (extracellular signal-regulated kinase)-dependent activation of the nuclear factor-kappa B (NF-κB) pathway [14]. Here, PAK4 is linked to pachyonychia congenita.