On the other hand, among male individuals, PC is the most common, non-dermatological epithelial malignant tumour in developed countries [101] and its aggressive nature has been investigated and correlated with important signalling pathways—mostly PI3K/Akt pathway-related—involved in proliferation, invasion, migration and cell survival [102,103,104,105]. Here, AKT1 is linked to pachyonychia congenita.