WNK2 and extramammary Paget disease: In line with this, mitogen-activated protein kinase and phosphoinositide 3-kinase signatures, as key upstream signaling factors for cell cycling, were higher in EMPD than in breast cancer samples, regardless of IHC/FISH status, highlighting an aggressive feature of metastatic EMPD and suggesting that targeting these pathways may be a potential therapeutic target (Figure 2D).