WNK2 and glioblastoma: Treatment optimisation for the group of GBM patients is therefore warranted. Gene expression profiling showed that more than 90% of all glioblastomas have activating mutations in the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) and phosphoinositide 3-kinase/Akt (PI3K/Akt) cell signaling pathways [4].