PIK3CA and vascular malformation: 2011). Interestingly, it also serves as a central hub of signal integration of numerous protein kinases including AMPK, CAMKII, as well as AKT. Recently, vascular malformations arising from mutations in PIK3CA have been shown to be sensitive to rapamycin treatment in mice as well as humans (Limaye et al. 2015; Castel et al. 2016; di Blasio et al. 2018).