KLF2 and cerebral cavernous malformation: Klf2 can trigger an endothelial-to-mesenchymal transition (endMT) (Dejana and Lampugnani, 2018), which is thought to contribute to the formation of CCM lesions because endothelial cells acquire mesenchymal properties (Maddaluno et al, 2013; Bravi et al, 2016; Dejana and Lampugnani, 2018).