ECs that have undergone partial EndMT were identified in the mouse heart (CD31/PECAM-1 and FSP-1) during the progression of cardiac fibrosis (Zeisberg et al., 2007b) as well as in the mouse brain (CD31/PECAM-1 and N-cadherin) in cerebral cavernous malformation (CCM) (Maddaluno et al., 2013). Here, PECAM1 is linked to cerebral cavernous malformation.