FGFR1 and atherosclerosis: The two best characterized are the activation of the MEK5/ERK5/BMP pathway after the loss of Ccm1 or Ccm2 gene expression109, 110 and the activation of TGFβR signalling due to the loss of FGFR1 signalling input and decline in let-7 expression56, 80, 81 (Fig. 4) The former pathway is an important driver for EndMT in CCM settings while the latter is active in graft stenosis and atherosclerosis.