The robust activation of ERK1/2 signaling in the present work is consistent with a series of recent studies in which blocking Smad-mediated canonical TGF-β signal transduction in different mouse aneurysm models invariably boosts the activation of the ERK1/2-mediated non-canonical TGF-β pathway20, 21, 29, 30. Here, TGFB1 is linked to aneurysm.