SNAIL/SLUG was observed in the nuclei of vWF-positive PAECs (Figure 1D) as well as in some ACTA2-positive cells in the neointima of occlusive lesions from patients with IPAH (Figure 1E) but it was not detected in PAs from unused donor control subjects (Supplemental Figure 1C). This evidence concerns the gene SNAI1 and idiopathic pulmonary arterial hypertension.