Consistent with these observations, Good et al. determined the presence of EndMT by assessing the colocalization of von Willebrand factor and α-smooth muscle actin (α-SMA) in the pulmonary endothelium from the hypoxia/SU5416 preclinical murine pulmonary artery hypertension (PAH) model and systemic sclerosis-associated-PAH (SSc-PAH) patients. This evidence concerns the gene ACTA1 and pulmonary arterial hypertension.