Hopper et al. reported enhanced expression of HMGA1 in pulmonary arterial endothelial cells of patients with idiopathic pulmonary arterial hypertension (PAH), and the upregulation of HMGA1 promoted endothelial-mesenchymal transition, accelerating the progression of PAH [12]. Here, HMGA1 is linked to idiopathic pulmonary arterial hypertension.