More importantly, HIF1α and HIF2α, particularly HIF2α in pulmonary artery endothelial cells, plays a major role in the development of PAH (Skuli et al., 2009; Kim et al., 2013; Ball et al., 2014; Dai et al., 2016; Kapitsinou et al., 2016). Here, EPAS1 is linked to pulmonary arterial hypertension.