HIF1A and pulmonary arterial hypertension: Moreover, protein levels of key glycolytic enzymes PFKP and HKII were significantly higher in human PAH PAVSMC compared to controls (Figures 2E–G), and HIF1α over accumulation was detected in six out of seven PAVSMC from PAH patients compared to one out of five non-diseased (control) subjects (Supplementary Figure 2).