Previous study has demonstrated that the genes expression of glycolytic enzymes including glucose transporter 1 (GLUT1), hexokinase 2 (HK2) and lactate dehydrogenase A (LDHA) are significant higher in human pulmonary artery endothelial cells (HPAEC) than in chronic thromboembolic pulmonary hypertension endothelial cells (CTEPH-EC) and pulmonary arterial hypertension endothelial cells (PAH-EC) (24). Here, HK2 is linked to pulmonary arterial hypertension.