PKM and pulmonary arterial hypertension: The reduced expression of miR-124 was observed in pulmonary vascular and circulating progenitor endothelial cells isolated from PAH patients, leading to the identification of miR-124 as a significant regulator of enhanced endothelial cell glycolysis in PAH via polypyrimidine tract-binding protein (PTBP1) and Pyruvate Kinase M2 (PKM2).