BMPR2 and idiopathic pulmonary arterial hypertension: Therefore, we proposed the following mechanism: circGSAP acts as a sponge to suppress the functions of miR-27a-3p and increase BMPR2 levels, leading to the inhibition of PMECs proliferation and migration, increase of mortality, thus alleviating pulmonary arterial intimal injury in IPAH (Fig. 8).