SIAH2 and pulmonary arterial hypertension: Furthermore, GLY, 4-PBA and VK3 administration attenuated the increases of RVSP, mPAP and RV/(LV+S), right ventricular hypertrophy, and pulmonary vascular remodeling by targeting on PERK/ATF4/SIAH2/HIPK2 pathway in PAH rats.