The missense mutation p.H288Y of Krüppel-like Factor 2 (KLF2) in pre-clinical PAH, idiopathic PAH, and heritable PAH were indicated to reduce the expressions of MicroRNA-181a-5p (miR-181a-5p) and MicroRNA-324-5p (miR-324-5p), the exosomal miRNAs induced by KLF2. Here, KLF2 is linked to pulmonary arterial hypertension.