ALOX5 and pulmonary arterial hypertension: 5-LO and LTB4 also induce early death of pulmonary arterial endothelial cells (ECs), cause the survival cells to become apoptosis-resistant and proliferative, change the properties of these ECs to acquire endogenous 5-LO expression, and transform them into proinflammatory phenotypes; responses are implicated in the PAH pathogenesis (Tian et al., 2013; Qian et al., 2015; Tian et al., 2019).