MAPK1 and pulmonary arterial hypertension: Interestingly, we found that the expression of RPS27A, MAPK1, STAT1, RPS6, FBL, RPS3, RPS2, and GART hub genes are positively correlated with hypoxia (ssGSEA score of hallmark hypoxia gene set) in the PAH (Spearman’s correlation test, p < 0.05) (Figure 7A).