CXCL9 and pulmonary arterial hypertension: Kaplan-Meier analysis further showed that the overall survival of patients with PC was inversely associated with the gene expression levels of PLAU, CXCL10, CXCL9, MET, and IL1RN (P < 0.05; Figures 10A–E); however, the expression levels of PAH and PKD1 had positive associations with the prognosis of patients with PC (P < 0.05; Figures 10F,G).