STAT3 and pulmonary arterial hypertension: Both miRNA-204′s and miRNA-let-7a’s anti-proliferative properties have been related to their suppressing of the IL-6/STAT3 signaling pathway, a central determinant of the hyperproliferative vascular cell phenotype in patients with idiopathic PAH (Lee et al., 2012; Chen et al., 2017).