Among them, the level of miR-138-5p was confirmed to be downregulated by 50% in HBMEC/PHT cells but upregulated in HBMEC/PHT cells transfected with si-KCNQ1OT1 (Figure 2B). The gene discussed is KCNQ1OT1; the disease is pulmonary hypertension, primary, 1.