Clinical value of lncRNA SOX2-OT in pulmonary arterial hypertension and its role in pulmonary artery smooth muscle cell proliferation, migration, apoptosis, and inflammatory.

Background: Non-coding RNA is confirmed to be involved in pulmonary arterial hypertension (PAH).

Objectives: This study investigated the clinical value and potential mechanisms of the long noncoding RNA (lncRNA) SRY-box transcription factor 2 overlapping transcript (SOX2-OT) in PAH.

Methods: SOX2-OT levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR) in serum of 82 patients with PAH and 76 healthy controls. Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic value of SOX2-OT. Human pulmonary arterial smooth muscle cells (hPASMCs) were treated by hypoxia to construct PAH cell models. Proliferation, migration, apoptosis, and inflammatory cytokines levels of hPASMCs were examined by CCK-8, Transwell, flow cytometry, and ELISA assay. Dual-luciferase reporter gene assays were performed to verify the target relationships between miR-455-3p and SOX2-OT, as well as small ubiquitin-related modifier 1 (SUMO1).

Results: Serum SOX2-OT was highly expressed in patients with PAH (P < 0.05). And elevated SOX2-OT levels significantly differentiated PAH patients from healthy controls, confirming high diagnostic feasibility. What's more, SOX2-OT was increased in hypoxia-induced hPASMCs in a time-dependent manner. Silencing SOX2-OT could reverse hypoxia-induced proliferation, migration, anti-apoptosis, and inflammation of hPASMCs (P < 0.05). However, rescue experiments showed that this reversal effect of silencing SOX2-OT was attenuated by suppressed miR-455-3p, which was presumably achieved by SUMO1 (P < 0.05).

Conclusions: Elevated SOX2-OT is a feasible diagnostic marker for PAH, and its silencing may attenuated hypoxia-induced hPASMCs proliferation, migration, anti-apoptosis, and inflammation by modulating the miR-455-3p/SUMO1 axis, preventing vascular remodeling and PAH progression. Our research provided new insights for PAH treatment.