To screen abnormally-expressed circular non-coding RNA (circRNA) in the blood of chronic obstructive pulmonary disease (COPD) patients based on high-throughput genome sequencing, and to explore the effects of significantly differentially expressed hsa_circRNA_0001478 on human pulmonary artery smooth muscle cells proliferation and apoptosis.

This was an experimental study.Using non-random sampling method, the blood samples were collected of COPD patients with pulmonary arterial hypertension and patients with simple COPD hospitalized in the Respiratory Department of the People′s Hospital of Ningxia Hui Autonomous Region from January to December 2021 and the healthy people for check-up during the same period.RNA sequencing (RNA-seq) was used for sequencing analysis, and the real-time fluorescent quantitative polymerase chain reaction (RT-PCR) was used to verify more than 10 times differentially expressed genes in the peripheral blood samples.The expression level of hsa_circRNA_0001478 after knockdown in human pulmonary artery smooth muscle cells (hPASMCs) was verified by RT-PCR; cell counting kit experiment was used to detect cell proliferation; Hoechst 33342 experiment was used to detect cell state and cell apoptosis through nuclear staining; Transwell assay was used to detect cell invasion and migration.

Based on the sequencing results, four circRNAs that were obviously highly expressed in the peripheral blood of COPD patients with pulmonary arterial hypertension were selected: hsa_circRNA_0001478, hsa_circRNA_0006872, hsa_circRNA_0001859, and hsa_circRNA_0016070, and the corresponding primers were constructed and verified by RT-PCR in COPD patients.It was found that only hsa_circRNA_0001478 showed obvious expression difference.The constructed si-circ plasmid significantly reduced the expression of hsa_circRNA_0001478 in hPASMCs, and cells transfected with si-circ showed reduced proliferation, migration, and invasion ability and increased cell apoptosis.

The abnormal expression of hsa_circRNA_0001478 affects the proliferation and apoptosis of hPASMCs, indicating that hsa_circRNA_0001478 may play an important role in the occurrence and development of COPD.

Pulmonary disease, chronic obstructive; RNA, circular; Pulmonary arterial hypertension; Cell proliferation; Apoptosis; Hsa_circRNA_0001478; Human pulmonary artery smooth muscle cells