Silencing lncRNA CDKN2B-AS1 Alleviates Childhood Asthma Progression Through Inhibiting ZFP36 Promoter Methylation and Promoting NR4A1 Expression.

Abstract

LncRNA cyclin-dependent kinase inhibitor 2B antisense RNA 1 (CDKN2B-AS1) was found to be upregulated in plasma of patients with bronchial asthma. This study aimed to explore the roles and mechanisms of CDKN2B-AS1 in childhood asthma. We found that CDKN2B-AS1 was upregulated and zinc finger protein 36 (ZFP36) mRNA was downregulated in blood samples of children with asthma compared with healthy controls as measured by RT-qPCR. Human bronchial epithelial cell line BEAS-2B was treated with LPS to induce inflammation model. Small interfering RNA against CDKN2B-AS1 (si-CDKN2B-AS1) was transfected into LPS-treated BEAS-2B cells, and we observed that CDKN2B-AS1 silencing increased cell viability and inhibited apoptosis and inflammation cytokine levels in LPS-treated BEAS-2B cells. Methylation-specific PCR, ChIP, and RIP assays indicated that CDKN2B-AS1 inhibited ZFP36 expression by recruiting DNMT1 to promote ZFP36 promoter methylation. Co-immunoprecipitation (Co-IP) assay verified the interaction between ZFP36 and nuclear receptor subfamily 4 group A member 1 (NR4A1) proteins. Then rescue experiments revealed that ZFP36 knockdown reversed the effects of CDKN2B-AS1 silencing on BEAS-2B cell functions. ZFP36 overexpression facilitated apoptosis, inflammation, and p-p65 expression in BEAS-2B cells, while NR4A1 knockdown reversed these effects. Additionally, CDKN2B-AS1 silencing alleviated airway hyperresponsiveness and inflammation in ovalbumin (OVA)-induced asthma mice. In conclusion, silencing lncRNA CDKN2B-AS1 enhances BEAS-2B cell viability, reduces apoptosis and inflammation in vitro, and alleviated asthma symptoms in OVA-induced asthma mice in vivo through inhibiting ZFP36 promoter methylation and NR4A1-mediated NF-κB signaling pathway.