The Regulatory Role of miR-107–Cdk6-Rb Pathway in Airway Smooth Muscle Cells in Asthma

Abstract

Yi Xiong,1,2,* Yani Luo,2,* Ting Yuwen,2,* Jiana Li,2 Rongchang Chen,3 Fei Shi1 1Emergency Department, Shenzhen People’s Hospital, Shenzhen, Guangdong Province, People’s Republic of China; 2Biomedical Research Institute, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong Province, People’s Republic of China; 3Key Laboratory of Shenzhen Respiratory Diseases, Institute of Shenzhen Respiratory Diseases, Shenzhen People’s Hospital, Shenzhen, Guangdong Province, People’s Republic of China*These authors contributed equally to this workCorrespondence: Rongchang Chen, Email [email protected] Fei Shi, Email [email protected]: Airway remodeling is a significant pathological change of asthma. This study aimed to detect differentially expressed microRNAs in the serum of asthma patients and airway smooth muscle cells (ASMCs) of asthmatic mice, exploring their role in the airway remodeling of asthma.Methods: The differentially expressed microRNAs in the serum of mild and moderate-severe asthma patients compared to healthy subjects were revealed using the “limma” package. Gene Ontology (GO) analysis was used to annotate the functions of microRNA target genes. The relative expressions of miR-107 (miR-107-3p in mice sharing the same sequence) in the primary airway smooth muscle cells (ASMCs) of the asthma mice model were tested by RT-qPCR. Cyclin-dependent kinases 6 (Cdk6), a target gene of miR-107, was predicted by algorithms and validated by dual-luciferase reporter assay and Western blot. The roles of miR-107, Cdk6, and protein Retinoblastoma (Rb) in ASMCs were examined by transwell assay and EDU KIT in vitro.Results: The expression of miR-107 was down-regulated in both mild and moderate-severe asthma patients. Intriguingly, the level of miR-107 was also decreased in ASMCs of the asthma mice model. Up-regulating miR-107 suppressed ASMCs’ proliferation by targeting Cdk6 and the phosphorylation level of Rb. Increasing the expression of Cdk6 or suppressing Rb activity abrogated the proliferation inhibition effect of ASMCs induced by miR-107. In addition, miR-107 also inhibits ASMC migration by targeting Cdk6.Conclusion: The expression of miR-107 is down-regulated in serums of asthma patients and ASMCs of asthmatic mice. It plays a critical role in regulating the proliferation and migration of ASMCs via targeting Cdk6.Keywords: asthma, microRNA microarray, airway smooth muscle cells, miR-107, Cdk6

Keywords

• asthma
• microrna microarray
• airway smooth muscle cells
• mir-107
• cdk6