title: MicroRNA-21 inhibits platelet-derived growth factor-induced human aortic vascular smooth muscle cell proliferation and migration through targeting activator protein-1.
abstract: OBJECTIVE
  This study is to investigate whether microRNA (miR)-21 inhibits platelet-derived growth factor-induced human aortic vascular smooth muscle cell (VSMC) proliferation and migration through targeting activator protein-1 (AP-1).
  
  
  METHODS
  VSMCs were transfected with the miR-21 or miR-21 inhibitor. Cell proliferation was determined using methyl thiazolyl tetrazolium assay. Cell migration was detected by transwell assay. Luciferase reporter assay was used to study the interaction between miR-21 and AP-1. The levels of mRNA were determined using quantitative real-time polymerase chain reaction, while protein expression was measured using Western blotting assay.
  
  
  RESULTS
  Low expression of miR-21 significantly inhibited VSMC proliferation, invasion and migration. The mRNA levels and protein expression of α-SMA and AP-1 were down-regulated by low expression of miR-21. In addition, luciferase reporter assay demonstrated that AP-1 might be a direct target gene of miR-21 in VSMC initiation and development. Moreover, up-regulation of AP-1 was critical for miR-21-mediated inhibitory effects on platelet-derived growth factor-induced cell proliferation and migration in human VSMCs.
  
  
  CONCLUSIONS
  In summary, miR-21 is a key molecule in regulating human VSMC proliferation and migration by targeting AP-1, suggesting that specific modulation of miR-21 in human VSMCs may become an attractive approach for the treatment of proliferative vascular diseases.
authors.affiliation: College of Pharmacy, Guangxi Medical University Nanning City, Guangxi Province, PR China.
authors.forename: Yumei
authors.initials: Y
authors.lastname: Li
authors.affiliation: Center of Biochemistry Research, University of South China Hengyang City, Hunan Province, PR China.
authors.forename: Limei
authors.initials: L
authors.lastname: Yan
authors.affiliation: College of Pharmacy, Guangxi Medical University Nanning City, Guangxi Province, PR China.
authors.forename: Wenyu
authors.initials: W
authors.lastname: Zhang
authors.affiliation: College of Pharmacy, Guangxi Medical University Nanning City, Guangxi Province, PR China.
authors.forename: Nan
authors.initials: N
authors.lastname: Hu
authors.affiliation: College of Pharmacy, Guangxi Medical University Nanning City, Guangxi Province, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: College of Pharmacy, Guangxi Medical University Nanning City, Guangxi Province, PR China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: The First Affiliated Hospital of Guangxi Medical University Nanning City, Guangxi Province, PR China.
authors.forename: Min
authors.initials: M
authors.lastname: Kang
authors.affiliation: College of Pharmacy, Guangxi Medical University Nanning City, Guangxi Province, PR China.
authors.forename: Hesheng
authors.initials: H
authors.lastname: Ou
keywords: activator protein-1; microRNA-21; migration; platelet-derived growth factor; proliferation; vascular smooth muscle cells