title: The p53/miR-34a/SIRT1 Positive Feedback Loop in Quercetin-Induced Apoptosis.
abstract: BACKGROUND
  The anti-tumor effects of quercetin have been reported, but the underlying molecular mechanisms remain to be elucidated. The aim of present study was to explore the role of miRNA in the anticancer effects of quercetin.
  
  
  METHODS
  The differential miRNAs expression between the HepG2 and Huh7 cells treated by quercetin were detected by microarray. The xCELLigence, Flow cytometry, RT-PCR and Western blot were used to analyze the cell proliferation, cell apoptosis, cell cycle arrest, anti-tumor genes, and protein expression.
  
  
  RESULTS
  miR-34a was up-regulated in HepG2 cells treated by quercetin exhibiting wild-type p53. When inhibiting the miR-34a, the sensitivity of the cells to quercetin decreased and the expression of the SIRT1 was up-regulated, but the acetylation of p53 and the expression of some genes related to p53 down-regulated.
  
  
  CONCLUSIONS
  miR-34a plays an important role in the anti-tumor effects of querctin in HCC, miR-34a may be a tiemolecule between the p53 and SIRT1 and is composed of a p53/miR-34a/SIRT1 signal feedback loop, which could enhance apoptosis signal and significantly promote cell apoptosis.
authors.affiliation: State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University. Collaborative Innovation Centre for Diagnosis and Treatment of Infectious Diseases, Hangzhou, China.
authors.forename: Guohua
authors.initials: G
authors.lastname: Lou
authors.forename: Yanning
authors.initials: Y
authors.lastname: Liu
authors.forename: Shanshan
authors.initials: S
authors.lastname: Wu
authors.forename: Jihua
authors.initials: J
authors.lastname: Xue
authors.forename: Fan
authors.initials: F
authors.lastname: Yang
authors.forename: Haijing
authors.initials: H
authors.lastname: Fu
authors.forename: Min
authors.initials: M
authors.lastname: Zheng
authors.forename: Zhi
authors.initials: Z
authors.lastname: Chen
mesh_terms: D017209:Apoptosis / Q000187:drug effects* / Q000235:genetics; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects / Q000235:genetics; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D056945:Hep G2 Cells; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D011794:Quercetin / Q000494:pharmacology*; D056564:Sirtuin 1 / Q000235:genetics*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics
chemical_list: C522425:MIRN34 microRNA, human; D035683:MicroRNAs; D016159:Tumor Suppressor Protein p53; D011794:Quercetin; C447939:SIRT1 protein, human; D056564:Sirtuin 1