title: [Study of RASSF1A expression and promoter demethylation in Hep-2 cell line].
abstract: OBJECTIVE
  To investigate the effect of 5-Aza-dC and TSA to tumor suppressor gene RASSF1A expression and methylation level in Hep-2 cell line.
  
  
  METHODS
  Hep-2 cell line were cultured in vitro and handled with 5-Aza-dC and TSA. Detected RASSF1A expression and methylation level were detected before and after drug intervention using Realtime PCR and MSP.
  
  
  RESULTS
  (1) Before intervention with drug, tumor suppressor gene RASSF1A was weakly expressed and methylated in Hep-2 cell line. (2) With the effect of 5-Aza-dC and TSA, the methylation of RASSF1A gene was reversed. And the effect of combination of 5-Aza-dC and TSA was similar with 5-Aza-dC alone. There was no obvious effect using TSA alone. (3) With the effect of 5-Aza-dC and TSA, the expression of RASSF1A was improved. And the effect of 5-Aza-dC was stronger than TSA. Synergetic effect was found when using 5-Aza-dC and TSA simultaneously.
  
  
  CONCLUSIONS
  In Hep-2 cell line, Promoter methylation of tumor suppressor RASSF1A may play a very important role in loss of gene expression, but it is not the only cause. 5-Aza-dC and TSA can improve RASSF1A expression by reversing DNA methylation and histone deacetylation.
authors.affiliation: Department of Otolaryngology, Affiliated Shengjing Hospital of China Medical University, Shenyang, 110004, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.forename: Wenyue
authors.initials: W
authors.lastname: Ji
authors.forename: Yarong
authors.initials: Y
authors.lastname: Qu
authors.forename: Lixia
authors.initials: L
authors.lastname: He
authors.forename: Xudong
authors.initials: X
authors.lastname: Zhao
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D001374:Azacitidine / Q000031:analogs & derivatives / Q000494:pharmacology; D045744:Cell Line, Tumor; D019175:DNA Methylation; D015870:Gene Expression; D020868:Gene Silencing; D016147:Genes, Tumor Suppressor; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D025521:Tumor Suppressor Proteins / Q000235:genetics*
chemical_list: D000964:Antimetabolites, Antineoplastic; D006877:Hydroxamic Acids; C411762:RASSF1 protein, human; D025521:Tumor Suppressor Proteins; C012589:trichostatin A; D001374:Azacitidine