title: Study on RIZ1 gene promoter methylation status in human esophageal squamous cell carcinoma.
abstract: OBJECTIVE
  To investigate the promoter region methylation status of retinoblastoma protein-interacting zinc finger gene 1 (RIZ1) in the human esophageal squamous cell carcinoma (ESCC) cell lines and tissues and verify the relationship between methylation of RIZ1 and oncogenesis, tumor progression and metastasis etc of ESCC.
  
  
  METHODS
  Methylation-specific polymerase chain reaction (MSP) was used to investigate the promoter region methylation status of RIZ1 in 6 ESCC cell lines. One cell line where RIZ1 promoter region methylation was detected was selected for the next study, where the cell line was treated with 5-aza-CdR. Real-time polymerase chain reaction was used to investigate its influence on the transcription of RIZ1. Experiments using frozen pathological specimens from 47 ESCC patients were performed using the same MSP methodology.
  
  
  RESULTS
  Promoter methylation of RIZ1 gene was detected in TE13, CaEs17 and EC109 cell lines and the cell line TE13 was chosen for further study. The expression of RIZ1 mRNA in TE-13 was up-regulated after treatment with 5-aza-CdR. The rate of methylation in carcinomas tissues was significantly higher than those in matched neighboring normal and distal ending normal tissue, and the deviation of data was statistically significant (χ(2) = 24.136, P < 0.01). Analysis of the gender, age familial history, tumour deviation, tumour saturation, lymph gland displacement and clinical staging of 47 samples from ESCC patients showed that the fluctuation of data was not statistically significant.
  
  
  CONCLUSIONS
  Promoter methylation may play an important role in the epigenetic silencing of RIZ1 gene expression in human ESCC. RIZ1 is considered to be a potential tumor suppressor gene and may be a biological parameter for testing early stage human ESCC.
authors.affiliation: Department of Cardiothoracic Surgery, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Shang-Wen
authors.initials: SW
authors.lastname: Dong
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.forename: Yi-Mei
authors.initials: YM
authors.lastname: Liu
authors.forename: Yuan-Tao
authors.initials: YT
authors.lastname: Cui
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
authors.forename: Shao-Jie
authors.initials: SJ
authors.lastname: Liang
authors.forename: Zhun
authors.initials: Z
authors.lastname: He
authors.forename: Pei
authors.initials: P
authors.lastname: Sun
authors.forename: Yuan-Guo
authors.initials: YG
authors.lastname: Wang
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D001374:Azacitidine / Q000494:pharmacology; D001483:Base Sequence; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor / Q000187:drug effects; D019175:DNA Methylation; D004268:DNA-Binding Proteins / Q000235:genetics*; D044127:Epigenesis, Genetic; D004938:Esophageal Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D020868:Gene Silencing; D011495:Histone-Lysine N-Methyltransferase / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D017422:Sequence Analysis, DNA; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D000964:Antimetabolites, Antineoplastic; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors; D011495:Histone-Lysine N-Methyltransferase; C093563:PRDM2 protein, human; D001374:Azacitidine