title: Frequent epigenetic inactivation of Myocardin in human nasopharyngeal carcinoma.
abstract: BACKGROUND
  Epigenetic silencing of tumor suppressor genes plays an important role in nasopharyngeal carcinoma (NPC) tumorigenesis. In the present study, we explore a novel target gene of epigenetic silencing in NPC, Myocardin, which is inactivated by promoter hypermethylation.
  
  
  METHODS
  Transcriptional expression levels of Myocardin were evaluated by reverse transcription-polymerase chain reaction (RT-PCR). Methylation status was addressed by methylation-specific PCR and bisulfite genomic sequencing.
  
  
  RESULTS
  Myocardin mRNA expression was inactivated in 4 of 5 NPC cell lines. Myocardin was aberrantly methylated in 4 of 5 NPC cell lines (80%) and in 48 of 65 NPC primary tumors (73.8%, but not in any of the 12 normal nasopharyngeal tissues tested. Myocardin expression could be reactivated in NPC cells after treatment with the demethylating agent 5-aza-2'-deoxycytidine (5-aza-dC).
  
  
  CONCLUSIONS
  Epigenetic inactivation of Myocardin is a frequent and tumor-specific event in NPC. Our findings suggest that Myocardin is a candidate tumor suppressor gene in NPC.
authors.affiliation: Department of Radiation Oncology, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China.
authors.forename: Fu
authors.initials: F
authors.lastname: Chen
authors.forename: Yingxi
authors.initials: Y
authors.lastname: Mo
authors.forename: Hao
authors.initials: H
authors.lastname: Ding
authors.forename: Xue
authors.initials: X
authors.lastname: Xiao
authors.forename: Shu Yi
authors.initials: SY
authors.lastname: Wang
authors.forename: Guangwu
authors.initials: G
authors.lastname: Huang
authors.forename: Zhe
authors.initials: Z
authors.lastname: Zhang
authors.forename: Sheng Zi
authors.initials: SZ
authors.lastname: Wang
mesh_terms: D000368:Aged; D002277:Carcinoma; D045744:Cell Line, Tumor; D016009:Chi-Square Distribution; D019175:DNA Methylation / Q000235:genetics*; D015536:Down-Regulation; D044127:Epigenesis, Genetic; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012016:Reference Values; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018709:Statistics, Nonparametric; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D000099251:Myocardin
chemical_list: D009687:Nuclear Proteins; D015534:Trans-Activators; D000099251:Myocardin