title: The correlation between CpG methylation on promoter and protein expression of E-cadherin in oral squamous cell carcinoma.
abstract: BACKGROUND
  Reduction of E-cadherin in most common epithelial tumors relates to metastasis, which results from the silence of E-cadherin by CpG methylation.
  
  
  METHODS
  We examined the E-cadherin expression by immunohistochemical staining and detected methylation by methylation-specific polymerase chain reaction (MSP) in 48 primary oral SCC tissues.
  
  
  RESULTS
  The results showed that 41 out of 48 (85.4%) cancerous tissues and 16 out of 48 (33.3%) nearby non-cancerous tissues had CpG methylation on the promoter region of E-cadherin. In these non-cancerous tissues, 2 out of 16 (12.5%) had no methylation change in their paired cancerous part. Immunohistochemical study showed that a decreased expression pattern was found in the tissue which had CpG methylation on the promoter region, but an over expression island or aberrant expression was also frequently found in these cases.
  
  
  CONCLUSIONS
  The methylation of E-cadherin in oral SCC may occur in the precancerous stage and the process is dynamic, which has no relationship with the aberrant expression of E-cadherin protein.
authors.affiliation: Departments of Molecular Medicine and Laboratory Medicine, China Medical College Hospital, Taichung, Taiwan.
authors.forename: Kun-Tu
authors.initials: KT
authors.lastname: Yeh
authors.forename: Mu-Chin
authors.initials: MC
authors.lastname: Shih
authors.forename: Ting Hsu
authors.initials: TH
authors.lastname: Lin
authors.forename: Jui-Chang
authors.initials: JC
authors.lastname: Chen
authors.forename: Jan-Yi
authors.initials: JY
authors.lastname: Chang
authors.forename: Chi-Feng
authors.initials: CF
authors.lastname: Kao
authors.forename: Keh-Liang
authors.initials: KL
authors.lastname: Lin
authors.forename: Jan-Gowth
authors.initials: JG
authors.lastname: Chang
mesh_terms: D000328:Adult; D000368:Aged; D015820:Cadherins / Q000096:biosynthesis* / Q000235:genetics*; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000378:metabolism*; D018899:CpG Islands; D019175:DNA Methylation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000235:genetics* / Q000378:metabolism*; D011401:Promoter Regions, Genetic
chemical_list: D015820:Cadherins