title: Analysis of promoter non-CG methylation in prostate cancer.
abstract: BACKGROUND
  In vertebrates, DNA methylation occurs primarily at CG dinucleotides but recently, non-CG methylation has been found at appreciable levels in embryonic stem cells.
  
  
  METHODS
  To assess non-CG methylation in cancer, we compared the extent of non-CG methylation at several biologically important CG islands in prostate cancer and normal cell lines. An assessment of the promoter CG islands EVX1 and FILIP1L demonstrates a fourfold higher rate of non-CG methylation at EVX1 compared with FILIP1L across all cell lines. These loci are densely methylated at CG sites in cancer.
  
  
  RESULTS
  No significant difference in non-CG methylation was demonstrated between cancer and normal. Treatment of cancer cell lines with 5-azacytidine significantly reduced methylation within EVX1 at CG and CC sites, preferentially.
  
  
  CONCLUSIONS
  Non-CG methylation does not correlate with CG methylation at hypermethylated promoter regions in cancer. Furthermore, global inhibition of DNA methyltransferases does not affect all methylated cytosines uniformly.
authors: Department of Urology, University of Wisconsin School of Medicine & Public Health, Madison, WI, USA.
authors: Matthew
authors: M
authors: Truong
authors: Bing
authors: B
authors: Yang
authors: Jennifer
authors: J
authors: Wagner
authors: Joshua
authors: J
authors: Desotelle
authors: David F
authors: DF
authors: Jarrard
mesh_terms: D001374:Azacitidine / Q000494:pharmacology; D002352:Carrier Proteins / Q000235:genetics; D018899:CpG Islands / Q000235:genetics*; D003598:Cytoskeletal Proteins / Q000235:genetics; D019175:DNA Methylation / Q000235:genetics*; D018398:Homeodomain Proteins / Q000235:genetics; D006801:Humans; D008297:Male; D008780:Methyltransferases / Q000235:genetics; D011401:Promoter Regions, Genetic; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; C464562:FILIP1 protein, human; D018398:Homeodomain Proteins; C074437:EVX1 protein, human; D008780:Methyltransferases; D001374:Azacitidine