title: Status and significance of CpG island methylator phenotype in endometrial cancer.
abstract: BACKGROUND
  Endometrial cancer is a common gynecologic malignant disease, but patients with advanced disease have a poor prognosis. The CpG island methylator phenotype (CIMP) involves hypermethylation targeted toward the promoters of multiple genes.
  
  
  OBJECTIVE
  To investigate the role of epigenetic aberration of tumor-related genes in endometrial cancer.
  
  
  METHODS
  The promoter methylation status of 5 genes was examined in 35 endometrial cancer tissues, 15 matched adjacent normal endometrial tissues (NET) from the same cancer patients, and 22 benign endometria from unaffected patients by methylation-specific PCR. CIMP positivity (CIMP+) was defined as concordant methylation of ≥3 genes.
  
  
  RESULTS
  The methylation frequency of promoters for the 5 genes in the cancer tissues ranged from 37% for P16 to 57% for P14. Cancer and benign endometria, but not cancer and adjacent NET, significantly differed in methylation of P14, P16, ER, COX-2 and RASSF1A (p < 0.05). CIMP+ was frequent in cancer and adjacent NET (46 and 47%, respectively; p > 0.05), but absent in benign endometria. Moreover, CIMP+ was significantly correlated with methylation of P16 and COX-2 (r = 0.673 and 0.662, respectively; p < 0.001).
  
  
  CONCLUSIONS
  CIMP+ is an important and frequent epigenetic event in endometrial cancer or adjacent NET, and may be a biomarker for predicting early carcinogenesis. COX-2 is a good representative gene of CIMP+ in this cancer.
authors.affiliation: Department of Preventive Medicine, Shantou University Medical College, Shantou, PR China. qyzhang@stu.edu.cn
authors.forename: Qing-Ying
authors.initials: QY
authors.lastname: Zhang
authors.forename: De-Qing
authors.initials: DQ
authors.lastname: Yi
authors.forename: Li
authors.initials: L
authors.lastname: Zhou
authors.forename: Dong-Hong
authors.initials: DH
authors.lastname: Zhang
authors.forename: Tai-Mei
authors.initials: TM
authors.lastname: Zhou
mesh_terms: D000328:Adult; D000368:Aged; D018899:CpG Islands / Q000235:genetics*; D019175:DNA Methylation / Q000235:genetics*; D017931:DNA Primers / Q000737:chemistry; D016889:Endometrial Neoplasms / Q000235:genetics*; D005260:Female; D006801:Humans; D008875:Middle Aged; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics*
chemical_list: D017931:DNA Primers