title: Quantitative DNA methylation analysis of selected genes in endometrial carcinogenesis.
abstract: OBJECTIVE
  Most endometrial carcinomas appear to develop from precursors (e.g., endometrial hyperplasia) that progress for several years. Patients who are ultimately diagnosed with carcinoma often present clinically with complaints of abnormal vaginal bleeding years before diagnosis, which offers an opportunity for early diagnosis and curative treatment. The analysis of DNA methylation may be used as a method for detecting endometrial cancer (EC). To test the potential clinical application of this method, we used quantitative methylation analysis of five genes in a full spectrum of endometrial lesions.
  
  
  METHODS
  This hospital-based, prospective, case-controlled study was conducted on 68 patients, which included patients who had a normal endometrium (n = 18), hyperplasia of the endometrium (n = 24), and EC (n = 26). Methylation levels of the following genes were determined by using real-time methylation-specific polymerase chain reaction (PCR) amplification: zinc finger protein 177 (ZNF177), collagen type XIV α1 (COL14A1), dihydropyrimidinase-like 4 (DPYSL4), homeobox A9 (HOXA9), transmembrane protein with epidermal growth factor-like and two follistatin-like domains 2 (TMEFF2). The methylation index (MI) cutoff values for the different diagnoses were determined to test the sensitivity and specificity of the method and to generate the receiver operating characteristic (ROC) curves. The Mann-Whitney U test was used to test between-group differences in the MI.
  
  
  RESULTS
  The MI of the five genes was significantly higher in EC than the MIs in specimens of hyperplasia of endometrium and normal appearance (p < 0.001). The ROC analysis demonstrated that the sensitivity, specificity, and accuracy for detecting EC were 92.3%, 94.4%, and 95.1%, respectively, for ZNF177; 92.3%, 94.4%, and 95.7%, respectively, for COL14A1; 80.8%, 94.4%, and 81.4%, respectively, for HOXA9; 65.4%, 94.4%, and 89.5%, respectively, for TMEFF2; and 61.5%, 94.4%, and 63.3%, respectively, for DPYSL4. The combined testing of ZNF177 and COL14A1 had the best specificity (100%), but compromised sensitivity (88.5%).
  
  
  CONCLUSIONS
  Promoter methylation of ZNF177, COL14A1, HOXA9, DPYSL4, and TMEFF2 genes is a frequent epigenetic event in EC. Furthermore, the epigenetic hypermethylation of TMEFF2 may be a valuable marker for identifying undetected EC within endometrial hyperplasia.
authors.affiliation: Division of Pulmonary and Critical Care, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC; Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: Ying-Chieh
authors.initials: YC
authors.lastname: Chen
authors.affiliation: Bureau of Investigation, Ministry of Justice, New Taipei City, Taiwan, ROC.
authors.forename: Chun-Ming
authors.initials: CM
authors.lastname: Tsao
authors.affiliation: Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: Chih-Chi
authors.initials: CC
authors.lastname: Kuo
authors.affiliation: Department of Obstetrics and Gynecology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: Mu-Hsien
authors.initials: MH
authors.lastname: Yu
authors.affiliation: Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan, ROC; Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: Ya-Wen
authors.initials: YW
authors.lastname: Lin
authors.affiliation: Department of Obstetrics and Gynecology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: Chu-Ying
authors.initials: CY
authors.lastname: Yang
authors.affiliation: Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: Hsin-Jung
authors.initials: HJ
authors.lastname: Li
authors.affiliation: Cancer Center, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan, ROC.
authors.forename: Ming-De
authors.initials: MD
authors.lastname: Yan
authors.affiliation: Department of Obstetrics and Gynecology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: Tun-Jun
authors.initials: TJ
authors.lastname: Wang
authors.affiliation: School of Public Health, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: Yu-Ching
authors.initials: YC
authors.lastname: Chou
authors.affiliation: Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan, ROC; Department of Obstetrics and Gynecology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC. Electronic address: su108868@gmail.com.
authors.forename: Her-Young
authors.initials: HY
authors.lastname: Su
mesh_terms: D063646:Carcinogenesis / Q000235:genetics*; D016022:Case-Control Studies; D019175:DNA Methylation; D004273:DNA, Neoplasm / Q000032:analysis*; D055088:Early Detection of Cancer / Q000379:methods*; D016889:Endometrial Neoplasms / Q000175:diagnosis / Q000235:genetics*; D005260:Female; D052138:Genes, Neoplasm / Q000235:genetics*; D006801:Humans; D011401:Promoter Regions, Genetic; D011446:Prospective Studies; D012372:ROC Curve; D060888:Real-Time Polymerase Chain Reaction; D013624:Taiwan
chemical_list: D004273:DNA, Neoplasm
keywords: COL14A1; DNA methylation; TMEFF2; endometrial cancer; hyperplasia of the endometrium