title: Hypermethylation of miR-203 in endometrial carcinomas.
abstract: OBJECTIVE
  Aberrant expression of SOX4 in endometrial cancer has been identified and partially was contributed to hypermethylation of miR-129-2. Other miRNAs are suspected to influence SOX 4 as well. The current study seeks to identify other hypermethylated miRNAs that regulate SOX4 in endometrial carcinomas.
  
  
  METHODS
  Methylation levels of miRNA promoter regions were measured by combined bisulfite restriction analysis (COBRA) and pyrosequencing assays. Gene expression was determined by RT-qPCR. Methylation level of a miRNA locus was corrected with clinicopathologic factors for 252 gynecological specimens.
  
  
  RESULTS
  In silico analysis identified 13 miRNA loci bound on the 3'-UTR of SOX4. Using COBRA assays, increased methylation of miR-203, miR-219-2, miR-596, and miR-618 was detected in endometrial cancer cells relative to those seen in a normal cell line and in normal endometrium. Transfection of a miR-203 mimic decreased SOX4 gene expression. Hypermethylation of miR-203 was detected in 52% of type I endometrioid endometrial carcinomas (n=131) but was not seen in any of 10 uninvolved normal endometria (P<0.001). Methylation status of miR-203 was significantly associated with microsatellite instability and MLH1 methylation in endometrial tumors (P<0.001). Furthermore, hypermethylation of miR-203 was found in endometrioid and clear endometrial subtype tumors, but not in cervical squamous cell and ovarian carcinomas.
  
  
  CONCLUSIONS
  Hypermethylation of miR-203 is a frequent event in endometrial carcinomas and is strongly associated with microsatellite instability and MLH1 methylation status. Thus, miR-203 methylation level might represent a marker for patients with endometrioid and clear endometrial sub-cancers.
authors: Department of Obstetrics and Gynecology, Medical College of Wisconsin, Milwaukee, WI 53226, USA. Electronic address: ywhuang@mcw.edu.
authors: Yi-Wen
authors: YW
authors: Huang
authors: Department of Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
authors: Chieh-Ti
authors: CT
authors: Kuo
authors: Department of Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
authors: Jo-Hsin
authors: JH
authors: Chen
authors: Department of Obstetrics and Gynecology, The Ohio State University, Columbus, OH 43210, USA.
authors: Paul J
authors: PJ
authors: Goodfellow
authors: Department of Molecular Medicine and Cancer Therapy & Research Center, University of Texas Health Science Center, San Antonio, TX 78229, USA.
authors: Tim H-M
authors: TH
authors: Huang
authors: Department of Obstetrics and Gynecology, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
authors: Janet S
authors: JS
authors: Rader
authors: Department of Obstetrics and Gynecology, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
authors: Denise S
authors: DS
authors: Uyar
mesh_terms: D018262:Adenocarcinoma, Clear Cell / Q000235:genetics / Q000378:metabolism; D014408:Biomarkers, Tumor; D018269:Carcinoma, Endometrioid / Q000235:genetics* / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000378:metabolism; D016022:Case-Control Studies; D045744:Cell Line, Tumor; D019175:DNA Methylation; D016889:Endometrial Neoplasms / Q000235:genetics* / Q000378:metabolism; D004717:Endometrium / Q000378:metabolism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D035683:MicroRNAs / Q000378:metabolism*; D053842:Microsatellite Instability; D010051:Ovarian Neoplasms / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D055751:SOXC Transcription Factors / Q000235:genetics* / Q000378:metabolism; D002583:Uterine Cervical Neoplasms / Q000235:genetics / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; C546703:MIRN203 microRNA, human; C578248:MIRN219 microRNA, human; C579843:MIRN596 microRNA, human; C588068:MIRN618 microRNA, human; D035683:MicroRNAs; C083431:SOX4 protein, human; D055751:SOXC Transcription Factors
keywords: DNA methylation; Endometrial carcinoma; SOX4; miR-203