title: Circulating tumor cells and aberrant methylation as tumor markers in patients with esophageal cancer.
abstract: BACKGROUND
  This study was designed to compare the detection rates of conventional tumor markers with two molecular diagnostic approaches on blood samples from patients with esophageal squamous cell cancer.
  
  
  METHODS
  Preoperative blood samples were obtained from 44 esophageal cancer patients and were subjected to CEA-specific reverse transcriptase-polymerase chain reaction (RT-PCR) assay and methylation-specific polymerase chain reaction (MSP) assay for p16, E-cadherin and RARbeta genes.
  
  
  RESULTS
  Circulating tumor cells were detected in 12 patients (27%); 14 patients (32%) had aberrant methylation in the promoter region of at least one gene (6, 4 and 4 patients, for p16, E-cadherin and RARbeta, respectively). No abnormality was detected by either assay in control plasmas. Altogether, 23 patients (53%) had a positive result in either molecular assay. There was no correlation between either assay result and those of conventional serum markers.
  
  
  CONCLUSIONS
  The RT-PCR and MSP assays can serve as complementary markers for screening and monitoring esophageal cancer patients.
authors.affiliation: Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kawaramachihirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan.
authors.forename: Daito
authors.initials: D
authors.lastname: Ikoma
authors.forename: Daisuke
authors.initials: D
authors.lastname: Ichikawa
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ueda
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Tani
authors.forename: Haruhisa
authors.initials: H
authors.lastname: Tomita
authors.forename: Soujin
authors.initials: S
authors.lastname: Sai
authors.forename: Shojiro
authors.initials: S
authors.lastname: Kikuchi
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Fujiwara
authors.forename: Eigo
authors.initials: E
authors.lastname: Otsuji
authors.forename: Hisakazu
authors.initials: H
authors.lastname: Yamagishi
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D015820:Cadherins / Q000235:genetics; D002272:Carcinoembryonic Antigen / Q000235:genetics*; D002294:Carcinoma, Squamous Cell / Q000097:blood / Q000175:diagnosis* / Q000235:genetics; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics; D019175:DNA Methylation; D004938:Esophageal Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008875:Middle Aged; D009360:Neoplastic Cells, Circulating / Q000378:metabolism / Q000473:pathology*; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018168:Receptors, Retinoic Acid / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; D015820:Cadherins; D002272:Carcinoembryonic Antigen; D019941:Cyclin-Dependent Kinase Inhibitor p16; D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; C082925:retinoic acid receptor beta