title: Detection of circulating tumor cells by p75NTR expression in patients with esophageal cancer.
abstract: BACKGROUND
  The p75 neurotrophin receptor (p75NTR) is a cancer stem cell (CSC) marker in esophageal squamous cell carcinoma (ESCC). This study aimed to assess the use of p75NTR in detecting circulating tumor cells (CTCs) in ESCC.
  
  
  METHODS
  Peripheral blood mononuclear cell expression of epithelial cell adhesion molecule (EpCAM) and p75NTR was detected in 23 ESCC patients (13 received chemo- or chemoradiotherapy and 10 received curative surgery) and 10 healthy controls by flow cytometry.
  
  
  RESULTS
  EpCAM+p75NTR+ cell counts (average±SD) were significantly higher in patients (n=23, 16.0±18.3) compared to controls (n=10, 0.4±0.9, p=0.013). The sensitivity and specificity to differentiate ESCC patients from controls were 78.3 and 100% (cut-off value 4.0), respectively. EpCAM+p75NTR+, but not EpCAM+p75NTR- cell counts, correlated with clinically diagnosed distant metastasis (n=13, p=0.006) and pathological venous invasion in resected primary tumors (n=10, p=0.016). Malignant cytology was microscopically confirmed in isolated EpCAM+p75NTR+ cells with immunocytochemical double staining.
  
  
  CONCLUSIONS
  p75NTR is suggested to be a useful marker for clinically significant CTCs, which exhibit highly metastatic features in ESCC.
authors.affiliation: Department of Surgery and Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama City, Toyama, 930-0194, Japan. tetsuji-yama@blue.ocn.ne.jp.
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: Department of Surgery and Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama City, Toyama, 930-0194, Japan. okumura@med.u-toyama.ac.jp.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Okumura
authors.affiliation: Department of Surgery and Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama City, Toyama, 930-0194, Japan. hrnkths@med.u-toyama.ac.jp.
authors.forename: Katsuhisa
authors.initials: K
authors.lastname: Hirano
authors.affiliation: Department of Surgery and Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama City, Toyama, 930-0194, Japan. toruwatanabetoru@yahoo.co.jp.
authors.forename: Toru
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Department of Surgery and Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama City, Toyama, 930-0194, Japan. naga0103@med.u-toyama.ac.jp.
authors.forename: Takuya
authors.initials: T
authors.lastname: Nagata
authors.affiliation: Department of Nanobio Drug Discovery, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimo-Adachi-cho, Sakyo-ku, Kyoto, 606-8501, Japan. yshimada@pharm.kyoto-u.ac.jp.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Shimada
authors.affiliation: Department of Surgery and Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama City, Toyama, 930-0194, Japan. ktsukada@med.u-toyama.ac.jp.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Tsukada
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D002294:Carcinoma, Squamous Cell / Q000097:blood / Q000473:pathology* / Q000628:therapy; D003131:Combined Modality Therapy; D004938:Esophageal Neoplasms / Q000097:blood / Q000473:pathology* / Q000628:therapy; D005260:Female; D005434:Flow Cytometry; D005500:Follow-Up Studies; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D009419:Nerve Tissue Proteins / Q000097:blood*; D011379:Prognosis; D017475:Receptors, Nerve Growth Factor / Q000097:blood*
chemical_list: D014408:Biomarkers, Tumor; C484065:NGFR protein, human; D009419:Nerve Tissue Proteins; D017475:Receptors, Nerve Growth Factor