title: Cancer stem cell marker in circulating tumor cells: expression of CD44 variant exon 9 is strongly correlated to treatment refractoriness, recurrence and prognosis of human colorectal cancer.
abstract: OBJECTIVE
  The expression of the CD44 variant exon 9 (CD44v9) was investigated in order to elucidate its significance for cancer stem cells in circulating human colorectal cancer cells (CTCs).
  
  
  METHODS
  After peripheral blood was drawn from patients with colorectal cancer, CTCs were collected. Using the reverse transcription-polymerase chain reaction method, we examined the relationship between expression of CD44v9 mRNA and prognosis.
  
  
  RESULTS
  In 60 out of 150 patients with colorectal cancer, expression of CD44v9 mRNA was positive in CTCs. In patients with stage III disease, the 5-year survival rate was 89% for patients with negative CD44v9 expression, whereas it was 52.4% in patients with positive expression (p<0.05). In patients with stage IV unresectable cancer, the 2-year survival rate was 70.1% in cases with CD44v9-negative expression and 33.3% in cases of positive expression (p<0.05).
  
  
  CONCLUSIONS
  CD44v9 mRNA in the CTCs of colorectal cancer is useful as a factor predicting recurrence, prognosis, and treatment efficacy.
authors.affiliation: First Department of Surgery, University of Fukui, Fukui, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Katoh
authors.affiliation: First Department of Surgery, University of Fukui, Fukui, Japan tgoi@u-fukui.ac.jp.
authors.forename: Takanori
authors.initials: T
authors.lastname: Goi
authors.affiliation: First Department of Surgery, University of Fukui, Fukui, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Naruse
authors.affiliation: First Department of Surgery, University of Fukui, Fukui, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Ueda
authors.affiliation: First Department of Surgery, University of Fukui, Fukui, Japan.
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Kurebayashi
authors.affiliation: First Department of Surgery, University of Fukui, Fukui, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Nakazawa
authors.affiliation: First Department of Surgery, University of Fukui, Fukui, Japan.
authors.forename: Youhei
authors.initials: Y
authors.lastname: Kimura
authors.affiliation: First Department of Surgery, University of Fukui, Fukui, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Hirono
authors.affiliation: First Department of Surgery, University of Fukui, Fukui, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Yamaguchi
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D019008:Drug Resistance, Neoplasm; D005091:Exons; D005260:Female; D015870:Gene Expression; D006801:Humans; D018960:Hyaluronan Receptors / Q000235:genetics / Q000378:metabolism*; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000378:metabolism* / Q000473:pathology; D009360:Neoplastic Cells, Circulating / Q000378:metabolism*; D014411:Neoplastic Stem Cells / Q000378:metabolism*; D011379:Prognosis; D016016:Proportional Hazards Models; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; C497483:CD44 protein, human; D018960:Hyaluronan Receptors; D012333:RNA, Messenger
keywords: CD44 variant exon 9; Colorectal cancer; circulating tumor cells