title: CD133-positive tumor cell content is a predictor of early recurrence in colorectal cancer.
abstract: BACKGROUND
  The aims of this study were to demonstrate the tumorigenicity of CD133+ colon cancer cells in vitro, analyze the correlations between spheroid formation and clinicopathologic variables, and screen for overexpressed genes in CD133+ colon cancer stem cells. Moreover, the aim of this study was to establish a living tumor tissue bank using surgically resected specimens.
  
  
  METHODS
  Using LoVo cell line, we isolated CD133+ cells and performed clonogenic assay and animal experiment to test tumorigenicity of CD133+ cells. Twenty-nine surgical samples were freshly collected from 27 patients who received curative or palliative surgery, and the samples were mechanically and enzymatically dissociated into single cells.
  
  
  RESULTS
  We confirmed the enhanced tumorigenicity of CD133+ cells isolated from LoVo cell line both in vitro and in vivo. Of these 29 samples, 8 (28%) contained >3% CD133+ cells. Sphere formation was significantly higher in samples from patients with lymphatic invasion than in those without lymphatic invasion [54.5% (6/11) vs. 12.5% (2/16); P=0.033] and in samples containing >3% of CD133+ cells than in those containing ≤3% of CD133+ cells [36.4% (4/11) vs. 0% (0/16); P=0.019].
  
  
  CONCLUSIONS
  These findings indicate that CD133 is a valid marker for identifying cancer stem cells from fresh surgically resected colorectal cancer tissues. Furthermore, we successfully established a living tumor tissue bank using surgically resected colorectal tissues with a viability of >70%.
authors.affiliation: 1 Division of Hematology-Oncology, Department of Medicine, 2 Department of Pathology, 3 Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Sung Hee
authors.initials: SH
authors.lastname: Lim
authors.affiliation: 1 Division of Hematology-Oncology, Department of Medicine, 2 Department of Pathology, 3 Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jiryeon
authors.initials: J
authors.lastname: Jang
authors.affiliation: 1 Division of Hematology-Oncology, Department of Medicine, 2 Department of Pathology, 3 Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Joon Oh
authors.initials: JO
authors.lastname: Park
authors.affiliation: 1 Division of Hematology-Oncology, Department of Medicine, 2 Department of Pathology, 3 Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kyoung-Mee
authors.initials: KM
authors.lastname: Kim
authors.affiliation: 1 Division of Hematology-Oncology, Department of Medicine, 2 Department of Pathology, 3 Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Seung Tae
authors.initials: ST
authors.lastname: Kim
authors.affiliation: 1 Division of Hematology-Oncology, Department of Medicine, 2 Department of Pathology, 3 Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Young Suk
authors.initials: YS
authors.lastname: Park
authors.affiliation: 1 Division of Hematology-Oncology, Department of Medicine, 2 Department of Pathology, 3 Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jeeyun
authors.initials: J
authors.lastname: Lee
authors.affiliation: 1 Division of Hematology-Oncology, Department of Medicine, 2 Department of Pathology, 3 Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hee Cheol
authors.initials: HC
authors.lastname: Kim
keywords: CD133; cancer stem cell; colorectal cancer