title: Cell cycle analysis of the CD133(+) and CD133(-) cells isolated from human colorectal cancer.
abstract: OBJECTIVE
  The CD133 antigen has been identified as a putative stem cell marker in colorectal cancer tissues. The aim of this study was to investigate the cell cycle state of CD133(+) and CD133(-) cells, isolated from primary human colorectal tumors.
  
  
  METHODS
  After mechanical and enzymatic dissociation of the tumor samples, CD133(+) and CD133(-) subsets were identified and separated by magnetic cell sorting. Flow cytometric analysis was performed to compare the cell cycle of both CD133(+) and CD133(-) cells isolated from primary and liver metastatic cancer cells.
  
  
  RESULTS
  The results indicated that CD133(+) cells isolated from both primary and liver metastatic colorectal cancers were found in higher percentage in the G0/G1 phases. However, the CD133(-) cells isolated from primary colorectal cancers were predominantly found in the S and G2/M phases. Surprisingly, the CD133(-) cells isolated from liver metastatic colorectal cancers were mostly found in the G0/G1 phase.
  
  
  CONCLUSIONS
  The present study provides evidence that CD133(+) cells are in a quiescent state in colorectal cancer, representing a mechanism that would at least partially explain chemotherapy resistance and tumor recurrence in post-therapy patients.
authors.affiliation: Department of Immunology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran. marjangh@gmail.com
authors.forename: Marjan
authors.initials: M
authors.lastname: Gharagozloo
authors.forename: Hamid R
authors.initials: HR
authors.lastname: Mirzaei
authors.forename: Bahram
authors.initials: B
authors.lastname: Bagherpour
authors.forename: Abbas
authors.initials: A
authors.lastname: Rezaei
authors.forename: Hamid
authors.initials: H
authors.lastname: Kalantari
authors.forename: Mohammad H
authors.initials: MH
authors.lastname: Sanei
authors.forename: Mohsen
authors.initials: M
authors.lastname: Hosseini
authors.forename: Gholamreza
authors.initials: G
authors.lastname: Mohajeri
authors.forename: Abbas
authors.initials: A
authors.lastname: Tabatabai
authors.forename: Mozaffar
authors.initials: M
authors.lastname: Hashemi
mesh_terms: D000071916:AC133 Antigen; D000368:Aged; D015703:Antigens, CD / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism; D002453:Cell Cycle; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000473:pathology*; D019008:Drug Resistance, Neoplasm; D005260:Female; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D008113:Liver Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D014411:Neoplastic Stem Cells; D010455:Peptides / Q000378:metabolism*
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D014408:Biomarkers, Tumor; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides