title: Genome-wide copy number changes and CD133 expression characterized distinct subset of colon polyps: differentiation between incidental polyps and cancer-associated polyps.
abstract: OBJECTIVE
  Colorectal polyps are generally believed to be the precursors of colorectal cancers (CRC); however, the proportion and speed of progression differed widely in different subsets of polyps. Using microarray-based comparative genomic hybridization (aCGH) platform and CD133 immunostaining, we characterized colon polyps according to their association with CRC that developed in the same individual.
  
  
  METHODS
  aCGH was performed to unveil genomic changes in 18 cancer-synchronous polyps (CSP), and 9 cancer-preceding polyps (CPP), together with their corresponding cancers and 16 cases of incidental polyps (IP), were examined for comparison. aCGH profiles were analyzed to determine the clonal relationship (CR) between the paired adenoma and carcinoma. CD133 expressions in each subset of polyps were quantified by immunohistochemistry (IHC) staining.
  
  
  RESULTS
  Progressive genomic changes were observed from IP, CSP/CPP to CRC; they encompass an entire chromosomal region in IP and sub-chromosomal region in CSP/CPP and CRC. CR analyses demonstrated that 50 % of CSP and 67 % of CPP were clonally related to the concurrent or later developed carcinomas, respectively. The CD133 expression levels were significantly higher in CSP/CPP than those in IP (P < 0.0001) and even higher in CSP/CPP that were clonally related to their corresponding carcinomas than CSP/CPP that were unrelated (P < 0.05).
  
  
  CONCLUSIONS
  There were more genomic changes in CSP/CPP than IP; more than half of the CSP/CPP were clonally related to the corresponding carcinomas. Genomic changes at sub-chromosomal regions and/or high CD133 expression were associated with CSP/CPP and highlighted their carcinogenic potential.
authors.affiliation: Department of Education and Research, Taipei City Hospital, Taipei, Taiwan.
authors.forename: Chih-Yung
authors.initials: CY
authors.lastname: Yang
authors.affiliation: Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Ju-Yu
authors.initials: JY
authors.lastname: Tseng
authors.affiliation: VYM Genome Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chian-Feng
authors.initials: CF
authors.lastname: Chen
authors.affiliation: Department of Pathology, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Teh-Ying
authors.initials: TY
authors.lastname: Chou
authors.affiliation: Department of Pathology, Tri-Service General Hospital, Taipei, Taiwan.
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Gao
authors.affiliation: VYM Genome Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chia-Ling
authors.initials: CL
authors.lastname: Hua
authors.affiliation: Department of Education and Research, Taipei City Hospital, Taipei, Taiwan.|Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan.|VYM Genome Research Center, National Yang-Ming University, Taipei, Taiwan.|School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chi-Hung
authors.initials: CH
authors.lastname: Lin
authors.affiliation: School of Medicine, National Yang-Ming University, Taipei, Taiwan.|Division of Colon & Rectal Surgery, Department of Surgery, Taipei Veterans General Hospital, Pei-Tou, Taipei, 11217, Taiwan.
authors.forename: Jen-Kou
authors.initials: JK
authors.lastname: Lin
authors.affiliation: School of Medicine, National Yang-Ming University, Taipei, Taiwan. jkjiang@vghtpe.gov.tw.|Division of Colon & Rectal Surgery, Department of Surgery, Taipei Veterans General Hospital, Pei-Tou, Taipei, 11217, Taiwan. jkjiang@vghtpe.gov.tw.
authors.forename: Jeng-Kai
authors.initials: JK
authors.lastname: Jiang
mesh_terms: D000071916:AC133 Antigen; D000236:Adenoma / Q000235:genetics; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000235:genetics* / Q000378:metabolism; D002277:Carcinoma / Q000235:genetics; D003111:Colonic Polyps / Q000235:genetics* / Q000378:metabolism; D055028:Comparative Genomic Hybridization; D005260:Female; D015870:Gene Expression; D006023:Glycoproteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010455:Peptides / Q000235:genetics* / Q000378:metabolism; D011446:Prospective Studies; D012307:Risk Factors
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides
keywords: Array CGH; CD133; Colorectal cancer; Colorectal polyp