title: Dysplasia-carcinoma transition specific transcripts in colonic biopsy samples.
abstract: BACKGROUND
  The early molecular detection of the dysplasia-carcinoma transition may enhance the strength of diagnosis in the case of colonic biopsies. Our aims were to identify characteristic transcript sets in order to develop diagnostic mRNA expression patterns for objective classification of benign and malignant colorectal diseases and to test the classificatory power of these markers on an independent sample set.
  
  
  RESULTS
  Colorectal cancer (CRC) and adenoma specific transcript sets were identified using HGU133plus2 microarrays and 53 biopsies (22 CRC, 20 adenoma and 11 normal). Ninety-four independent biopsies (27 CRC, 29 adenoma and 38 normal) were analyzed on microarrays for testing the classificatory power of the discriminatory genes. Array real-time PCR validation was done on 68 independent samples (24 CRC, 24 adenoma and 20 normal). A set of 11 transcripts (including CXCL1, CHI3L1 and GREM1) was determined which could correctly discriminate between high-grade dysplastic adenoma and CRC samples by 100% sensitivity and 88.9% specificity. The discriminatory power of the marker set was proved to be high on independent samples in both microarray and RT-PCR analyses. 95.6% of original and 94.1% of cross-validated samples was correctly classified in discriminant analysis.
  
  
  CONCLUSIONS
  The identified transcripts could correctly characterize the dysplasia-carcinoma transition in biopsy samples, also on a large independent sample set. These markers can establish the basis of gene expression based diagnostic classification of colorectal cancer. Diagnostic RT-PCR cards can become part of the automated routine procedure.
authors.affiliation: 2nd Department of Medicine, Semmelweis University, Budapest, Hungary.
authors.forename: Orsolya
authors.initials: O
authors.lastname: Galamb
authors.forename: Barnabás
authors.initials: B
authors.lastname: Wichmann
authors.forename: Ferenc
authors.initials: F
authors.lastname: Sipos
authors.forename: Sándor
authors.initials: S
authors.lastname: Spisák
authors.forename: Tibor
authors.initials: T
authors.lastname: Krenács
authors.forename: Kinga
authors.initials: K
authors.lastname: Tóth
authors.forename: Katalin
authors.initials: K
authors.lastname: Leiszter
authors.forename: Alexandra
authors.initials: A
authors.lastname: Kalmár
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Tulassay
authors.forename: Béla
authors.initials: B
authors.lastname: Molnár
mesh_terms: D000236:Adenoma / Q000235:genetics* / Q000473:pathology; D002277:Carcinoma / Q000235:genetics* / Q000473:pathology; D002295:Carcinoma, Transitional Cell / Q000235:genetics* / Q000473:pathology; D003106:Colon / Q000473:pathology; D003110:Colonic Neoplasms / Q000235:genetics* / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D006965:Hyperplasia / Q000235:genetics* / Q000473:pathology; D046888:Tissue Array Analysis