title: Differential gene expression profiles of metastases in paired primary and metastatic colorectal carcinomas.
abstract: METHODS
  Despite the overwhelming clinical significance of metastases, the cellular and molecular mechanisms involved are largely unknown. In order to define significant differences between primary colon carcinomas and their metastases, we analyzed gene expression profiles of 12 sets of triple-paired tissues using 19 K human oligonucleotide microarrays. A total of 36 microarray experiments were analyzed by unsupervised two-way hierarchical clustering and multi-dimensional scaling (MDS).
  
  
  RESULTS
  Both methods completely distinguished normal mucosa from carcinoma, but failed to demonstrate a complete classification of primary and metastatic carcinomas. We found a separable tendency to be classified into the primary and metastatic colon carcinomas by MDS. In supervised hierarchical clustering, we identified 80 genes that were differentially expressed between paired primary and metastatic colon carcinomas. The 80 identified genes also successfully distinguished three validation sets of primary and lung-metastatic colon carcinomas. A specific set of genes was identified that distinguished the metastasis from the corresponding primary tumor in nearly half of the metastases analyzed.
  
  
  CONCLUSIONS
  We suggest that a more accurate model of the metastatic potential is based on a global tumor expression pattern along with the appearance of distinct metastatic variants. This molecular profiling may be useful for the future study of colon cancer metastasis.
authors.affiliation: Brain Korea 21 Projects for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Kwi Hye
authors.initials: KH
authors.lastname: Koh
authors.forename: Hwanseok
authors.initials: H
authors.lastname: Rhee
authors.forename: Hyun Ju
authors.initials: HJ
authors.lastname: Kang
authors.forename: Eungi
authors.initials: E
authors.lastname: Yang
authors.forename: Kwon Tae
authors.initials: KT
authors.lastname: You
authors.forename: Hanna
authors.initials: H
authors.lastname: Lee
authors.forename: Byung Soh
authors.initials: BS
authors.lastname: Min
authors.forename: Nam Kyu
authors.initials: NK
authors.lastname: Kim
authors.forename: Suk Woo
authors.initials: SW
authors.lastname: Nam
authors.forename: Hoguen
authors.initials: H
authors.lastname: Kim
mesh_terms: D000368:Aged; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology / Q000628:therapy; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics* / Q000556:secondary / Q000628:therapy; D008297:Male; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis