title: Discrepancies between the K-ras mutational status of primary colorectal cancers and corresponding liver metastases are found in codon 13.
abstract: K-ras mutation status has remained elusive in the metastatic liver tumors of colorectal cancer (CRC) in contrast to the primary CRC tumors. In this study, K-ras mutational status of the primary and corresponding liver metastatic tumors was investigated in the 43 CRC patients. Codons 12 and 13 of K-ras were directly sequenced, and a K-ras mutation was evident in 17 cases (39.5%). In 6 cases, the K-ras mutation was evident only in the liver metastasis, but not in the primary CRC, where the mutation was found in codon 13. This discrepancy between primary and metastatic lesions with regard to codon 13 of the K-ras gene may explain the clinical discrepancy of EGFR antibody therapy. In conclusion, the current data may lead to the development of personalized medicine for recurrent CRC, although further validation study is still required.
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawamata
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Japan. Electronic address: keishi23@med.kitasato-u.ac.jp.
authors.forename: Keishi
authors.initials: K
authors.lastname: Yamashita
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Kojo
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Ushiku
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Ooki
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Watanabe
mesh_terms: D003062:Codon; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D004252:DNA Mutational Analysis; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins / Q000235:genetics*
chemical_list: D003062:Codon; C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins
keywords: Codon 13; Colorectal cancer; K-ras mutation; Liver metastasis; Micrometastasis