title: K-ras oncogene activation in adenocarcinoma of the human pancreas. A study of 82 carcinomas using a combination of mutant-enriched polymerase chain reaction analysis and allele-specific oligonucleotide hybridization.
abstract: We examined 82 surgically resected or biopsied, formalin-fixed, paraffin-embedded primary adenocarcinomas of the pancreas for the presence of activating point mutations in codon 12 of the K-ras oncogene. Mutations were detected using primer-mediated, mutant-enriched, polymerase chain reaction-restriction fragment length polymorphism analysis and characterized further by allele-specific oligonucleotide hybridization. This combination of mutant-enriched polymerase chain reaction-restriction fragment length polymorphism analysis and allele-specific oligonucleotide hybridization results in a rapid and sensitive characterization of the mutations in codon 12 of K-ras. Sixty-eight (83%) of the 82 carcinomas examined harbored a point mutation. Of the 68 mutations, 33 (49%) were guanine to adenine transitions, 27 (39%) were guanine to thymine transversions, and eight (12%) were guanine to cytosine transversions. Mutations were found in carcinomas of the head (61 of 75, 81%) as well as in carcinomas of the body or tail (seven of seven, 100%) of the pancreas. The overall prevalence of K-ras point mutations in adenocarcinomas of the pancreas obtained from patients who smoked cigarettes at some point during their lives (88%; 86% in current smokers and 89% in ex-smokers) was greater than that seen in pancreatic adenocarcinomas from patients who never smoked cigarettes (68%, P = 0.046). The presence of K-ras point mutations did not correlate with tumor ploidy, tumor proliferating index, or patient survival. These results demonstrate that primer-mediated, mutant-enriched polymerase chain reaction-restriction fragment length polymorphism analysis combined with allele-specific oligonucleotide hybridization can be used to detect and characterize mutations in codon 12 of the K-ras oncogene in formalin-fixed, paraffin-embedded tissues, and the results confirm that activating point mutations in codon 12 of the K-ras oncogene occur frequently in adenocarcinomas of the pancreas.
authors.affiliation: Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: R H
authors.initials: RH
authors.lastname: Hruban
authors.forename: A D
authors.initials: AD
authors.lastname: van Mansfeld
authors.forename: G J
authors.initials: GJ
authors.lastname: Offerhaus
authors.forename: D H
authors.initials: DH
authors.lastname: van Weering
authors.forename: D C
authors.initials: DC
authors.lastname: Allison
authors.forename: S N
authors.initials: SN
authors.lastname: Goodman
authors.forename: T W
authors.initials: TW
authors.lastname: Kensler
authors.forename: K K
authors.initials: KK
authors.lastname: Bose
authors.forename: J L
authors.initials: JL
authors.lastname: Cameron
authors.forename: J L
authors.initials: JL
authors.lastname: Bos
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D001483:Base Sequence; D003062:Codon; D005260:Female; D005500:Follow-Up Studies; D015972:Gene Expression Regulation, Neoplastic; D011905:Genes, ras; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D010190:Pancreatic Neoplasms / Q000235:genetics* / Q000473:pathology; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D015996:Survival Rate
chemical_list: D003062:Codon; D015345:Oligonucleotide Probes