title: Frequency and spectrum of c-Ki-ras mutations in human sporadic colon carcinoma, carcinomas arising in ulcerative colitis, and pancreatic adenocarcinoma.
abstract: Sporadic colon carcinomas, carcinomas arising in chronic ulcerative colitis, and pancreatic adenocarcinomas have been analyzed for the presence of c-Ki-ras mutations by a combination of histological enrichment, cell sorting, polymerase chain reaction, and direct sequencing. Although 60% (37/61) of sporadic colon carcinomas contained mutations in codon 12, only 1 of 17 specimens of dysplasia or carcinoma from ulcerative colitis patients contained c-Ki-ras mutations, despite a high frequency of aneuploid tumors. In contrast, a higher percentage (16/20 = 80%) of pancreatic adenocarcinomas contained mutations in c-Ki-ras 2, despite a lower frequency of DNA aneuploidy in these neoplasms. Moreover, the spectrum of mutations differed between sporadic colon carcinoma, where the predominant mutation was a G to A transition, and pancreatic carcinomas, which predominantly contained G to C or T transversions. These results suggest that the etiology of ras mutations is different in these three human neoplasms.
authors.affiliation: Department of Pathology, University of Washington School of Medicine, Seattle 98195.
authors.forename: G C
authors.initials: GC
authors.lastname: Burmer
authors.forename: P S
authors.initials: PS
authors.lastname: Rabinovitch
authors.forename: L A
authors.initials: LA
authors.lastname: Loeb
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics*; D000782:Aneuploidy; D002277:Carcinoma / Q000150:complications / Q000235:genetics*; D003062:Codon; D003093:Colitis, Ulcerative / Q000150:complications* / Q000235:genetics; D003106:Colon / Q000473:pathology; D003110:Colonic Neoplasms / Q000150:complications / Q000235:genetics*; D004249:DNA Damage; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000235:genetics; D005434:Flow Cytometry; D011905:Genes, ras; D006801:Humans; D009154:Mutation; D010190:Pancreatic Neoplasms / Q000235:genetics*; D016133:Polymerase Chain Reaction; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics*
chemical_list: D003062:Codon; D004273:DNA, Neoplasm; C501009:HRAS protein, human; D016283:Proto-Oncogene Proteins p21(ras)