title: Mutation of ras oncogene in gastric adenocarcinoma: association with histological phenotype.
abstract: In order to explore the role of ras oncogene in gastric carcinomas from Korean patients, we examined the frequency of point mutations all three ras oncogenes (Ki-, Ha-, and N-ras). A total of 57 DNA samples were prepared from 3 gastric carcinoma cell lines, 10 malignant ascites, and 44 frozen gastric tumor tissues. Exons 1 and 2 of each ras oncogene were amplified by polymerase chain reaction (PCR), and analyzed by single strand conformation polymorphism (SSCP) and direct sequencing. Mutated ras genes were detected in 6 out of 57 samples (10%). One cell line and 2 tumors showed a mutation at exon 1 of Ki-ras. N-ras mutations were also detected at exon 1 of 3 tumors. Histologically, all the ras mutation cases exhibited a diffuse phenotype. In summary, we performed a comprehensive analysis to investigate the mutation of all three ras oncogenes in gastric carcinoma. The results demonstrate infrequent mutations of Ki- and N-ras which may favor the development of diffuse type gastric carcinomas, implicating a different genetic pathway in diffuse and intestinal type gastric carcinomas.
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Korea.
authors.forename: T Y
authors.initials: TY
authors.lastname: Kim
authors.forename: Y J
authors.initials: YJ
authors.lastname: Bang
authors.forename: W S
authors.initials: WS
authors.lastname: Kim
authors.forename: S H
authors.initials: SH
authors.lastname: Kang
authors.forename: K U
authors.initials: KU
authors.lastname: Lee
authors.forename: K J
authors.initials: KJ
authors.lastname: Choe
authors.forename: N K
authors.initials: NK
authors.lastname: Kim
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D011905:Genes, ras; D006801:Humans; D009154:Mutation; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D013274:Stomach Neoplasms / Q000235:genetics* / Q000473:pathology