title: Using biopsy materials to detect mutations in gastrointestinal tumors.
abstract: Because endoscopic examinations are a crucial first step in the diagnosis of carcinomas, we have analyzed point mutations of the c-K-ras and p53 genes using biopsied samples. There is no previous report of such an approach, using only biopsied materials. We analyzed point mutations of the c-K-ras and p53 genes using 60 colorectal and 31 gastric tumor biopsy specimens. None of the gastric and seven of the colorectal tumors had mutations of the c-K-ras gene. p53 gene mutations were detected in six gastric carcinomas [two out of 11 intramucosal carcinomas (18.2%) and four out of 11 invasive carcinomas (36.4%)]. Eight of 15 invasive colorectal carcinomas (53.3%) showed point mutations in the p53 gene. Although point mutation frequencies in this study were relatively low when compared with previous reports in which surgical samples were used, our study shows that biopsied specimens are adequate and useful for analysis of gene point mutations.
authors.affiliation: First Department of Internal Medicine, Faculty of Medicine, Tokyo Medical, and Dental University, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Hosoi
authors.forename: S
authors.initials: S
authors.lastname: Hirosawa
authors.forename: K
authors.initials: K
authors.lastname: Yamamoto
authors.forename: T
authors.initials: T
authors.lastname: Ohkusa
authors.forename: N
authors.initials: N
authors.lastname: Aoki
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D000236:Adenoma / Q000235:genetics* / Q000473:pathology; D001483:Base Sequence; D001706:Biopsy; D003062:Codon; D015179:Colorectal Neoplasms / Q000235:genetics / Q000473:pathology; D004252:DNA Mutational Analysis; D004724:Endoscopy; D005770:Gastrointestinal Neoplasms / Q000235:genetics* / Q000473:pathology; D016158:Genes, p53 / Q000235:genetics*; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D018807:Polymorphism, Single-Stranded Conformational; D013274:Stomach Neoplasms / Q000235:genetics / Q000473:pathology
chemical_list: D003062:Codon