K-ras activation in gastric epithelial tumors in Japanese.
Point mutation in codons 12, 13 and 61 of the K-ras oncogene in gastric epithelial tumors were investigated by polymerase chain reaction from sections of formalin-fixed, paraffin-embedded tissue followed by dot-blot hybridization with mutation-specific oligonucleotide probes. Point mutations were found specifically in four of 20 tumors of intestinal histological subtype; GGT to GAT in three cases and to GTT in one case, all in codon 12 of K-ras. These mutations were also confirmed by direct sequencing. In contrast, none of 11 diffuse-type tumors showed K-ras point mutations. While K-ras point mutations may not be frequent events in gastric tumorigenesis, the similarity of the intestinal-type gastric tumors and colorectal tumors for K-ras point mutations as well as the association of mutations in K-ras with a particular gastric tumor histology implicates K-ras activation in the development of these tumors.
Miki
H
H
Department of Pathology, Kagawa Medical School, Japan.
Ohmori
M
M
Perantoni
A O
AO
Enomoto
T
T
D000236:Adenoma / Q000208:ethnology / Q000235:genetics*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D003062:Codon; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D011905:Genes, ras; D006801:Humans; D007564:Japan / Q000208:ethnology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009154:Mutation; D015345:Oligonucleotide Probes; D016133:Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000208:ethnology / Q000235:genetics*
D003062:Codon; D004273:DNA, Neoplasm; D015345:Oligonucleotide Probes