[High frequency mutation of p53 gene in human gastric cancer and precancerous lesions].
OBJECTIVE
To determine the frequency and type of p53 gene mutation with the progression of human gastric carcinogenesis.


METHODS
Single strand conformation polymorphism (SSCP) and DNA sequencing were performed on 56 biopsied tissues, including gastric cancer (n = 23), dysplasia (Dys, n = 16) and intestinal metaplasia (IM, n = 17).


RESULTS
p53 gene mutation was detected in 60.1% of cancer, 31.3% of Dys and 11.8% of IM. Mutations covered exon 5-8 without hot spot. GC-->AT transitions (30.4%) and GC-->TA transversions (26.1%) were the major patterns of p53 mutation. Missense (73.9%) and frame shift mutations covered 86.9% of all mutations.


CONCLUSIONS
In the process of human gastric carcinogenesis, multiple factors are involved in p53 gene mutations. The mutation rate increases with the progression of malignant changes in the gastric mucosa. Missense and frame shift mutations are possibly the major cause of p53 inactivation.
Beijing Institute for Cancer Research, School of Oncology, Beijing Medical University.
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Li
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Lü
D000230:Adenocarcinoma / Q000235:genetics; D000328:Adult; D000368:Aged; D005091:Exons; D005260:Female; D016158:Genes, p53; D006801:Humans; D008297:Male; D008679:Metaplasia / Q000235:genetics; D008875:Middle Aged; D017354:Point Mutation; D018807:Polymorphism, Single-Stranded Conformational; D011230:Precancerous Conditions / Q000235:genetics*; D013270:Stomach / Q000473:pathology; D013274:Stomach Neoplasms / Q000235:genetics*