The role of ras gene mutation in gastric cancer and precancerous lesions.
Abnormality of ras gene family was studied in a total of 206 cases of gastric cancer and precancerous lesions by PCR-RFLP, PCR-SSCP and DNA sequencing. The results showed that mutation rate of H-ras 12 codon in metaplasia, atypical hyperplasia, early-stage cancer and advanced cancer was 16.7%, 31.2%, 50.0%, and 32.2%, respectively. In the groups of superficial gastritis and normal controls, no mutation were detected in codon 12 of ras. Mutations of H-ras 61 codon and N-ras 12 codon in various groups were the same as those in normal control. K-ras 12 codon mutation was detected in only 2 cases of gastric cancer by using PCR-SSCP, but it was not detected by DNA sequencing, which may be polymorphism. All H-ras 12 codon mutations were G-->T mutation. There were significant difference between the groups of metaplasia, dysplasia, gastric carcinoma and normal control group (P < 0.05, P < 0.01, P < 0.01, respectively). It was concluded that H-ras 12 codon mutation was an early event and may play an important role in gastric carcinogenesis. Although K-ras, N-ras mutation rates are high in colon cancer and leukemia, it seems to bear no relationship with gastric cancer.
Hao
Y
Y
Department of Gastroenterology, Xiehe Hospital, Tongji Medical University, Wuhan.
Zhang
J
J
Lu
Y
Y
Yi
C
C
Qian
W
W
Cui
J
J
D005753:Gastric Mucosa / Q000378:metabolism / Q000473:pathology; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D007414:Intestinal Neoplasms / Q000235:genetics; D008679:Metaplasia; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D018807:Polymorphism, Single-Stranded Conformational; D011230:Precancerous Conditions / Q000235:genetics*; D013274:Stomach Neoplasms / Q000235:genetics*