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 metapl...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 Hras 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.展开更多
The point mutation at codons 12 and 61 of c-Ha-ras gene,at codon 12 of N-ras gene and at codons 12 and 13 of K-ras gene was observed in formalin-fixed and paraffin-embedded tissue specimens of 42 cases of gastric canc...The point mutation at codons 12 and 61 of c-Ha-ras gene,at codon 12 of N-ras gene and at codons 12 and 13 of K-ras gene was observed in formalin-fixed and paraffin-embedded tissue specimens of 42 cases of gastric cancer with PCR-RFLP method. It was found that the point mutation at codon 12 of c-Ha-ras occurred in 14 cases out of the 42(33. 3%) and that at codon 12 of K-ras in 2 cases(4. 8%). Statistical analysis showed that the point mutation of ras genes plays an itnportant role in the prognosis for the patients with gastric cancer.展开更多
文摘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 Hras 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.
文摘The point mutation at codons 12 and 61 of c-Ha-ras gene,at codon 12 of N-ras gene and at codons 12 and 13 of K-ras gene was observed in formalin-fixed and paraffin-embedded tissue specimens of 42 cases of gastric cancer with PCR-RFLP method. It was found that the point mutation at codon 12 of c-Ha-ras occurred in 14 cases out of the 42(33. 3%) and that at codon 12 of K-ras in 2 cases(4. 8%). Statistical analysis showed that the point mutation of ras genes plays an itnportant role in the prognosis for the patients with gastric cancer.
