p53 gene mutations in primary gastric cancer

摘要

AIMS p53 gene is one of the focuses in the study of tumour suppressor genes. So far, there is still controversy about the relationship between p53 alterations and clinicolpathological parameters of gastic cancers such as macroscopic classification, stage, degree of differentiation, depth of tumour invasion and lymphonod metastasis. Tamura has reported that p53 gene mutations mainly occur in the aneuploid tumours. But in China, nothing is reported in this field of study. Our aim is to analyze the relationship between p53 gene mutations and these parameters including DNA ploidy in Chinese primary gasrtic cancers. METHODS Mutations of the p53 gene in exon5 - 8 were examined in 20 cases of primary gasric cancer by PCR - SSCP (Polymerase - chain - reaction - single - strand - conformation - polymorphism)analysis. RESULTS Mutations were detected in 8(40%) cases: 2 cases in exonS- 6, 2 cases in exon? , 4 cases in exonS.These mutations were detected from stage 0 to stage Ⅲ. No significant association was found between p53 gene mutations and the clinicopathdogical parameters such as macroscopic classification , degree of histological differentiation , depth of tumour invasion and lymphonod metastasis. In addition, 66.7% (6 of 9) of aneuploid tumours had p53 mutations and only 18.2% (2 of 11 )of diploid tumours had mutations. CONCLUSIONS These results suggest that p53 gene mutations are related to DNA ploidy alterations and that p53 gene is one of the important tumour suppressor genes in human gastric cancer.