Clinical Significance Of Expressions Of P53, C-erbB-2 And Ras Genes In Gastric Cancer

Objective:Gastric cancer is a chronic proliferative disease with multiple genetic and epigenetic alterations; that is, it is a disease with altered gene expression, including many primary cancer genes, and anti-cancer genes. The expression of anti-cancer gene p53 and primary cancer genes C-erbB-2 and Ras affect closely on the development of gastric cancer, but the most studies about the relationship of the expression of cancer genes with the development of gastric cancer limited on single cancer gene, the results are controversial. This research is to analyzed the expression of p53, C-erbB-2 and Ras genes in gastric cancer and normal gastric tissue by using immunohistochemical(SP) method at the same time, in conjunction with the clinicopathological features. Combined analyses of the expression of p53, C-erbB-2 and Ras genes was used to determine the correlation between p53, C-erbB-2 and Ras, and the relation of expression of p53, C-erbB-2 and Ras genes with the development, progression, metastasis and prognosis of gastric cancer. The aim of this study was also to search for a simple but effective method of molecular pathology for patients with gastric cancer.Methods:This study analyzed the expression of mutant gene p53 and primary cancer genes C-erbB-2, Ras in 82 cases of gastric cancer and 18 cases of normal gastric tissue by using immunohistochemical(SP) method .Positive expression of p53, C-erbB-2 and Ras genes in the gastric cells were observed by microscope, every specimen was observed in ten continuous visual field. The positive expression rate less than 25% was recorded as (-)? the positive expression rate between 25% and 50% was recorded as (+), positive expression rate between 50% and 75% was recorded as (++), positive expression rate more than 75% was recorded as(+++). Evaluation of survival rate was divided into 3 and 5 years survival rate .The statistical date was analyzed by Chi-square test by using SPSS 10.0 , P<0.05 was considered to be significant .Results:1. The expression of p53, C-erbB-2 and Ras genes was more frequently detected in gastric cancer than in normal gastric tissue (P<0.05) .2. The expression of p53 was more frequently detected in gastric cancer with distal metastasis than without distal metastasis (P<0.05) , but it was not significantly different in carcinoma diameter, differentiation degree,invasive depth and lymph node metastasis(P>0.05) .The expression of C-erbB-2 was more frequently detected in gastric cancer with distal metastasis and carcinoma diameter> 4cm than without distal metastasis and carcinoma diameter≤4cm (P<0.05) , but it was not significantly different in differentiation degree, invasive depth and lymph node metastasis(P>0.05) .The expression of Ras was more frequently detected in gastric cancer with carcinoma diameter>4cm than carcinoma diameter≤4cm (P<0.05) , but it was not significantly different in differentiation degree, invasivedepth, lymph node metastasis and distal metastasis (P>0.05) .3. For evaluation of 3 and 5 years survival rate, the positive expression of p53, C-erbB-2 and Ras genes in gastric cancer patients leaded to shorter survival time than the negative expression (P<0.05 and P<0.01).4. The expression of p53 gene was positively related with the expression of C-erbB-2 gene (P<0.05) ,but the expression of p53 gene had no significant relation with the expression of Ras(P>0.05), the expression of C-erbB-2 gene had no significant relation with the expression of Ras(P>0.05).Conclusion:1. The development of gastric cancer is a course affected by anti-cancer gene p53 and primary cancer genes C-erbB-2, Ras .2. The expression of p53, C-erbB-2 and Ras genes had no significant relationship with differentiation degree. The discrimination of differentiation degree in tissue pathology depend on cell shape and tissue structure, not depend on the expression of cancer genes. So the seek after new cancer genes as a molecular pathologic mark for the differentiation degree and needed.3. The expression of p53 and C-erbB-2 was more freq...