Mutation, Expression And Function Of E2F-1 In Human Gastric Carcinoma

Object: To search for gene mutation and assay expression of E2F-1 in humangastric carcinoma tissue, observe contribution of E2F-1 to gastric carcinoma cell,fathom the correlation between E2F-1 and gastric carcinoma, and explore thepossible pathway and function of E2F-1 during the development of this tumor.Method: The analytical method of polymerase chain reaction-mediatedsingle-strand conformational polymorphism (PCR-SSCP) was used to assay themutation of E2F-1 gene in tumor tissues and correspondent normal mucosa of 80gastric carcinoma cases, and normal mucosa of 40 normal cases.Immunohistochemistry and statistic method was used to assay the expression ofE2F-1 as well as its correlation with clinical characteristics of the tumor cases. Aeukaryotic expression vector was constructed to transfect a human gastriccarcinoma cell line MKN-45. By colony formation assay and MTS method, a cellgrowth curve was drawn and contribution of over-expressive E2F-1 to this cell linewas surveyed.Result: No Mutation or deletion of E2F-1 gene was found in three groupstissues assayed. The expressive frequency of E2F-1 of tumor tissues was 72.5%(58/80), while correspondent normal mucosa and normal tissues were 30.0% (24/80)and 22.5% (9/40) respectively. The expressive frequency of tumor tissues wasobviously higher than that of correspondent normal mucosa and normal mucosa(P<0.01). There was no significant correlation of E2F-1 with the pathology type,lymphonode metastasis and clinical stage of the tumor (P>0.05). The proliferationof gastric carcinoma cell line MKN-45 was inhibited after being transfected byE2F-1.Conclusion: (1) E2F-1 might be a very stenoplastic and conservative geneduring the development of gastric carcinoma; its mutational incidence was very low.(2) The high expression of E2F-1, which was not necessarily correlated withclinical characteristics of tumor, suggested its close relationship with the neoplasmprogression and persistent high lever after neoplasm genesis, which wasindependent of the tumor stage. (3) Over-expressive E2F-1 would inhibit thegrowth of gastric carcinoma cell line MKN-45.