P53 Gene Mutation, Tumor p53 Protein Overexpression, and Serum Anti-p53 Antibody in Patients with Gastric Cancer

Abstract

【Purpose: The clinical implication of p53 mutation in gastric cancer is still unclear, as shown by the discordant results that continue to be reported in the literature. Materials and Methods: To assess p53 gene mutation, tumor p53 overexpression, and serum anti-p53 antibody, we employed a polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis, an immunohistochemistry using monoclonal antibody DO-7, and an enzymelinked immunosorbent assay (ELISA), respectively. Results: Of 169 surgical specimens of gastric cancer, mutation at exon $5\∼8$ of the p53 was identified in 33 ( $19.5\%$ ) and was significantly correlated with lymph node metastasis. Overexpression of p53 was found in 62 specimens ( $36.7\%$ ) and had a significant correlation with tumor differentiation. Serum anti-p53 antibody was positive in 18 patients ( $10.7\%$ ). Twenty-three of the mutated tumors ( $69.7\%$ ) and 39 of the non-mutated tumors ( $28.7\%$ ) displayed immunoreactivity. Twelve of the immunopositive tumors ( $19.4\%$ ) and 6 of the immunonegative tumors produced anti-p53 antibody. These differences were statistically significant (P】