RESUMO
BACKGROUND: Despite recent advances in multimodality therapy, the prognosis for invasive esophageal cancer is poor, with five years survival rate generally below 10%. Therefore, immunotherapy is considered as one of the new therapeutic modality in esophageal cancer. However, expression of tumor specific antigen in tumor tissue should be necessary for immunotherapy of tumor. This study is to clarify that mutant p53 protein and MAGE-3 gene product is expressed in esophageal cancer specifically and they can be played a role of prognostic factors in esophageal cancer. MATERIAL AND METHOD: Expression of mutant p53 protein and MAGE-3 gene products in formalin fixed, paraffin embedded samples of 79 patients with primary squamous cell carcinoma of the esophagus, who undewent esophageal resection, were analyzed immunohistochemically with DO-7 monoclonal antibody and anti- MAGE-3 antibody. Twenty cases of esophageal normal mucosa and 20 cases of leiomyoma which is a benign tumor of esophagus, were used as control groups. Immunoreactivities of mutant p53 and MAGE-3 gene product in esophageal cancer tissues were analyzed and the relationships between immunoreactivity of mutant p53 protein, MAGE-3 gene product and AJCC stage of esophageal cancer were determined by the Chi-square test. RESULT: Positive immunoreactivity of mutant p53 and MAGE-3 gene product were each of 41/79(51.9%), 48/79(60.8%) in esophageal cancer tissue, but 0% in normal mucosa and leiomyoma of esophagus(p<0.001). Both immunoreactivity of mutant p53 and MAGE-3 gene products were not related to AJCC stage of esophageal cancer(p=0.193, p=0.452). There was not correlation between expression of mutant p53 protein and MAGE-3 gene product in esophageal cancer(p=0.697). CONCLUSION: Mutant p53 and MAGE-gene product cannot be a prognostic factor in squamous cell carcinoma of esophagus, but mutant p53 and MAGE-3 gene product is expressed in squamous cell carcinoma of the esophagus specifically, so esophageal cancer can be target for cytotoxic T lymphocyte in anticancer immunotherapy.