Accumulation of p53 in esophageal squamous cell carcinoma

p53 is one of the most important tumor suppressor genes. Mutation of the p5 3 gene can be detected immunohistochemically as over-expression of its prot ein in the nucleus. The p53 gene product is known to regulate cell growth a nd proliferation. Genetic alterations related to the carcinogenesis or prog ression of esophageal cancer are poorly understood. We examined accumulatio n of p53 protein in esophageal squamous cell carcinomas including early-sta ge cancers, and its clinicopathological significance. p53 immunoreactivity in the cancer tissues was found in 61 (79.2%) of 77 esophageal squamous cel l carcinomas. Over-expression of p53 protein (diffusely and focally positiv e staining) was seen in 70.1% (54/77). p53 over-expression was detected not only in the cases of in situ or intramucosal carcinomas, but also in invas ive carcinomas. No significant correlations were found between p53 over-exp ression and clinicopathological features such as depth of tumor invasion, l ymph node metastasis or venous/lymphatic invasion. These results suggested that p53 mutations may be closely associated with the early-stage of pre-in vasive esophageal carcinoma, and p53 gene mutations may play an important r ole in the carcinogenesis of human esophageal cancer.