Interaction between environmental and genetic factors in the development of esophageal cancer

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The purpose of this study is to find out environmental risks for the development of esophageal cancer in Ci-Xian, where is one of the highest incidence area of esophageal cancer in China.Subjects were 404, 352 and 400 inhabitants living in high, medium and low incidence areas of esophageal cancer, as well as 301 esophageal patients. A food intake-frequency survey using the 7-day weighted inventory questionnaire was conducted for these subjects. Occupation, working condition, income per year, family history of diseases, complaints, and demographic features were also included in the questionnaire. The levels of nitrogen compound in selected well water were measured in each three area. Clear-cut differences in the intake of foods were seen among inhabitants living in the three different areas, suggesting that the regional differences in the nutritional style exist. In both males and females, the intakes of potatoes, fruit, vegetables and meat were significantly lower in inhabitants living … More in the high-incidence area than the other inhabitants, much the same as those of cancer patients. The lowered intakes of carotene, vitamin A and C were also seen in populations living in the high-incidence area of esophageal cancer. The polluted well water with nitrogen compounds was significantly related to the high incidence of esophageal cancer. In contrast, tobacco, alcohol consumption, and intake of pickled vegetable and moldy foods did not relate to the different incidence. These results suggest that the lowered intakes of fruit, vegetables, potatoes and meat, and quality of well water may be important risks for 'the development of esophageal cancer in Ci-Xian.Carcinomas of upper digestive tract (squamous-cell carcinoma of the esophagus) from 65 patients residing in Ci-Xian (China) and near-by high-incidence areas were analyzed for mutations in exons 5-8 of the p53 tumor-repressor gene. Mutations were identified by polymerase chain reaction amplification. Of 65 specimens, 40% had mutations mainly in exon 5 and 8. In general, patients without p53 mutations had lowered intake of several kinds of foods. Especially, the intake of meat was significantly lower in patients without p53 mutations than in those with p53 mutations. Less