Researches On The Risk Factors Of Esophageal Carcinoma In Anxi Of Fujian Province, A High Accident Area In China

ObjectiveTo explore the risk factors of esophageal cancer in Anxi of Fujian Province, a high-accident area for esophageal cancer in China, so as to provide evidences for making the integrated preventive measures for esophageal cancer in the high accident place.MethodsUsing case-control study, we investigated 237 pairs about their environmental exposures and disease history of the family, and analyzed the risk factors of esophageal cancer. Meanwhile, I immunohistochemically examined p53, p!6 and CyclinDl protein expressions in 47 patients and 50 controls to analyze the association between those protein expressions and esophageal cancer. The multivariate analysis methods were used to assess the roles of environmental factors, inheritance and genes expression in the progress of esophageal cancer.Results(1) By fitting condition logistic regression model, it has showed that the risk factors of esohphageal cancer included over consumption of salt,introversion, smoking, family history of esophageal cancer and often intaking fried food, potato and pickled vegetables in the last 20 years prior to the diagnosis of esophageal cancer, and the protective factors of esophageal cancer were tea drinking, pure water, fruit and bean products.(2) Genetic epidemiology study showed that esophageal cancer possessed the character of familial aggregation in Anxi. According to Falconer' s threshold model of polygene liability, the heritability of patients' first grade blood was 46.5±6.7%. Both of the results of Segregation analysis and Penrose' method analysis showed that the mode of inheritance of esophageal cancer in a moderately high-incidence area of Fujian province coincided with a mode of polygenetic inheritance.(3) The result of immunohistochemistry showed that the alteration rates of the p53 protein, p16 protein and CyclinDl protein were significantly higher in squamous-cell carcinoma of the oesophagus than in normal esophagus.(4) Gene, environmental exposure and inheritance comprehensive analysis showed that the risk factors of esohphageal cancer were often intaking potato, smoking, family history of esophageal cancer, overexpression of p53 protein and absent expression of p16 protein, and the protective factors of esohphageal cancer were tea drinking and bean products.(5)The analysis of gene-environment interactions showed that exposure more than one risk factors can not only increase the risk of esophageal cancer, but also decrease the protective effect of tea drinking. The further analysis of the interaction model between gene and environmental exposures, gene and inherence, environmental exposures and inherence showed that the interactions between over expression of p53 and smoking, often intaking potato, or family history of esophageal cancer presented synergism, so did the association between absent expression of p16 protein and smoking, often intaking potato, or family history of esophageal cancer, in contrast, tea drinking canantagonize the effects of over expression of p53 and family history of esophageal cancer, there was no relation between tea drinking and absent expression of p16 protein.ConclusionEnvironmental factors, inheritance and genes play important roles in the progress of esophageal cancer in the high accident area of Fujian province, and their interactions do especially. The high risk population should be of having the characteristics of risk genetype, exposure to more than one risk factors or have genetic background. To prevent esophageal cancer effectively, we should do follows: First, advising the population living in high accident area to change their behavior habits and adjust meal construction. Second, preventing the high risk population from exposing to environmental risk factors, or using environmental protective factors to intervene. Such studies are expected to shed light on the etiology and prevention of esophageal cancers in the high accident area, and more researches are needed to understand the relationship among environmental exposures, inheritanc...