You W C, Chang Y S, Yang Z T, Zhang L, Xu G W, Blot W J, Kneller R, Keefer L K, Fraumeni J F
Beijing Institute for Cancer Research, China.
IARC Sci Publ. 1991(105):33-8.
Research over the past several years in an area of Shandong, China, with one of the world's highest rates of gastric cancer, has yielded clues to the environmental determinants of this tumour. Interviews with 564 gastric cancer patients and 1131 population-based controls revealed increased risks associated with consumption of sour pancakes, a fermented staple unique to the area, in samples of which volatile N-nitrosamines have been detected. Lower risks were found among people who had a higher intake of fresh vegetables, including garlic and other Allium vegetables which contain constituents that can inhibit carcinogenesis by N-nitrosamines and other substances in experimental animals. A pilot study involving assays of urine and gastric juice from 60 individuals in a screening programme showed higher levels of N-nitrosoproline and of cis- and trans-N-nitroso-2-methylthiazolidine 4-carboxylic acid among persons with gastric dysplasia than in either normal controls or those with chronic atrophic gastritis. We are trying to characterize the transition and progression of precursor lesions to gastric cancer and to evaluate the role of dietary variables, nutrients, N-nitroso compounds and other factors in particular stages of the carcinogenic process.
在胃癌发病率位居全球前列的中国山东省某地区，过去几年的研究已揭示出这种肿瘤的环境决定因素。对564名胃癌患者和1131名基于人群的对照者进行访谈后发现，食用酸煎饼（该地区特有的一种发酵主食）会增加患病风险，在酸煎饼样本中已检测出挥发性N-亚硝胺。而新鲜蔬菜摄入量较高的人群患病风险较低，这些蔬菜包括大蒜及其他葱属蔬菜，实验动物研究表明，这些蔬菜中的成分可抑制N-亚硝胺及其他物质的致癌作用。一项初步研究对筛查项目中的60个人的尿液和胃液进行了检测，结果显示，胃发育异常者尿液中的N-亚硝基脯氨酸和顺式及反式N-亚硝基-2-甲基噻唑烷-4-羧酸水平高于正常对照者或慢性萎缩性胃炎患者。我们正试图明确癌前病变向胃癌转变和进展的特征，并评估饮食变量、营养素、N-亚硝基化合物及其他因素在致癌过程特定阶段所起的作用。
