虽然流病学调查和实验研究证明食物脂肪的类型和数量与结肠癌的发生有密切关系，但尚未从分子水平上完全阐明这些营养因素的调节作用。活化的ras基因编码的转换蛋白与很多人类恶性肿瘤包括结肠癌的病因有关。现在已经证实，ras－p“的转换能力紧密依赖于其在细胞膜表面的正确定 Although epidemiological surveys and experimental studies have demonstrated that the type and amount of food fat are closely related to the occurrence of colon cancer, the regulatory effects of these nutritional factors have not yet been fully elucidated at the molecular level. The transforming protein encoded by the activated ras gene is involved in the etiology of many human malignancies, including colon cancer. It has now been confirmed that the conversion ability of ras-p "is closely dependent on its positive determination at the cell membrane surface.