Worthington B S, Syrotuck J A, Ahmed S I
J Nutr. 1978 Sep;108(9):1402-11. doi: 10.1093/jn/108.9.1402.
The present study was designed to evaluate in a syngeneic system the longterm effect of dietary reduction of each of three essential amino acids on carcinogenesis with methylcholanthrene (MCA) and immunity to a transplanted MCA tumor. Inbred mice were provided a standard amino acid diet or a diet deficient in isoleucine, leucine, or phenylalanine-tyrosine. In the carcinogenesis experiment, MCA pellets were implanted in each mouse and weekly records were maintained of body weight, tumor incidence, tumor size, and death rate. Mice in the immunity study were inoculated with syngeneic tumor cells; tumors were excised when the largest tumor in the control group reached 12 mm and each animal then received a second challenge of tumor cells. The available data suggest that (1) restriction of the selected amino acids does not inhibit chemical carcinogenesis with MCA, (2) phenylalanine-tyrosine deficiency may actually enhance chemical carcinogenesis with MCA, and (3) selected essential amino acid deficiencies do not enhance immunity to a transplanted MCA tumor.
本研究旨在同基因系统中评估饮食中三种必需氨基酸各自减少对甲基胆蒽（MCA）致癌作用以及对移植的MCA肿瘤免疫的长期影响。给近交系小鼠提供标准氨基酸饮食或缺乏异亮氨酸、亮氨酸或苯丙氨酸-酪氨酸的饮食。在致癌实验中，给每只小鼠植入MCA丸剂，并每周记录体重、肿瘤发生率、肿瘤大小和死亡率。免疫研究中的小鼠接种同基因肿瘤细胞；当对照组中最大肿瘤达到12毫米时切除肿瘤，然后每只动物接受第二次肿瘤细胞攻击。现有数据表明：（1）所选氨基酸的限制并不抑制MCA的化学致癌作用；（2）苯丙氨酸-酪氨酸缺乏实际上可能增强MCA的化学致癌作用；（3）所选必需氨基酸缺乏不会增强对移植的MCA肿瘤的免疫。
