Mecham J O, Rowitch D, Wallace C D, Stern P H, Hoffman R M
Biochem Biophys Res Commun. 1983 Dec 16;117(2):429-34. doi: 10.1016/0006-291x(83)91218-4.
Methionine dependence is the inability of cells to grow when methionine (Met) is replaced by its immediate precursor homocysteine (Hcy) in the culture medium (Met-Hcy+ medium). All normal unestablished cell strains tested to date have been shown to be methionine-independent and thus grow almost as well in Met-Hcy+ medium as they do in Met+-Hcy-medium. Results presented here indicate that out of 23 cell lines derived from diverse types of human tumors, 11 do not grow at all in Met-Hcy+ medium and are absolutely methionine-dependent and 3 grow only slightly in this medium. Many of the tumor cell lines tested have little else in common other than the fact that they are methionine-dependent. The high frequency of occurrence of methionine dependence in diverse types of human tumor cells indicates that methionine dependence may be an important aspect of oncogenic transformation and therapeutically exploitable.
甲硫氨酸依赖性是指当培养基中用甲硫氨酸（Met）的直接前体同型半胱氨酸（Hcy）替代甲硫氨酸时（Met-Hcy+培养基）细胞无法生长的现象。迄今为止测试的所有正常未确立的细胞系均显示为非甲硫氨酸依赖性，因此在Met-Hcy+培养基中的生长情况几乎与在Met+-Hcy-培养基中一样好。此处呈现的结果表明，在源自不同类型人类肿瘤的23个细胞系中，11个在Met-Hcy+培养基中根本无法生长，并且绝对依赖甲硫氨酸，3个在该培养基中仅略有生长。测试的许多肿瘤细胞系除了依赖甲硫氨酸这一事实外几乎没有其他共同之处。不同类型人类肿瘤细胞中甲硫氨酸依赖性的高发生率表明，甲硫氨酸依赖性可能是致癌转化的一个重要方面，并且在治疗上具有可利用性。
