[Inhibition of the growth of 7,12-dimethylbenz(a)anthracene- and N-nitrosomethylurea-induced mammary gland neoplasms by methionine in rats].

The diets supplemented with 0.5% methionine inhibited the development of mammary adenocarcinomas induced in female rats with 7,12-dimethylbenz(a)anthracene and N-nitrosomethylurea by 3.8 and 2.3 times, respectively. Methionine produced no effect on the incidence of other new-growths. It is suggested that the mechanism by which methionine exerts an antineoplastic effect on mammary carcinomas is a consequence of its hypolipidemic and neurotropic activity.