[Effect of retinoids on the development and growth of experimental tumors].

The ability of six retinoids to inhibit cancer growth was tested on mice with Lewis lung carcinoma, PRG and RSM-5 tumors. It was shown that all tumors possess individual sensitivities to retinoids. The most effective substances were: methyl retinoate (all-trans and 13-cis isomers) and a retinoid with a small side chain and an oxidated beta-iononic ring (substance 3). Each of those three retinoids was tested for an ability to prevent methylcholanthrene-induced carcinogenesis in the skin. All-trans methylretinoate had the most pronounced effect; however, it was the most toxic, too.