Metabolism of Steroids TumoP by Transplantable Mouse Interstitial Cell

Biotransformation of steroid hormones by a spontaneous interstitial cell tumor originating from a BALB/cJ mouse has been studied in vitro. Tumor tissue grown in a female host converted estrone predominantly to estradiol-17~. The same tissue transformed estradiol-17/~ to estrone to a considerably lesser extent. Incubation of the tumor tissue with androstenedione yielded testosterone as the principal conversion product and several other metabolites with chromatographic characteristics of l lB-hydroxytestosterone, 11~-hydroxyandrostenedione, and 11-ketotestosterone. Interstitial cell tumors grown in male and female hosts transformed progesterone to testosterone, 20a-hydroxypregn-4-en-3-one, androstenedione, and 11-deoxycorticosterone. The tumor tissue in vitro showed the presence of enzyme systems which are commonly found in testis tissue as well as steroid 11~/and 21-hydroxylases which are normally localized in adrenocortical cells. Testis tissue from animals bearing interstitial cell tumor formed in vitro less testosterone from progesterone than testes from normal animals.