A COMPARATIVE STUDY OF THE BIOSYNTHESIS OF TESTOSTERONE BY HUMAN TESTES AND A VIRILIZING INTERSTITIAL CELL TUMOUR

Abstract
A comparative in vitro study of an interstitial cell tumour of the testis from a virilized patient and »normal« testes from another male has been made by incubating homogenates of these tissues with radioactive progesterone, 17α-hydroxyprogesterone, testosterone and androst-4-ene-3,17-dione-4-14C. The patient with the testicular tumour was a 14-year old boy whose clinical studies, reported in detail elsewhere, revealed a history of early puberty and laboratory findings of markedly elevated levels of urinary total 17-ketosteroids and pregnanetriol. These urinary values fell to normal following removal of the right testicular tumour, which was interpreted as being a benign interstitial cell tumour on histologic examination. The radioactive metabolites from the testicular tissue of both subjects were separated, purified and identified by partition column chromatography in various systems with authentic standards, formation of derivatives and isotopic dilution analysis. The interstitial cell tumour converted a significant amount of the substrate progesterone into 16α-hydroyprogesterone, besides testosterone and androst-4-ene-3,17-dione; reduction at C20 was also a major reaction when either progesterone or 17α-hydroxyprogesterone was the substrate. On a comparative basis the activity of C17-20 desmolase was about five times more in the tumour as compared to the testicular tissue.