Abstract
The conversion of androstenedione (A) to estrogens, testosterone (T) and 5 α-reduced metabolites was studied in different phases of cell growth in 4 lines of cultured human breast carcinoma cells. Aromatase activity was 10-fold greater in MD and DM than in MCF 7 cells and was undetectable in ZR 75 cells. Estrogen formation in MD and DM lines increased during the phase of exponential growth and decreased to 20% of maximum during confluence. 5α-Reductase activity was determined by the formation of 5α-androstane-3,17-dione (5α-A-dione) and androsterone (AND), and was 5-fold greater in ZR 75 cells than MD cells and 2-fold greater than in MCF 7 cells. This activity was relatively constant during exponential growth and decreased during confluence. T accumulation was inversely related to 5α-reductase activity. The MCF 7 and ZR 75 cells which contain estrogen receptors had the highest levels of 5α-reductase activity while the MD line which lacks estrogen receptors had the lowest 5α-reductase activity. The assessment of aromatase and 5α-reductase activity in addition to estrogen and progesterone receptors may be helpful in predicting hormone sensitivity in human breast tumours.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
