Unconjugated and glucuronide steroid levels in human breast cyst fluid.

The present report deals with the concentrations of C-21, C-19 and C-18 steroids as well as steroid glucuronides, namely androstane-3 alpha,17 beta-diol glucuronide, androsterone glucuronide, estradiol glucuronide, and estrone glucuronide (E1-G) in breast cyst fluid (BCF). The concentration of the gross breast cystic disease protein 15 (GCDFP-15) was also measured and its value was correlated with concentrations of unconjugated steroids as well as steroid conjugates. The present data indicate that for a large number of unconjugated steroids (namely pregnenolone, progesterone, dehydroepiandrosterone (DHEA), androsterone, androstane-3 alpha,17 beta-diol, estrone and estradiol) there is an important accumulation in BCF. Our data permit us to demonstrate a statistical relationship between the concentrations of DHEA and its metabolites (namely, androstenedione [4-ene-Dione]), thus suggesting an activity of the enzyme 3 beta-hydroxysteroid dehydrogenase-4-ene-5-ene-isomerase in the breast tissue. Further examination of the relationship between the concentrations of 4-ene-Dione and its metabolites, namely testosterone and 5 alpha-reduced steroid metabolites, as well as their glucuronide derivatives, strongly suggests that the metabolism of androgens in the breast tissue occurs mainly via 5 alpha-reductase and glucuronyl transferase activities. The concentration of GCDFP-15 in BCF found in the present investigation was 2745 +/- 234 micrograms/ml and we have shown that a negative relationship exists in the BCF between E1-G and GCDFP-15 levels.