17 Alpha androstenediol inhibition of breast tumor cell proliferation in estrogen receptor-positive and -negative cell lines

Androstene-3 beta, 17 alpha -diol (17 alpha -AED) inhibits DNA synthesis an d induces apoptosis in several myeloid cancer cell lines. The purpose of th is study was to determine if 17 alpha -AED inhibition of human breast carci noma cell proliferation is dependent on the estrogen or androgen receptor. At concentrations of 12.5 to 50 x 10(-9) M 17 alpha -AED inhibited the prol iferation of ZR75-1, estrogen receptor-positive (ER+) cells, by 54% to 68%. Further, 17 alpha -AED inhibited MDA-MB231, estrogen receptor-negative (ER -) cells, by 33.6% to 56.0%. The inhibitory effect was dose dependent with a minimal effective inhibitory dose at 12.5 x 10-9 M for both cell Lines. B oth 17 beta -AED and estradiol potentiate the inhibitory effect of 17 alpha -AED on ER+ cells at lower doses (3.13 to 6.25 x 10(-9) M) where 17 alpha -AED alone was not inhibitory. The inhibitory action of 17 alpha -AED on hu man mammary carcinomas appears to be independent of either the alpha estrog en or the androgen receptors.