Oestrogen Receptor Assay False Positive Analysis?

Abstract

The influence of unlabeled estradiol, DES [diethylstilbestrol] testosterone and R-5020/org 2058 [promegestone] on tritiated estradiol binding was investigated in 162 ER [estrogen receptor] positive cases of patients with primary breast carcinoma. A dextran-coated charcoal as well as a sucrose gradient method was applied. In 122 cases only unlabeled estradiol and DES significantly displaced the binding of labeled estradiol. In the remaining 40 cases, estradiol, DES, as well as testosterone and R-5020/org 2058 were able to displace the high-affinity, saturable binding of tritiated estradiol equally. Possible explanations of this new discovery are discussed.