Steroid Hormones, Receptors, and Antagonists

In the thirty-odd years since the first demonstration of estrogen-binding components in reproductive tissues, much has been learned about the molecular details of steroid hormone action. Facts still to be elucidated include the precise mechanism by which interaction with the steroid disrupts the native receptor complex to generate an active transcription factor, just how this activated receptor enhances expression of target genes, and the role of phosphorylation in these events. The concept of receptor-medicated steroid hormone action has provided useful methods for predicting the risk of metastatic recurrence of breast cancers and the response of disseminated disease to endocrine therapy. Application of immunochemical techniques for receptor assay and elucidation of the role of mutant receptors in hormone resistance promise to increase the utility of these diagnostic procedures. A better understanding of the molecular details of steroid hormone antagonism should be helpful in the search for new and more effective agents for the endocrine control of breast cancers.