Steroidal Anticancer Agents: An Overview of Estradiol-related Compounds

Research of steroidal compounds as anticancer agents started almost 50 years ago. During the past decades, several innovative new steroids, like cyproterone, finasteride, estramustin, exemestane and fulvestrant have successfully become a part of routine clinical practice. Meanwhile, a vast amount of new information have accumulated about the functions of the endogenous steroid system (including the characterization of enzymes, receptors, transcription pathways, etc.) and about the role of steroids in carcinogenesis. Therefore, it is regularly required to review the latest published results, focusing on a well-defined part within this research field that has definitely developed into a highly diversified speciality by now. Herein, we make an attempt to summarize the most recent results reported about anticancer agents of estrane backbone, focusing on their mechanisms of action and their structure-activity relationships. Due to the vast number and various accessibilities of scientific publications, neither other reviews nor this one can be considered as absolutely exhaustive. In spite of these restrictive factors, the current review makes a good opportunity to define the recent scientific trends in the field of estradiol-related anticancer agents.