Many current therapies for breast cancer rely on blocking estrogen receptors from within the cancer cells. This usually prevents disease progression, but in advanced cases, it can lead to drug resistance, leaving doctors with limited alternatives.
There is some hope on the horizon though. Researchers from Case Western Reserve University School of Medicine have recently mapped a previously uncharacterized human estrogen receptor framework that could become the target for a whole new generation of drugs.
“Until now, the structure of the entire estrogen receptor complex was unknown, so it was a challenge to identify novel or functionally important target sites for new drugs”, said in a press release Sichun Yang, Ph.D., senior author of the study. “The structures of individual receptor pieces were known, but how they fit together was a mystery. Our study identified a novel interface that bridges the two major functional units of the receptor”.
This formation links two important sections, one responsible for binding estrogen, the other attached to DNA sectors and controlling genes in response to estrogen levels. “Disruption of the bridge prevents the two major parts of the estrogen receptor complex from communicating, so targeting this interface represents a ‘burning-the-bridge’ strategy for drug discovery.”
The approach combined genetic engineering, proteomics, along with computer modeling and was named iSPOT (integration of Scattering, footPrinting, and dOcking simulation). It will now become an essential tool in testing new (and current) drugs as possible candidates. Since the molecule has structural similarities to other hormone receptors central to ovarian, prostate, and endometrial cancers, the study could have far more reaching implications for drug research.
“Employing our iSPOT technology, we have achieved medium to high-resolution structural models of the estrogen receptor for which no structure was previously available. We hope this will provide a roadmap to study receptor function and test new medications going forward”, said Yang.