A new study published in JNeurosci reports that brain-targeted estrogen could reduce side effects associated with breast cancer treatment, according to research led by Agnès Lacreuse from the University of Massachusetts Amherst on June 8. Most breast cancers are worsened by estrogens, so clinicians often prescribe inhibitors like letrozole to block estrogen production. However, many patients do not adhere to this treatment due to negative side effects.
Preclinical studies in rodents have suggested that a drug called 10β,17β-dihydroxyestra-1,4-dien-3-one (DHED), which delivers estrogen only to the brain, may offer a safe and effective way to reduce these side effects. The current research extended this work by testing DHED in aged marmosets—a more advanced animal model than rodents.
The research team found that after treating marmosets with letrozole, subsequent DHED administration increased estrogen levels specifically in the brain and improved both memory and sleep. Additionally, DHED reversed neural changes caused by letrozole. The study also noted different effects of DHED on body temperature regulation between male and female marmosets, indicating a need for further investigation.
Lacreuse said, "Our work suggests that DHED is a promising new hormonal therapy for women with breast cancer and perhaps all menopausal women." The researchers plan future studies to explore how DHED works in the brain and whether adjusting drug doses can address temperature regulation issues related to treatment.
