Estetrol proven to have an estrogen antagonistic effect on breast tumour tissue

08-06-2012: Pantarhei Bioscience (PRB  announced the publication of study results of the human fetal estrogen Estetrol (E4) in prevention and suppression of tumor growth in an in vivo mammary tumour model. The findings have been published in the Journal of Hormone Molecular Biology and Clinical Investigation (2012; 9(1): 95-103).

Pantarhei Bioscience is developing E4 for several Women’s Health applications amongst other hormone replacement therapy (HRT), oral contraception, osteoporosis, menstrual migraine and estrogen hormone sensitive cancers.

“Our results in the DMBA rat model for mammary tumour growth show that E4 prevents tumor initiation by DMBA and inhibits the growth of existing DMBA-induced tumors” concluded Monique Visser, PhD., principal scientist of the project and Program Director Estetrol at PRB. “The rat DMBA model is a mammary tumour model and the preferred tool to assess the potential in vivo prophylactic and therapeutic effects of new drugs in breast cancer.”

She added : “One particularly striking finding  was the fact that  E4 was found to have  an estrogen antagonistic effect on breast tumour tissue, especially surprising since other estrogenic hormones used in HRT and in contraception, such as Estradiol (E2) and Ethinylestradiol (EE), are known to have a stimulatory effect on breast cancer growth”.