Drugs already used to fight breast cancer could be used to combat prostate cancer, noted a researcher from Laval University.
Traditionally, said Professor Étienne Audet-Walsh, prostate cancer is studied in relation to androgen signaling, which are traditionally male hormones.
“But we wanted to see if estrogen signaling was also important in the context of prostate cancer,” added Professor Audet-Walsh, from the department of molecular medicine at the Faculty of Medicine of the Quebec university.
Professor Audet-Walsh and his colleagues therefore studied 280 prostate tumors stored in biobanks at Laval University. They found that half of them had estrogen receptors.
The researchers then discovered, by analyzing the patients’ medical records, that the abundance of these receptors was linked to the risk of cancer recurrence, its progression, the formation of metastases and the survival of patients.
Laboratory studies then reinforced this lead, demonstrating that estrogens, when they bind to receptors, stimulate cellular mechanisms linked to the metabolism and growth of prostate cancer cells.
“Estrogen signaling will in fact promote the aberrant growth or proliferation of tumor cells, in particular by allowing them to have a more active metabolism,” explained Professor Audet-Walsh.
Conversely, it was explained, drugs that block estrogen receptors reduce the proliferation and growth of prostate tumors.
In the vast majority of men who develop prostate cancer, the disease progresses in response to androgens, which explains why treatments that target these hormones are among the interventions regularly used to treat this cancer.
However, the effectiveness of these treatments tends to fade over time, hence the need to find new weapons.
“The results that we have had in preclinical models are that when we use anti-estrogens to block this estrogen signaling, it makes it possible to slow down the proliferation of our different preclinical models, which in fact suggests that the “Patients who test positive for estrogen receptors could benefit from these therapies,” explained Professor Audet-Walsh.
The discovery is all the more promising since these anti-estrogen molecules are already well known and used in women facing breast cancer. It could therefore be relatively simple to transfer them to men to fight prostate cancer.
“If our work results in positive clinical studies, it will make it possible to develop a completely new approach to targeting prostate cancer by targeting estrogen signaling, which would represent a major advance for patients,” concluded Professor Audet. -Walsh.
The number of new cases of prostate cancer detected each year reaches approximately 7,000 in Quebec and 1.4 million worldwide.
The findings of this study were published by The Journal of Clinical Investigation.