A study conducted by researchers at the Cleveland Clinic has revealed an unexpected role for male hormones in protecting men from one of the most dangerous types of brain tumors, glioblastoma.
The results showed that lower levels of androgen hormones, especially testosterone, may contribute to accelerating the growth of this tumor rather than limiting it, as was previously thought.
The study relied on preclinical trials, in addition to analyzing data from over 1,300 men with glioblastoma. Researchers found that patients who received testosterone supplements for other health reasons had better survival rates compared to those who did not, with a 38% reduction in their risk of death.
The study, published in the journal Nature, described its findings as potentially opening the door to new treatment strategies for this aggressive type of cancer, which affects men at higher rates than women.
Dr. Anthony Litay said the results were a "positive surprise" and could help in the future to develop more effective treatments for brain cancer.
The researchers focused on understanding the impact of androgens within the complex environment of the brain, a point that has not received sufficient attention in previous studies. It was widely believed that male hormones might promote tumor growth due to the higher incidence rates among men, but the new findings suggest the opposite.
The study's lead researcher, Dr. Justin Lathia, explained that the brain has a highly sensitive protection system that prevents the entry of many cells and factors coming from the rest of the body, including immune cells.
In experiments on mice, researchers discovered that lowering androgen levels disrupted the body's stress response system, known as the hypothalamic-pituitary-adrenal (HPA) axis. This resulted in elevated stress hormones and inflammation in specific brain regions, leading to increased isolation of the brain from the immune system.
This change created an immunosuppressive environment within the brain, reducing the ability of immune cells to reach and attack the tumor, causing the tumors to continue growing more rapidly. The researchers also noted that testosterone did not have the same effect in female mice.
Although the study does not definitively prove that testosterone protects against brain cancer, the researchers believe the results warrant further investigation through clinical trials on humans.
The research team plans to find out if some androgen-lowering therapies, currently used in other types of cancer, might be harmful to glioblastoma patients.
Lathia said one of the next steps will be to study the effect of "androgen deprivation" on patients with this tumor, to see if this treatment approach could have adverse effects in brain cancer.
