A new cancer paradox has been discovered. Testosterone which has been known to fuel the growth of prostate cancer, however a new study has discovered that shots can slow the progression of untreatable prostate tumors in some patients.
In the 1940s, it has been known that cutting the levels of testosterone and other male sex hormones can rein in prostate tumors. A common treatment for prostate cancer that has spread to other parts of the body is chemical castration, drugs that cut the body’s production of testosterone and related hormones. Unfortunately, the cancer cells usually adapt to the low hormone levels and resume growing. Researchers have devised new treatments to counter the resistance.
Studies of cancer cells have revealed that cancer cells that prosper when testosterone is scarce often die when exposed to high levels of the hormone Experiments suggest that the extra hormone disrupts DNA duplication and leads to DNA fractures, which can be fatal for a cell. This relationship means that testosterone doses could be beneficial against resistant tumors.
This strategy was tested in 16 men whose prostate cancer had become resistant to chemical castration. Most of their tumors had spread of metastasized. In the study, the men continued to receive the chemical castration therapy but every 28 days were injected with testosterone. Each shot spoke the blood testosterone levels well above the normal, but gradually declined until they were close to the level produced by chemical castration.
In order to gauge the process, the researchers measured the amounts of prostate specific antigen (PSA) in the blood, which is an indicator of prostate cancer growth.
Unfortunately two of the patients left the study in the first round due to side effect. In 7 of the remaining patients, PSA levels rose during the first three rounds, which suggested that they weren’t benefiting from the injections. But the PSA levels in the seven others dipped, which is a sign that their tumors were shrinking.
The rationale is that the cancer cells should not be allowed to get accustomed to low testosterone.