London- U.S. researchers have succeeded in developing a new prostate cancer therapy that focuses on “shocking tumors.”
A man with advanced prostate cancer has seen the disease disappear, after doctors from Johns Hopkins University School of Medicine in Baltimore “shocked” his tumors with huge amounts of testosterone.
The treatment also slowed the progress of the disease in the majority of the 46 other patients in a small, ongoing clinical trial.
“The results are unexpected and exciting,” said lead researcher Sam Denmeade from the Johns Hopkins University School of Medicine. “Our goal is to shock the cancer cells by exposing them rapidly to very high followed by very low levels of testosterone in the blood.”
“We are still in the early stages of figuring out how this works and how to incorporate it into the treatment paradigm for prostate cancer,” he added.
The test took 47 men through at least three cycles of exposing the cancer cells to extremely high doses of testosterone followed by a period of low levels of testosterone, which were caused by a drug that stopped the production of testosterone in their testicles. This treatment is currently known as bipolar androgen therapy (BAT).
Doctors used prostate specific antigen (PSA), a blood marker used to track prostate cancer levels in the men, to study the trajectory of the disease as it was treated. Denmeade said that the PSA levels fell for the majority of the 47 men, with one man with no trace of PSAs in his body.
Each year around 47,000 men are diagnosed with prostate cancer in the UK and 11,000 die from the disease.
Dr. Matt Hobbs, deputy director of research at the charity Prostate Cancer UK, said: “Drugs that reduce the levels of testosterone (androgen deprivation therapy) are an effective treatment for thousands of men with advanced prostate cancer.
“However, at some point the cancer evolves and those drugs stop working. This research is intriguing because it offers a hint that – somewhat unexpectedly – for some men whose cancers have reached that ‘hormone-resistant’ stage it may be possible to kill or stop growth of the cancer cells by actually overloading them with testosterone.
“Many exciting new lines of attack against prostate cancer are emerging of which this is one.
“However, this is early stage research and further studies are needed in order to understand exactly how intriguing developments like this work and to test the findings more robustly in large clinical trials.”