London - Botox jabs could tackle prostate cancer. The toxin, best known for ‘freezing’ wrinkles, is being investigated for its effects on cancer and symptoms of an enlarged prostate.
Botox works by blocking the effect of nerves and researchers believe it could be used to target the nerves supplying tumours. Early research has shown that tumour cells shrivel when the prostate gland is injected with Botox.
In a clinical trial at Texas University, the treatment is being tested on men with localised cancer (where the disease has not spread beyond the prostate gland). Half the gland will be injected with Botox and the other with saline.
The 15 men on the trial are scheduled to have radical prostatectomy - surgery to remove the prostate - at a later date. After the surgery, the cancer cells will be compared to measure the effects of Botox.
Prostate cancer is the most common cancer in men in Britain, with more than 40 000 cases diagnosed each year.
For many men, treatment is not immediately necessary and the cancer is monitored.
Treatments for localised disease include surgery to remove the prostate, radiotherapy and hormone therapy. However, these carry the risk of significant side-effects, including incontinence, erectile dysfunction or impotence.
Early results from three patients on the trial show the side of the tumour injected with Botox had shrivelled significantly; the other side had not.
The researchers say Botox could have similar effects on other types of solid cancers.
Botox jabs have also been shown to work for enlarged prostate, also known as benign prostatic hyperplasia (BPH).
This is an age-related condition where the prostate gradually enlarges and pushes against the urethra, the tube through which urine exits the body. More than half of over-60s have an enlarged prostate, of which up to 50 percent develop bladder control problems as a result.
Research at the University of Pittsburgh found that 75 percent of men injected with Botox had some easing of their symptoms. “Botox has been shown to be safe and effective. One injection, which takes five minutes, can prove effective for a year,” say the researchers.
The jab is thought to work by relaxing the nerves and muscle in the prostate, easing pressure on the urethra to make urinary flow easier.
“For the treatment of enlarged prostate, it will be interesting to see the results,” says Professor Raj Persad, consultant in urology-oncology at North Bristol NHS Trust. ‘For the treatment of men with prostate cancer, it is not so straightforward. It is not known how Botox could exert an effect on cancer cells.
“It may deprive them of nerve elements crucial to their survival, but more research is needed to look at the effectiveness and to compare outcomes with the existing treatments.”