London, July 16: Diabetes drug metformin, which costs as little as 2pence a tablet, could offer a major breakthrough in the treatment of prostate cancer.
Researchers have found that the medicine causes tumours to shrink by slowing the rate at which cancerous cells grow.
If the results are confirmed in bigger trials, it raises the possibility that men could be given the cheap, readily available drug as soon as they are diagnosed, the Daily Mail reported.
Metformin is widely used on the NHS to treat patients with type 2 diabetes.
But recent studies highlighting the drug’s effects against a variety of tumours have generated considerable excitement among cancer researchers looking for powerful new treatments.
Last year, scientists discovered it could slash the risk of ovarian cancer by around 40 per cent.
And Cancer Research UK is currently funding a major five-year study, involving early 5,000 British women with breast cancer, to see if the drug will stop the disease returning and boost survival rates.
Other research teams around the world are investigating metformin’s powers against skin, lung and pancreatic cancer, with promising early results.
In the latest study, doctors at the Princess Margaret Hospital in Toronto, Canada, tested the drug on 22 men after they noticed that it stunted prostate cancer cell growth in laboratory experiments.
All of the men had been diagnosed with tumours and were due to undergo surgery to have their prostates removed.
For six weeks before their operation, each one took 500mg of metformin three times a day, during which time researchers measured the rate at which the tumour cells multiplied.
The results, presented at the recent American Association for Cancer Research annual meeting in Chicago, showed malignant cells grew at a significantly slower rate once the men were put on the drug, suggesting metformin might be able to keep tumours under control.
The findings support a 2009 study, which found that men taking metformin every day to control their diabetes were up to 44 per cent less likely to develop prostate cancer.
“We compared what the prostate cancer looked like when it was first diagnosed to what it looked like when it was removed. And although these are preliminary results, it appeared to reduce the growth rate of prostate cancer in a proportion of men,” said Dr Anthony Joshua, a cancer specialist who carried out the latest study.
Metformin works by reducing the amount of glucose produced by the liver and helping cells mop up sugar that is circulating in the bloodstream, preventing damage from excessive blood sugar levels.
Eleanor Barrie, Cancer Research UK’s senior science information officer, noted: “Larger trials will tell us more in the next few years.” (ANI)