Scientists find key protein involved in prostate stem cell maintenance

A protein that regulates prostate stem cell self-renewal and maintenance has been identified by US researchers. The so-called Bmi-1 protein also plays a role in the transformation of healthy prostate cells into cancerous ones.

The findings suggest that stopping Bmi-1 from being made protects the cells against damage that can lead to the disease. This raises hope in finding treatments for the 35,000 men diagnosed with prostate cancer each year in the UK.

Co-author of the paper, Dr Owen Witte, director of the Broad Stem Cell Research Centre at University of California, Los Angeles, said: 'We conclude by these results that Bmi-1 is a crucial regulator of self-renewal in adult prostate cells and plays important roles in prostate cancer initiation and progression'.

'It was encouraging to see that inhibiting this protein slows the growth of even a very aggressive prostate cancer because that could give us new ways to attack this disease,' he added.

Prostate cancer is the most common cancer among British men and claims more than 10,000 lives a year. Previous research had showed that Bmi-1 was found in high levels in prostate cancer, particularly in hard-to-treat, fast-growing tumours. Normally the body uses the protein to generate prostate cells in place of the damaged ones. However up until now, the protein's role in prostate stem cell maintenance and cancer was not clear.

Dr Helen Rippon from the Prostate Cancer Charity, explains: 'Only by understanding exactly how prostate cancer is triggered and fuelled can we hope to one day control it. We await the results of future trials into Bmi-1 with interest'.

The study was published in the journal Cell Stem Cell.