Self-destruct protein discovery for advanced skin cancer

Scientists have designed a “self-destruct” protein which could be used to treat advanced forms of skin cancer. The researchers at St George’s, University of London, found that the small protein – called a p16-related peptide – could kill melanoma skin cancer cells in the lab whilst minimising damage to healthy skin cells.

Melanoma is the fifth most common cancer in the UK

Melanoma skin cancer is the 5th most common cancer in the UK. Every year, there are around 16,700 new cases in the UK.

The study was funded by The British Skin Foundation, Cancer Research UK, and Age UK. The scientists hope that, in the future, the peptide could be used to treat cases of melanoma which have spread around the body (metastatic melanoma).

The peptide is based on an important anti-cancer protein called p16, which works naturally by causing cells to stop dividing permanently if they mutate and start growing abnormally.  In the case of skin pigment cells, they then form a harmless mole instead of melanoma.  However, occasionally one of the cells mutates further and inactivates p16 itself.  It can then escape the growth arrest and divide to become melanoma. 

The p16-related peptide does not just stop melanoma cells dividing, it kills them.  The researchers do not yet know how this useful difference works, and are keen to find out.

In the lab, the scientists gave different concentrations of the peptide to lab-grown human metastatic melanoma cells, normal skin pigment cells and cells called fibroblasts, which form the second, supporting layer of the skin.  The scientists found that the peptide killed almost all melanoma cells along with a few normal pigment cells and didn’t kill any fibroblasts at all.

British Skin Foundation researcher, Professor Dot Bennett of the Neurosciences and Cell Biology Research Institute, City St George’s, University of London explained:

The peptide will need to go through further lab-based tests to see if it can leave more kinds of healthy cells intact, and to reveal the cancer-killing mechanism triggered by the peptide. If these tests are successful, the peptide will need to go through clinical trials to assess how it performs against current treatments for melanoma, or jointly with these.

Chief Executive of Cancer Research UK, Michelle Mitchell adds,

“More people than ever are surviving melanoma skin cancer, but there remains a critical gap in survival between people diagnosed at early stages compared to those diagnosed later.  

“One of the best strategies to address that gap is to find new treatments which attack cancer, whilst minimising harm to healthy cells. p16-related peptide could offer a promising new approach for those patients diagnosed with metastatic disease, where options for treatment are currently more limited.

“Much more research is needed before p16-related peptide can become a new treatment option for melanoma. However, with melanoma skin cancer cases projected to rise by around 50% over the next 20 years, research like this offers new hope that we can beat melanoma for good.”