Universal cancer vaccine 'a step closer'

A universal "cancer vaccine" that can stimulate the body's immune defences to attack a broad range of potentially fatal tumours has taken an impportant step forward in research published today.

A universal "cancer vaccine" that can stimulate the body's immune defences to attack a broad range of potentially fatal tumours has taken an impportant step forward in research published today.

The vaccine has been made to inhibit telomerase, a naturally occurring enzyme in the body that allows cancer cells to divide uncontrollably. Without telomerase, cancer cells die. Experimental vaccines against cancers are not new but making one specifically directed against telomerase is novel.

Scientists from Geron, a biotechnology company based in California, and Duke University in North Carolina, saypreliminary studies have shown that the vaccine is potentially capable of working against many types of cancers.

Professor Eli Gilboa, the head of the team at Duke University, said the vaccine slowed tumour growth in cancers of the skin, bladder and breast - a range of tumours that no other single cancer vaccine has been able to inhibit.

"The thinking has been that every cancer is different, that each cancer has its own specific set of antigens [proteins which vaccines target] that must be used for a vaccine," he said. "We're looking for a universal antigen."

Results of experiments showed that immune cells stimulated by the vaccine were able to inhibit and kill cancer cells, although not as effectively as experimental vaccines that attack cancer-cell proteins. Professor Gilboa believes it may be possible to engineer a vaccine combining the two approaches.

Professor Nick Lemoine, of the Imperial Cancer Research Fund, said a universal vaccine was unlikely to be developed because there were so many different types of cancer, and attacking telomerase-positive cells could be damaging because the enzyme was present in non-cancerous tissue.