3 June 2016
Scientists reported a new cancer vaccine which triggers the body’s immune system to attack a tumour as if it is a virus.
Claiming to be the latest advance in immunotherapy, the treatment involves intravenously injecting tiny nanoparticles of fat joined to genetic components of tumour cells (RNA) in order to mimic a viral infection.
Previous attempts to develop vaccines against tumours have been unsuccessful, as cancer cells are similar to normal cells and therefore do not stimulate a strong enough immune response.
Now scientists claim to have engineered immune cells which are able to spot cancer. Following experiments in mice, where the vaccine triggered a strong immune response, low doses of the new RNA vaccine were given to three patients with advanced skin cancer. The study demonstrated that the treatment was safe and all three patients developed an immune response, however there was no evidence that their cancers went away as a result.
The RNA nanoparticles target dendritic cells, which translate RNA from the nanoparticles to produce tumour antigens, a protein attacked by the immune system. These tumour antigens prime T cells to attack cancer. According to the researchers, any tumour antigen can be encoded by RNA the new vaccine approach could be universal.
Professor Alan Melcher, of the Institute of Cancer Research told the Science Media Centre: “Although this research is very interesting, it is still some way away from being of proven benefit to patients…there is uncertainty around whether the therapeutic benefit seen in the mice by targeting a small number of antigens will also apply to humans, and the practical challenge of manufacturing nanoparticles for widespread clinical application.”
Dr Helen Rippon, Chief Executive of Worldwide Cancer Research said: “More research is needed in a larger number of people with different cancer types and over longer periods of time before we could say we have discovered a ‘universal cancer vaccine.’ But this research is a very positive step forwards towards this global goal.”