Human stem cells could provide vaccine against bowel cancer

In collaboration with the Press Association

Human stem cells could one day form the basis of a vaccine against bowel cancer by tricking the immune system into mounting an anti-cancer response, US and Chinese scientists have suggested.

The researchers, some of whom were based at the University of Connecticut Stem Cell Institute, noted that previous animal research has suggested it may be possible to generate an anti-tumour response by immunising with embryonic materials.

However, their study, which is published in the journal Stem Cells, is the first to suggest that human stem cells could be used in a vaccine against bowel cancer.The researchers tested the technique on laboratory mice, which were given human embryonic stem cells.

They found that this brought about a 'consistent' immune response when they were subsequently given bowel cancer cells.

Mice which had been given the stem cells had slower growing tumours, indicating that injections of human embryonic stem cells had 'taught' their immune system to attack the cancer.

However, the studies revealed that the stem cells must be natural embryonic cells - artificially induced pluripotent stem (iPSC) cells did not have the same effect.

Immunology expert Dr Zihai Li commented: "This finding potentially opens up a new paradigm for cancer vaccine research.

"Cancer and stem cells share many molecular and biological features. By immunising the host with stem cells, we are able to 'fool' the immune system to believe that cancer cells are present and thus to initiate a tumour-combating immune programme."

Fellow researcher Dr Bei Liu added: "Although we have only tested the protection against colon cancer, we believe that stem cells might be useful for generating an immune response against a broad spectrum of cancers, thus serving as a universal cancer vaccine."

Dr Julie Sharp, Cancer Research UK's senior science information manager, said: "This is an interesting study in mice and suggests a new approach to cancer vaccines. But this work is still at an early stage.

"Scientists don't yet know if it could be used as an effective and safe cancer treatment. It will be some time before thorough testing in clinical trials can prove if this approach could be used to treat cancer patients."

References

Li, Y., Zeng, H., Xu, R., Liu, B., & Li, Z. (2009). Vaccination with Human Pluripotent Stem Cells Generates a Broad Spectrum of Immunological and Clinical Response against Colon Cancer Stem Cells DOI: 10.1002/stem.234