Cancer Vaccine From Stem Cells

A new vaccine has been discovered by the researchers from Stanford University using stem cells that have proven effective against breast, lung and skin cancer in mice. Ana Sandoiu wrote an article that was fact-checked by Jasmin Collier. They turned to induced pluripotent stem cells (iPSCs), which are stem cells generated from adult cells.

The Japanese-based scientists showed over a decade ago that adult cells can be genetically reprogrammed to behave in the same way as pluripotent stem cells. They can take any shape or function and can specialize in whatever type of cell the body needs.

The most well-known type of pluripotent stem cell is embryonic stem cells. By immunizing animals with embryonic tissue it caused them to reject tumors. This led scientists to believe the embryonic stem cells can be used as a sort of vaccine against cancer tumors. The number of antigens or foreign agents that elicit an immune response is limited, that the immune system can be exposed to at once.

Dr. Joseph C. Wu of the Institute for Stem Cell Biology and Regenerative Medicine at Stanford University in California and colleagues believe that using iPSCs generated from the patient’s own genetic material has a range of immunogenic advantages. The research was led by Dr. Wu and they set out to test this hypothesis in mice. The results were published in the journal Cell Stem Cell.

The mice’s own cells were used to create the iPSCs, which was later vaccinated in the rodents and targeted several tumor antigens at the same time. The reason for using whole iPSCs is that the vaccine does not have to identify the antigen to target in a specific kind of cancer.

A larger number of tumor antigens found in iPSCs presented to the immune system makes their approach less susceptible to immune evasion by cancer cells. Many of the antigens found on the iPSCs could also be found in cancer cells. When the rodent received the iPSCs shot, their immune system reacted to the iPSCs antigens. Because the antigens in the iPSCs were so similar to the ones in the cancer cells, the rodents became immune to cancer.

Out of 75 treated mice, 70% rejected breast cancer cells and 30% had smaller tumors within 4 weeks of getting the vaccine. The same happened in lung and skin cancer models. The effectiveness of the iPSC vaccine in reactivating the immune system to target cancer was the most surprising. This may have clinical potential to prevent tumor recurrence or target distant metastases.

Dr Fredda Branyon