WEDNESDAY, Oct. 7, 2009 (HealthDay News) -- Human stem cells may provide a means of creating a vaccine against colon cancer and other types of cancers, say American and Chinese scientists.
"Cancer and stem cells share many molecular and biological features. By immunizing 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 tumor-combating immune program," Dr. Zihai Li, of the University of Connecticut Stem Cell Institute, said in a news release.
The research by Li and colleagues is the first to make the connection between human stem cells and colon cancer vaccination.
It has long been believed that immunizing people with embryonic materials may trigger an anti-tumor response by the immune system, but this theory has never advanced beyond animal research. The finding that human stem cells may help immunize against colon cancer is new and unexpected, the study authors pointed out.
In this study, the researchers vaccinated mice with human embryonic stem cells and found that the mice developed a consistent immune response against colon cancer cells. The vaccinated mice showed a dramatic decline in tumor growth, compared with non-vaccinated mice.
While human embryonic stem cells triggered an immune response, artificially induced pluripotent stem cells did not, a finding that challenges the theory that induced pluripotent stem cells are the same as human embryonic stem cells and may replace them at the forefront of stem cell research, Li and colleagues said.
The study was published online Oct. 7 in the journal Stem Cells.
"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," co-author Dr. Bei Liu said in the news release.
The U.S. National Cancer Institute has more about cancer vaccines.