Stem cells taken from aborted embryos are used as treatments for a variety of illnesses including blood disorders, immune deficiencies, auto-immune diseases, cancer and brain injuries. Once heralded as a miracle by the medical community, it was decried as immoral by pro-life supporters and other members of the general public.
Now there is more than just a moral reason why it shouldn’t be done.
Research carried out at the Hebrew University of Jerusalem has found that embryonic cells have a capacity to develop into cancerous cells, so what was once thought of as an ounce of prevention may turn out to be a pound of death.
Embryonic stem cells have not yet developed into tissue or body parts and are the road map for the body, the blueprint of the future child, known as undifferentiated cells. This means they have the ability to grow into any cell at all, including cancerous cells.
Japanese scientists then developed a way of extracting embryonic stem cells from adults by reprogramming mature cells. This meant a sick patient could use his own cells as a treatment and it minimized his chance of rejecting the cells. These reprogrammed cells were called induced pluripotent stem (iPS) cells.
In order to be used as a treatment, the cells must be raised in a culture. During culture it was found that they underwent chromosomal changes, including changes that signified cancer growth.
In healthy cells, each cell has two copies of each chromosome, but in these embryonic cells, three pairs of chromosomes were discovered and the third pair were able to rapidly overpower the other normal pairs, causing cancerous growths.
Researchers examined over 100 embryonic cell lines from around the world and found that there were a large number that displayed the same chromosomal changes, even though these cell lines had previously been considered normal.
“Our findings show that human iPS cells are not stable in culture, as was previously thought, and require reassessment of the chromosomal structure of these cells,” Professor Benvenisty said. “Also, our work shows for the first time the gene expression changes that accompany these chromosomal aberrations found in the culture, paving the way for our beginning to understand the mechanism by which these changes occur.
“The chromosomal changes in these iPS cells require everyone to exercise great care in continuing to work with them, since these changes apparently will influence the differentiation potential and the tumorigenic risk of these cells.”
Cases of cancer have also developed after patients have been injected with standard embryonic cells.
For instance, a 9-year-old boy from Russia developed a brain tumor as a teenager after he received a neural stem cell transplant from fetal brain tissue.
Scientific American magazine published a report warning of the dangers of using stem cells as a treatment:
"A dark side of stem cells-their potential to turn malignant-is at the root of a handful of cancers and may be the cause of many more. Eliminating the disease could depend on tracking down and destroying these elusive killer cells."
More research needs to be done before this type of therapy is given to large numbers of patients as it is clearly experimental, not proven safe and in some cases shown to be dangerous.
Sources:
'Identification and Classification of Chromosomal Aberrations in Human Induced Pluripotent Stem Cells'
Yoav Mayshar, Uri Ben-David, Neta Lavon, Juan-Carlos Biancotti, Benjamin Yakir, Amander T. Clark, Kathrin Plath, William E. Lowry, Nissim Benvenisty
Cell Stem Cell, 8 October 2010, 7(4) pp. 521 - 531
Discover Magazine - http://blogs.discovermagazine.com/80beats/2009/02/18/embryonic-stem-cell-therapy-causes-cancer-in-teenage-boy/
http://www.scientificamerican.com/article.cfm?id=stem-cells-the-real-culpr-2006-07
Joanna is a freelance health writer for The Mother magazine and Suite 101 with a column on infertility, http://infertility.suite101.com/. She is author of the book, 'Breast Milk: A Natural Immunisation,' and co-author of an educational resource on disabled parenting, in addition to running a charity for people damaged by vaccines or medical mistakes.