Stem Cell Research: Hope vs. Hype

By Robert F. Onder, M.D., J.D.

Proponents of the so-called “Stem Cell Research and Cures Initiative,” a proposed ballot initiative that would amend the Missouri Constitution to create a right to clone and kill human embryos, often promote the “promise” of embryonic stem cell research. Indeed, the very name of their group promises “lifesaving cures” that will be forthcoming if Missourians pass their initiative. A closer look at the actual state of embryo-destroying research suggests that Missourians are being sold a snake oil, while the ethical alternative of adult stem cell research has shown numerous successes, with many more likely to come in the future.

Embryo Research and Cloning

To date, there have been no human treatments of any disease using embryonic stem cells (ESCs), that is, stem cells derived by killing human embryos. Moreover, there have been no research trials in humans using ESCs. Even some of the widely touted studies in animals are less impressive on closer examination. Some have tried to excuse the lack of progress in ESC research, saying that this is a relatively new field, while adult stem cells (ASCs) have been used for decades. This is misleading. It is true that Thomson and colleagues did not isolate the first human ESC line until 1998, eight years ago. On the other hand, scientists isolated mouse ESCs over twenty years ago.

There are some major problems that plague ESC experiments. First there is an important safety issue: embryonic stem cells introduced into animals have a tendency to form tumors, and these tumors can and have killed animals in the experiments. This has been a problem in animal experiments of ESCs for Parkinson’s disease.

Second, although some assume that ESCs can be grown in culture indefinitely, it has become clear that these lines are genetically unstable. In other words, as the cells grow in the petri dish awaiting experiments, they deteriorate and become unusable.

Third, therapies with ESC lines would not be compatible with the immune system of patients. This is the reason that Initiative proponents insist on the need for research cloning.

Those who promote research cloning (SCNT) say that patients will be treated as follows: A patient has a disease potentially amenable to stem cell therapy. Proponents propose to: 1) use a somatic (body) cell from the patient and enucleated donor eggs to create an embryo clone of the patient; 2) kill the embryo and “harvest” the stem cells from the embryo; 3) make these ESCs become the appropriate tissue; and 4) transplant that tissue back into the patient.

Step 1 has never been accomplished. (Scientists in Korea claimed to have accomplished this, but their work was fraudulent.) We do know, however, that even if step 1 were possible, it would require massive numbers of eggs to treat even one patient by this method, much less the millions that in theory might benefit from stem cell therapies worldwide. For example, to treat the 17 million diabetics in the United States, assuming a generous 20% efficiency in generating embryos by nuclear transfer and a generous 10% efficiency at establishing an ESC line, would require a minimum of 850 million eggs. Assuming 10 eggs can be “harvested” from each donor, 85 million women would have to volunteer to endure the health risks of egg donation to treat American diabetics with this approach, never mind the dozens of other diseases that proponents claim might benefit. Clearly this approach is impractical and raises significant concerns about the exploitation of women.

Step 2, deriving ESC lines from embryos, has been accomplished, but remains far from easy.

Step 3, inducing ESC lines to form the desired tissue, is critical, since ESCs cannot be directly introduced into the patient because of the potential for tumor formation.

Finally, even if cloned ESCs were successfully differentiated into the desired cell type, these cells must be delivered into the appropriate location. This may be difficult or impossible for some diseases. Despite the pro-ESC rhetoric following President Ronald Reagan’s death, Alzheimer’s disease may be an example of such a disease, being a “whole brain” disease. Ronald McKay, of the National Institute of Neurological Disorders and Stroke, admitted that the Alzheimer’s hype was not being aggressively corrected by scientists: “To start with, people need a fairy tale. Maybe it’s unfair, but they need a story line that’s relatively simple to understand.”

Unfortunately, in Missouri, scientists have often been the ones generating the fairy tales.

Adult Stem Cell Research

Many diseases, at least 65 to date, have been treated with adult stem cells (ASCs). Many of these are either cancers or immune deficiencies, in which stem cell transplants are used to repair these defects. Although using ASCs to create other kinds of cells is a much newer field, there have been some striking successes.

Adult stem cells can be obtained from many sources, including bone marrow, blood, liver, nerves, fat, baby teeth, and umbilical cord blood. (The second largest umbilical cord blood bank in the world is at Cardinal Glennon Children’s Hospital in St. Louis.) A clear advantage of ASCs is that ASCs can be obtained from the patient; we all have our own stem cells. Finally, ASCs have not demonstrated the potential to form tumors.

An example of the progress of ASC research is their use for the treatment of heart attacks and heart failure. A recent article in the Annals of Internal Medicine reviews this approach in animal models and in humans. There have been nine published trials of adult stem cells in humans for the treatment of heart disease.

There have been numerous experiments of ASCs in animal models of Parkinson’s disease. While clinical use of ASCs in Parkinson’s disease is clearly in its infancy, one notable success has been reported. In 2001 Levesque, a neurosurgeon at UCLA, treated a patient with his own nerve ASCs, with dramatic improvement. Levesque has FDA approval to conduct a phase II trial.

Initiative proponents have aggressively promoted ESCs as a treatment for spinal cord injury, often citing a rat experiment. ASCs have been used with similar results in mice and in rats. Meanwhile a Portuguese neurologist reports having treated 34 spinal cord injury patients with nasal stem cells with success. Impressive experiments have also been conducted in animal models of diabetes. In one remarkable case a German surgeon used bone marrow ASCs to grow a new jaw for a patient who had been disfigured by cancer surgery!

Implications for Missouri

Proponents of the cloning and embryo research Initiative often pretend that pursuing cloning research will be an economic boon for the state of Missouri. The truth is that ESC and cloning research are far behind the ethical alternative of ASC research. Biotechnology and venture capital companies by and large have avoided embryo and cloning research, while there are numerous private companies pursuing ASC research. What Initiative proponents appear to want is taxpayer funding of their immoral research. Their Initiative would effectively prevent the Missouri Legislature from funding ASC research while restricting funding for cloning research. Missourians should reject the Initiative, both to avoid funding embryo destruction and cloning, but also to encourage more productive adult stem cell research.

Robert F. Onder, M.D., J.D. is an Assistant Professor of Clinical Medicine at Washington University School of Medicine in St. Louis, MO. He is also on the board of directors for Missourians Against Human Cloning and a Republican candidate in the upcoming August 8th primary election for the Missouri House of Representatives District 13 (Lake St. Louis and Wentzville). For more information regarding Missourians Against Human Cloning visit their web site at www.nocloning.com. For information regarding Dr. Onder’s campaign call 636-561-8968 or visit www.bobonder.com.