ANN ARBOR—Patients should be wary of claims made by the operators of stem cell clinics outside the United States who offer unproven and potentially dangerous disease treatments, University of Michigan researcher Sean Morrison said during a segment of the CBS program ’60 Minutes’ that aired Sunday night.

“There are clinics that have been set up in countries with unregulated medical systems that are making claims that are not based on sound scientific and medical evidence,” said Morrison, director of the U-M Center for Stem Cell Biology.

“People who claim that they can cure diseases in the absence of strong scientific evidence are selling snake oil and preying on the hopes of desperate patients,” Morrison said during an interview conducted after the ’60 Minutes’ crew visited his Life Sciences Institute laboratory.

Clinics offering unproven stem cell therapies have arisen in countries such as China, Russia and Mexico. In many cases, there is little or no scientific evidence to support the effectiveness of treatments offered by these clinics, Morrison said. Yet patients are charged large amounts of money for the therapies, based on the promise that bone marrow or umbilical-cord-blood stem cells can cure their disease.

Political opponents of embryonic stem cell research in the United States have claimed that bone marrow or umbilical-cord-blood stem cells can cure more than 70 diseases. Morrison said this claim is inaccurate: To date, bone marrow and umbilical-cord-blood stem cells have only been proven effective for the treatment of blood and immune system diseases.

“If your doctor doesn’t have compelling reason to believe that your disease can be treated effectively with the therapy that is being offered, and if there’s no compelling evidence in the scientific literature that this treatment really is a cure, and if it hasn’t been the basis of sound clinical trials that are open to the light of day and replicated in independent clinics, then there is reason to be skeptical, and you should be very cautious about seeking treatment in those clinics,” Morrison said.

These clinics operate outside of the United States because the U.S. Food and Drug Administration would prevent them from making these claims or offering their therapies in the this country, due to the lack of evidence supporting the safety or efficacy of the therapies, Morrison said.

“The unproven therapies are not sold to patients in the United States because medical care, stem cell research, and human-subjects research are tightly regulated here,” he said.

Clinical trials are being launched now in this country to test whether various types of stem cells can reduce the symptoms of amyotrophic lateral sclerosis, also known as Lou Gehrig’s disease.

Dr. Eva Feldman, director of the U-M’s A. Alfred Taubman Medical Research Institute, will test whether implantation of neural stem cells benefits ALS patients. These studies are promising. But until approved clinical trials like this one have been completed, it will remain unknown whether stem cell transplantation can help these patients, or what kind of stem cell is most effective.

“Stem cell research offers exciting new opportunities to cure disease, and promising research is being done in many countries throughout the world,” Morrison said. “However, years of additional research will be required to determine which diseases can be treated effectively, and how. Until that research is done, and the safety and effectiveness of new therapies are confirmed in clinical trials, there is no basis on which to represent potential new therapies as cures.”