A new website will help people decide which therapies are safe and effective.
By Sandy Kleffman, Contra Costa Times
Leading scientists are warning people to beware of costly, unproven stem cell therapies that have little or no benefit and may be dangerous.
Many with devastating illnesses are mortgaging their homes and borrowing huge sums of money for treatments, which are often performed outside the United States to avoid its safety regulations.
Scientists worry that such therapies could harm people by leading to cancers and other complications.
"It's really the 21st century version of snake oil," said Dr. Arnold Kriegstein, director of the Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research at UC San Francisco.
"As soon as you scratch the surface, you realize that what they're claiming in their literature or what they tell you about, doesn't make sense," he said. "There's this notion that stem cells are in some way magic cells that can treat anything if you just deliver them into the body. That's pseudoscience and make-believe."
Stem cells have captured worldwide attention because of their ability to renew and form new cells. Scientists hope such cells can one day cure a host of deadly diseases by replacing injured and dying cells.
Of particular interest are embryonic stem cells, which can transform into virtually any cell type in the body.
But despite the encouraging signs, scientists are in the early stages of research. To date, only a handful of stem cell treatments have proven safe and effective in clinical trials. These include bone marrow transplants to treat lymphomas and leukemias, or to replace bone marrow destroyed by high doses of chemotherapy during cancer treatments.
Other well accepted therapies involve skin grafts and corneal repair.
But it can be difficult for people to determine which treatments are backed by scientific evidence. Searching the Internet for stem cell therapies will yield more than 200 companies claiming they can cure almost any condition by growing stem cells and injecting them into a patient.
"Once you read those websites and see what they are doing to people, you begin to lose faith in human nature," said Dr. Irving Weissman, director of the Stanford Institute for Stem Cell Biology and Regenerative Medicine, in a written statement. "They will take the last dollars and days of people's lives."
Weissman co-authored a report about the risks published in this week's edition of Cell Stem Cell.
The excitement surrounding stem cell research "has led to unacceptable exploitation of patients' hopes and fears," the report states.
As the immediate past president of the International Society for Stem Cell Research, Weissman convened a task force that oversaw the creation of a website to educate the public about stem cell research and to help people decide whether treatments are effective and safe.
The site, at www.closerlookatstemcells.org, recommends questions to ask before receiving a treatment.
People can also request that the stem cell society investigate a company or clinic. The society will attempt to determine whether a medical ethics committee is involved to protect patients' rights and whether the treatment will be supervised by an official regulatory body such as the U.S. Food and Drug Administration or the European Medicines Agency.
The results will be posted on the website, although it may take four or five months to complete the review.
In addition to protecting the public, stem cell researchers want to avoid having the fraudulent clinics cast a shadow over stem cell research or cause the public to question legitimate breakthroughs.
Scientists still have much to learn about stem cells, including how to ensure that embryonic stem cells transform into a specific cell type.
Worrisome results
One big concern is that stem cells will start producing tumors or cancers during untested treatments, Kriegstein said.
He noted that this happened with a boy in Moscow who developed tumors in his central nervous system as a result of a therapy.
Another worry is that a patient's body could reject the stem cells.
"These cells usually come from one or more donors that are not related to the patient and haven't been in any way matched, so they run the risk of having immune responses that could be significant," Kriegstein said.
It can be risky even to use a patient's own stem cells, the website notes. After the cells are removed from the body, they could become contaminated with bacteria or viruses that cause diseases when they are injected back into the body. If they are grown in a culture, they may lose the normal mechanisms that control growth or may lose the ability to specialize into the cell types the patient needs
Kriegstein said he understands that patients who seek such treatments often have no options. But because of the problems, he said, "I think going to these places is worse than having no treatment at all."
Among the suggested questions for people to ask is the source of the stem cells and how they are isolated and grown.
"Be wary of clinics that offer treatments with stem cells that originate from a part of the body that is different from the part being treated," the website notes. Stem cells from bone marrow regenerate blood, for example, but cannot make brain cells.
Kriegstein urges people to question how stem cells will be delivered to the right part of the body. Stem cells injected into one area may not make it to the area that needs repair, "let alone actually do something once they get there," he said.
Breakthroughs expected
Despite such cautions, Kriegstein and others are convinced the future is bright for stem cell research. Companies and scientists in the Bay Area and elsewhere are striving for scientific breakthroughs and are increasing their knowledge about how such cells work.
The first embryonic stem cell treatment for acute spinal cord injury is under review by the FDA and may soon move into clinical trials.
And in February, the British company ReNeuron announced it had been approved for a clinical trial of a stem cell treatment for strokes.
"We and others around the world are working very hard, as quickly as we can, to test therapies and develop new approaches," Kriegstein said.
"Eventually, I have complete faith that there will be therapies available that will come out of the current research that's going on in stem cell biology, but it will take time," he said. "There are certain disease areas where it may happen sooner than others. But the potential of stem cells is certainly there."
Questions to ask
The International Society for Stem Cell Research has set up a website to help people decide if treatments are effective and safe, at www.closerlookatstemcells.org People can ask the society to review a clinic, although it may take four to five months for a response.
Here are some questions for patients to ask:
- What is the source of the stem cells? How are they isolated and grown?
- How are the cells delivered to the right part of the body?
- How will my immune system be prevented from rejecting these cells?
- What is the scientific evidence that this could work for my disease or condition?
- What are the risks?
- Is a medical ethics committee involved?
- Is there supervision by a regulatory body such as the U.S. Food and Drug Administration or European Medicines Agency?
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