Sunday, July 29, 2012
Stem cell therapy: Have we discovered the magic bullet?
There has been a lot of hoopla generated by the public regarding stem cell therapy. It’s been touted to be the smoking gun for almost every disease – from stroke to diabetes, to even it’s claim as we have found the “fountain of youth”.
Many clinics offer stem cell treatments and make claims that are not supported by the science of medicine. The International Society for Stem Cell Research (ISSRCR) has come out with an eight-page brochure (updated in 2011) on common problems myths and fallacies that is a MUST read for the general public who want to know more information about stem cell therapy.
This article provides an overview of what stem cell treatment is all about.
First and foremost are the types of stem cells. There are many types of stem cells that come from various places in the body (or formed at different stages in life). Embryonic stem cells form during the earliest stage of development while there are “adult” or tissue-specific stem cells that appear during fetal development and remain in our bodies forever. It should be remembered that our bodies use different types of tissue-specific stem cells for a specific purpose. The most common example is hematopoietic stem cells in the bone marrow. These are used to regenerate blood and hence are also called blood-forming stem cells. In short, because of tissue-specificity, a certain tissue can only regenerate the same tissue in return. “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!”
Based on the above mechanism of stem cell action, it is unlikely that a single type of stem cell treatment can treat a multitude of diseases like Diabetes and Parkinson’s or Alzheimer’s. The bottom line is that the cell type used as treatment is specific and appropriate to the disease.
Embryonic stem cells are being investigated for a wider range of human diseases. Aside from the current ethical dilemma surrounding embryonic cell stem cell, there are drawbacks in embryonic stem cell treatment because they have bee found to cause tumors and are unlikely to become the cells needed to regenerate a tissue on their own. They will need to get “coaxed” to become a specialized cell, which is currently difficult to do. “A MAJOR WARNING SIGN THAT A CLINIC MAY NOT BE CREDIBLE IS WHEN TREATMENTS ARE OFFERED FOR A WIDE VARIETY OF CONDITIONS BUT RELY ON A SINGLE CELL TYPE”.
Because of the ethical issues surrounding stem cell therapy, the number of well- conducted clinical trials is far from the desired number in order to arrive at a highly recommendable conclusion. The best defined so far are blood, bone, skin and corneal stem cell transplantation. These have been generally accepted as safe and effective in medicine.
“Just because people say stem cells helped them doesn’t mean they did.” The ISSCRC points out that there are three main reasons why a person might feel better that are related to the actual stem cell treatment – placebo effect, accompanying treatments, and natural fluctuations of the disease or conditions. These factors make testing under a non-controlled set-up difficult. It’s like looking at herbal or complementary alternative medicine where you depend on testimonials without the science of clinical trials. Unless there are randomized control studies large enough to make justifiable conclusions, “BE WARY OF CLINICS THAT MEASURE OR ADVERTISE THEIR RESULTS THROUGH PATIENT TESTIMONIALS.”
Science is a long and tedious process. There is no such thing as a medicine that was discovered as a miracle drug overnight. Some medicines may look promising from the get go during pre-clinical studies (in culture cells or animals) but eventually fail in humans. It is estimated that 1 out of 200 molecules that come of research end up in the clinical trial stage. And when a drug is tested in humans, safety is the most important or critical issue. Efficacy of treatment takes a backseat as we weigh benefits to risk of treatments offered.
Stem cells are not magic bullets. They need to get “instructed to behave in specific ways”. BMT or bone marrow transplant is successful because the cells do exactly what they were designed to do – make more blood. The greatest impediment to the development of a successful stem cell therapy is to get the cells to behave the way we want them to. It’s also important to remember that once these cells get transplanted into our body, they need to be in concert (integrate and function) with our body’s other cells as well. At this point, we are still learning how to direct stem cells to become the right cell type, to grow only as much as we need them to, and the best ways to transplant them “BE WARY OF CLAIMS THAT STEM CELLS WILL SOMEHOW JUST KNOW WHERE TO GO AND WHAT TO DO TO TREAT A SPECIFIC CONDITION.”
Like medicines, each medical procedure has a risk. “While your are unlikely to have an immune response to your own cells, the procedures used to acquire, grow and deliver them are risky. Contamination from other bacteria, virus or fungi can occur and can cause a deadly disease, which may be more difficult to treat. It can also cause a reaction to your own cells resulting in an immunologic reaction that can be deadly to the patient.
It is understandable that people feel they have nothing to lose with stem cell therapy because the diseases that stem cell therapy purports to cure are usually considered incurable by other means. Remember, “there are very real risks of developing complications, both immediate and long-term, while the chance of experiencing a benefit is likely very low. “ The bottom line is that “there is something to lose by trying an unproven treatment”.
“Experimental treatment offered for sale is not the same as a clinical trial”. This is the difficult part of explaining to a skeptical public who believe in magic bullets on the differences between experimental treatments and clinical trials. All clinical trials are FREE and the investigating pharmaceutical company shoulders the whole treatment and adverse events that occur during the treatment. An experimental treatment for sale is bogus. “BEWARE OF EXPENSIVE TREATMENTS THAT HAVE NOT PASSED SUCCESSFULLY THROUGH CLINICAL TRIALS”. Responsible medicine requires responsible clinical trial development phases because they allow us to learn if the treatment is SAFE and effective.
With that said, stem cell science is extremely promising. Great advances in treating certain conditions especially of the hematologic system have provided a large avenue for diseases once untreatable. Many scientists are currently studying ways to harness stem cells to diagnose and treat various diseases and conditions. In February 2010, the British company ReNeuron had been approved to do phase 1 studies of a neural stem cell for the treatment of stroke. The US FDA has also approved the first embryonic stem cell-based treatment for acute spinal cord injury in the phase 1 of clinical trials. It will still be quite some time before we probably will see stem cell as basic armamentarium in the treatment of various diseases.
There is a silver lining that will make stem cell therapy a promising treatment alternative in the future. In the meantime, the public needs to understand the science behind stem cell therapy so that scrupulous individuals and clinics that offer it as the “fountain of youth” or the magic bullet to disease treatment do not deceive them.
The most unethical part of medicine is to pan out a treatment at the expense of selling false hope to patients who are desperate to find a cure. The Hippocratic Oath of “First do no harm” should be the dictum at all times.
For more information, log on to www.isscr.org/public/ISSCR08_PubEdBroch.pdf to download the eight-page brochure on Stem Cell Facts
This article was originally written for eMagazine in My Virtual Healthcare Solutions, Inc. at www.myvhs.com.ph.
Posted by Kid at heart at 8:19 PM