It’s come time to lie about science again – this time about the reality of embryonic stem cell pluripotency – and some of the old lies are coming back out of the storage shed. For instance, Andrew Breitbart on Real Time last night, and in a video from (liar for Jesus) Tony Perkins of the Family Research Council, I’ve heard about how adult stem cells have cured or treated 72 diseases. Oh and embryonic stem cells, they’ve cured none. It’s been a while since we’ve seen this adult stem cell nonsense.
I had to jog my memory for a minute, I knew this was a lie, but it had been so long since I heard it, that I really had to think about where I had heard it from. Oh yeah, this nonsense list that was famously cribbed by Ann Coulter from a right-to-life group.
To understand the problem with this list and why these citations don’t say what they think they say, we have to learn a little bit about adult stem cells and a big scary word – transdifferentiation. Adult stem cells, which exist in many tissues throughout your body, have specific jobs to perform for the human body to continue to function. Hematopoietic (blood) stem cells make all the red blood cells, white blood cells, and platelets you need to as they are continuously lost or degenerating as part of their natural life span. Stem cells in your gut continuously replace the lining of your intestines as it wears down from the harsh process of breaking down food. There are stem cells that have been isolated from most tissues that function as a repair and maintenance pool of cells to keep our organs functional. Not all organs have a ready pool of stem cells, and most stem cell populations, with the notable exception of blood stem cells, are hard to harvest without risking injury to the host.
However, while these cells are great at doing their job, the issue with adult stem cell research is, can they do another stem cell’s job? That is, instead of making just blood, could a hematopoietic stem cell make, say, an insulin secreting pancreatic cell? The answer, despite some initial promising results around 2001, is no. While hematopoietic stem cells may be able to make some other mesenchyme or connective tissue cells from the mesodermal germ layer, it doesn’t appear that we can make such adult stem cells transdifferentiate – or make a type of cell from another embryonic germ layer. This ability is what is meant by totipotency. The ability to differentiate not just into one of the three major tissue types (mesoderm, ectoderm and endoderm), but all three of them.
So, what is up with this list then? They have 72 treatments using adult stem cells!
No they don’t. This is a lie. They really only are describing one treatment in most of these list items. That is, hematopoietic stem cell replacement of marrow being used in the course of treatment of many diseases. The hematopoietic stem cells are not treating these illnesses, they’re letting us use chemo, or irradiation, and then replenishing the patient’s blood supply. In other words, they’re doing what a good blood stem cell does, replace blood. They’re not treating the disease at all.
Let’s take a look at some of these references.
Here are the first twelve on the list:
BRAIN TUMORS–medulloblastoma and glioma
Dunkel, IJ; “High-dose chemotherapy with autologous stem cell rescue for malignant brain tumors”;
Cancer Invest. 18, 492-493; 2000.
Right off the top of the list (you think they’d use a better one to start) we have an example of hematopoietic stem cells being used to replace bone marrow, not treat the disease! The stem cells are not doing anything for brain cancer, they’re simply allowing high dose chemo-which injures the marrow- to be administered with subsequent auto-transplant of the patient’s own blood stem cells to recover their blood and immune system
Abrey, LE et al.; “High dose chemotherapy with autologous stem cell rescue in adults with malignant primary brain tumors”; J. Neurooncol. 44, 147-153; Sept., 1999
See above. Blood stem cells being used as part of chemotherapy to replace blood, not treat the disease.
Finlay, JL; “The role of high-dose chemotherapy and stem cell rescue in the treatment of malignant brain
tumors: a reappraisal”; Pediatr. Transplant 3 Suppl. 1, 87-95; 1999
See above. Blood stem cells being used as part of chemotherapy to replace blood, not treat the disease.
RETINOBLASTOMA
Hertzberg H et al.; “Recurrent disseminated retinoblastoma in a 7-year-old girl treated successfully by high-dose chemotherapy and CD34-selected autologous peripheral blood stem cell transplantation“; Bone Marrow Transplant 27(6), 653-655; March 2001
See above. Blood stem cells being used as part of chemotherapy to replace blood, not treat the disease.
Dunkel IJ et al.; “Successful treatment of metastatic retinoblastoma”; Cancer 89, 2117-2121; Nov 15 2000
See above. Blood stem cells being used as part of chemotherapy to replace blood, not treat the disease.
OVARIAN CANCER
Stiff PJ et al.; “High-dose chemotherapy and autologous stem-cell transplantation for ovarian cancer: An autologous blood and marrow transplant registry report”; Ann. Intern. Med. 133, 504-515; Oct. 3, 2000
See above. Blood stem cells being used as part of chemotherapy to replace blood, not treat the disease.
Schilder, RJ and Shea, TC; “Multiple cycles of high-dose chemotherapy for ovarian cancer”; Semin. Oncol. 25, 349-355; June 1998
See above. Blood stem cells being used as part of chemotherapy to replace blood, not treat the disease.
MERKEL CELL CARCINOMA
Waldmann V et al.; “Transient complete remission of metastasized merkel cell carcinoma by high-dose polychemotherapy and autologous peripheral blood stem cell transplantation“; Br. J. Dermatol. 143,
837-839; Oct 2000
See above. Blood stem cells being used as part of chemotherapy to replace blood, not treat the disease.
TESTICULAR CANCER
Bhatia S et al.; “High-dose chemotherapy as initial salvage chemotherapy in patients with relapsed testicular cancer”; J. Clin. Oncol. 18, 3346-3351; Oct. 19, 2000
See above. Blood stem cells being used as part of chemotherapy to replace blood, not treat the disease.
LYMPHOMA
Tabata M et al.; “Peripheral blood stem cell transplantation in patients over 65 years old with malignant lymphoma–possibility of early completion of chemotherapy and improvement of performance status”; Intern Med 40, 471-474; June 2001
See above. Blood stem cells being used as part of chemotherapy to replace blood, not treat the disease.
Josting, A; “Treatment of Primary Progressive Hodgkin’s and Aggressive Non-Hodgkin’s Lymphoma: Is There a Chance for Cure?”; J Clin Oncol 18, 332-339; 2000
See above. Blood stem cells being used as part of chemotherapy to replace blood, not treat the disease.
Koizumi M et al.; “Successful treatment of intravascular malignant lymphomatosis with high-dose chemotherapy and autologous peripheral blood stem cell transplantation”; Bone Marrow Transplant 27, 1101-1103; May 2001
See above. Blood stem cells being used as part of chemotherapy to replace blood, not treat the disease.
This list is a lie. They are describing one treatment with adult stem cells in these twelve instances, and the rest of the list is more or less the same thing. Yes, it is true, since the 1950s we’ve been using adult stem cell therapy. We’ve been doing bone marrow transplantation (which is really just stem cell transplant – nowadays we just mobilize the marrow stem cells into the peripheral blood and harvest them there). However, it is dishonest to use every instance that bone marrow is transplanted as part of treatment of a disease to say that “adult stem cells treat 72 diseases”. No! Chemo is treating 72 diseases. Bone marrow transplant is treating one disease in all twelve of these instances – post-chemotherapy bone marrow suppression. Adult stem cells are doing their one thing – differentiating into their destined progeny. They are not transdifferentiating into many different cell types, with the exception of cord blood which does show some promise in this respect.
Further I’m familiar with many of these papers, and many of these papers do not represent treatments that are routinely used. Don’t get me wrong, they’re wonderful papers, but many of these treatments have not panned out, like injecting hematopoietic stem cells or other adult stem cells into the heart. This not being widely implemented because we haven’t been able to show a great benefit, and the little benefit that has been observed has not been from transdifferentiation of the cells into cardiac cells (some cells may fuse to existing myocytes and the injected cells are usually only transiently present), but some effect of cytokines the cells release in the infarct area. Some of the treatments tried on this list are more risky or harmful than the disease, as bone marrow transplant is not without significant risks and potential for harm to the recipient. They are therapies of last resort. Some of them I know have been totally abandoned.
So, of the few on the list that aren’t just repetition of bone marrow transplant, you have experimental therapies which are just that, experimental. None that I see are actually implemented outside of experimental protocols. To sum up, the true state of the field is that with the exception of hematopoietic stem cell transplant to replace bone marrow, adult stem cells are no farther along in application to human disease than ES cells are – they are in a purely experimental stage.
Embryonic stem cells are so promising because they don’t just make one type of cell or cells from one of the three tissue layers. By definition, they can make every type of cell in the body. For example, here is an embryoid body made of mouse ES cells I filmed in my lab, with a focus of beating cardiac cells.
This is functional cardiac tissue generated from completely undifferentiated, and infinitely expandable cell line. That is the power of ES cells. Not just one stem cell job but all of them.
Now, I agree with some of these jokers that they may have one point to argue for their position. As I’ve said as well, iPSC will likely supplant embryonic stem cell therapy as it is a very promising technology that is less difficult, less expensive, and solves the immune rejection problem. However, it’s still a technology in its infancy. We don’t know if iPSC are truly ES cell like, or will be in every instance. We don’t know yet if we can make them without oncogenic transformation. We don’t know if they’ll serve the same way ES cells will for basic science research study because of the possibility of fundamental differences in genetic or epigenetic regulation of the cells.
We just don’t know. So, while iPSC have promise, and I believe will probably, probably, replace ES cells in the long run, it’s simply too early to tell for sure. We should pursue all avenues, and that includes ES cells, especially considering the objection is based on religious dogma about ensoulment, rather than a legitimate ethical concern.
But I’m still left disgusted with these people. Why is it not enough to argue this stuff on the merits? Why do they have to lie, and lie, and lie, about science? Why isn’t the truth part of their moral code, in addition to preserving life?