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The source of this article is the Houston Chronical: http://tinyurl.com/c7pgk

April 30, 2005, 10:36PM

Stem cell studies hopeful but time needed for cures
Overpromising research could jeopardize its future
By DAVID A. SHAYWITZ


LAST week the National Academies released new guidelines for research 
involving human embryonic stem cells, the latest milestone in what has been 
an unusually eventful time for investigators in this field. Last November 
the voters of California approved $3 billion in funding for stem cell 
research, and earlier this month Massachusetts lawmakers approved powerful 
new legislation that defines and defends this exciting new area of science. 
Yet, unless proponents of stem cell research learn to preach patience as 
well as promise, their celebration will be short-lived.

Human embryonic stem cells were first identified less than a decade ago. 
They captured the attention of scientists because of two essential 
properties: They can duplicate themselves in a culture dish, and they can 
go on to form any cell type in the body. The therapeutic potential seems 
both apparent and unlimited: Convert these cells into neurons and treat 
Parkinson's disease, the reasoning goes; turn them into insulin cells and 
cure diabetes.

That's the plan, anyway. In fact, the deliberate conversion of human 
embryonic stem cells into any other type of cell remains a formidable 
scientific challenge. Even growing these stubborn cells is notoriously 
difficult. And even if we could make replacement cells in a culture dish, 
we would still face the daunting task of introducing them into the body.

The real question, however, isn't whether these problems will be solved, 
but when. And here, the unfortunate truth is that science — good science — 
can be maddeningly slow. While stem cell advocates have helped voters 
connect embryonic stem cell research with compelling images of patients who 
might one day benefit from treatment, such therapies are unlikely to emerge 
soon enough to benefit most current proponents — although patients with 
Type 1 diabetes may represent an important exception.

Soon the advocacy groups that have been so instrumental in supporting stem 
cell science will face mounting pressure to demonstrate that they have bet 
on the right technology. From the researchers, tremendous progress will be 
expected, and the science is unlikely to keep pace with the eager expectations.

This scenario has a familiar ring. For years it was not stem cells but gene 
therapy — the idea of fixing a disease by mending broken DNA — that seemed 
to be the ultimate expression of molecular medicine. Cures, we were told, 
lay just around the corner. Unfortunately, success turned out to be much 
harder to achieve in people than to diagram on a chalkboard. The tragic 
death of clinical study volunteer Jesse Gelsinger, and the concurrent 
realization that the promised cures were years away, finally burst the 
bubble. Today a disappointingly small number of hardy investigators remain 
in what was once medicine's most highly anticipated new area of research.

Is this going to be the fate of embryonic stem cell science in five or 10 
years? I hope not, and yet it's also not very difficult to imagine this 
happening. Already newspapers are filled with extravagant claims of 
progress and cures. These reports belie the very slow rate of true 
scientific advancement. Add to this the explicit expectation of rapid 
clinical progress — a key component of California's recently approved stem 
cell initiative, for example — and you have a recipe for trouble. If 
embryonic stem cells are rushed into clinical trials before the solid 
science has been done, the resulting fiasco could easily doom the entire 
future of the field.

How can we avoid this fate? For starters, scientists must do a better job 
of articulating the limitations of our existing knowledge, taking care to 
emphasize not only the ultimate therapeutic potential of these cells, but 
also how far we are from achieving such therapies. Advocacy groups must 
also level with their stakeholders and explain why treatments based on stem 
cells will take such a long time to materialize — and why the wait is worth 
it. At the same time, these organizations must continue to push scientists 
to work harder and achieve results faster, encouraging investigators to 
keep in mind the patients in whose name the research is being conducted 
(and funded).

Editors of scientific journals, as well as mainstream reporters, must shape 
up as well. Research articles of questionable quality shouldn't be accepted 
for publication, even if they are certain to garner significant media 
coverage. Similarly, journalists must resist the temptation to lavish 
attention on every published scientific article with the words "stem cell" 
in the title.

Finally, we would all do well to keep in mind that in contrast to the tidy, 
syncopated tableau of television's "CSI," science in the real world is 
frequently tedious and almost always messy. But there are also moments of 
great clarity and wondrous insight — moments I anticipate we will 
experience with increasing frequency in stem cell research. In the end, I 
suspect embryonic stem cells will evolve into a therapeutic tool even more 
useful than anything we can now envision. But the development of this 
entirely new area of science will take dedication, funding and, above all, 
time. "Genius is eternal patience," Michaelangelo observed. Let us hope 
that for those looking to stem cells for treatment, the wait will not be 
quite so long.

Shaywitz is an endocrinologist and stem cell researcher at Harvard University.

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