Thursday, February 20, 2014

It’s a big breakthrough. Wait, maybe, maybe not. Taking a second look at STAP

It’s always fascinating watching the arc of a news story. I woke up on January 29th to news, as the BBC World Service put it, “of a big breakthrough in stem cell research.” The reporter then went on to explain how scientists had created a whole new type of pluripotent stem cell – the kind that can change into any other kind of cell – by simply “shocking” a normal cell by immersing it in acid or subjecting it to other kinds of stress.

News outlets around the globe quickly picked up the story and ran their own versions of it. For days the media was positively giddy with stories about this new discovery – called stimulus-triggered acquisition of pluripotency (STAP) cells – with lots of speculation about how this could change the science and possibly even eliminate the need for embryonic stem cells.

We blogged about it February 3, but with the word “caveats” in the headline and the bulk of the post devoted to debunking the hype in the news coverage and discussing the need for further validation from the scientific community.

In the last week the tide has certainly turned. A growing number of news outlets, journals and blogs have taken a step back and begun to question not just some of the claims about STAP cells, but whether these cells even exist.

The original study - by Haruko Obokata of the RIKEN Center for Developmental Biology (CDB) in Kobe, Japan, and researchers at Harvard Medical School in Boston – was published in the journal Nature But just a week later anonymous bloggers at the PubPeer website raised questions about certain images used in the manuscript, suggesting they might have been altered.

Over the next week or so other scientists joined in expressing their doubts. U.C. Davis stem cell scientist and avid blogger Dr. Paul Knoepfler (we fund some of his work) has written extensively on this topic and quoted a piece from a writer with Nature, the publication that printed the original story, who reported that other scientists who had tried to replicate the work failed, saying:
“None of ten prominent stem-cell scientists who responded to a questionnaire from Nature has had success.”
Knoepfler has charted the growing uncertainty about STAP cells by doing a weekly poll among his readers (a very scientifically literate group) about whether they believe these cells are real. In week 1 there was a clear inclination among those who voted in favor of them being real. By week 2 that had changed with the numbers who believed in them equally divided, and a growing number of people on the fence.

The news that other scientists haven’t been able to replicate the experiments has now led the Riken Institute in Japan, where the lead researcher in the study works, to carry out its own investigation.

And so now the news is all about the doubts and uncertainty. How quickly the news coverage has changed, racing from celebration to consternation. And yet just because this is the latest swing in the STAP story it doesn’t mean that the research won’t turn out to be valid, or that the findings won’t ultimately prove to be enormously important.

Science rarely progresses in a simple, straight direction. Things that we thought were breakthroughs sometimes turn out to be wrong turns. Things we thought of minor importance sometimes turn out to be very important indeed. We can only find out which is which by constant examination of the data, by doing new experiments and by keeping an open mind.

What this series of stories shows is not that these scientists made a big mistake – we don’t know that. It just reminds us we all need to be very careful about leaping to assumptions about any potential breakthrough.

To quote the old Russian proverb – so beloved by President Reagan - Доверяй, но проверяй (doveryai, no proveryai). Which means Trust, but Verify.

 kevin mccormack

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