Researcher at Japan stem cell institute falsified nearly all images in 2017 paper

Shinya Yamanaka

An investigation by Kyoto University in Japan has found a researcher guilty of falsifying all but one of the figures in a 2017 stem cell paper.

Yesterday, Kyoto University announced that the paper’s first author, Kohei Yamamizu, had fabricated and falsified data in the Stem Cell Reports paper. According to the investigation report, none of the other authors were involved in the data manipulation.

Yamamizu works at the Center for iPS cell Research and Application (CiRA) at Kyoto University, directed by Shinya Yamanaka, a Nobel Prize winner for his pioneering work in stem cell biology.

A spokesperson for the journal told us that the authors disclosed the problems last week and Stem Cell Reports will be retracting the paper, published last February.

In the university’s official statement, Yamanaka said:

I am saddened to report that our internal investigation has concluded that a specially-appointed assistant professor at CiRA falsified and fabricated the data used in a 2017 research publication for which he was the first and corresponding author.  

In his university announcement, Yamanaka apologized for the situation:

As CiRA Director, I feel a strong responsibility for not having been able to prevent research misconduct at our institute and sincerely apologize to all who support us and our research activities…Kyoto University is now deliberating its punishment toward the above specially-appointed assistant professor, the professor who supervised the researcher and myself.

Yamamizu is still listed as an assistant professor at the university; the university did not release the name of his supervisor.  

We reached out to Jun Yamashita, the 2017 paper’s last author and the principal investigator in the department where Yamamizu works, as well as Yamamizu.

A university spokesperson, who responded on behalf of Yamanaka, told Retraction Watch:

The main conclusions of the paper depended heavily on the fraudulent data.

The spokesperson also explained that the university has not received allegations regarding other papers by Yamamizu, and his other work is not in question.

According to the university’s announcement, last year, the university was informed about potential problems with images in the paper. The university “attempted to recreate some of the figures presented in the paper using original data,” but “found the conclusions in the paper were not consistent with the preserved data.”

In July, the university’s initial inquiry prompted a formal investigation of the paper, In Vitro Modeling of Blood-Brain Barrier with Human iPSC-Derived Endothelial Cells, Pericytes, Neurons, and Astrocytes via Notch Signaling.” The paper has been cited nine times, according to Clarivate Analytics’ Web of Science.

The university, which conducted its investigation from September 11 to January 9, found that Yamamizu had falsified data in the six main figures in the paper, as well as in five of the six supplementary figures.

In his statement, Yamanaka wrote:

We take misconduct very seriously. We will reevaluate our research management to strengthen our research ethics and to regain public trust in our research.

According to the Mainichi:

CiRA, the research institute for induced pluripotent stem (iPS) cells for which Yamanaka won the Nobel Prize for medicine in 2012, has a strict research management system to prevent wrongdoings. All researchers get their notes on experiments checked at least once every three months and if a research paper is to be published, the researcher must submit research materials such as original data and images. ..At the same time, the center had only made its researchers submit study materials, but failed to check their contents in detail. In reality, the submission rate of such data was not 100 percent…when Yamanaka checked Yamamizu’s notes for the first time after the issue surfaced, he thought they were insufficient.

In 2014, the Nobel laureate apologized for so-called “poor record keeping,” according to the Wall Street Journal, after questions arose regarding a 2000 paper on which he was lead author. Although a Kyoto investigation confirmed the paper’s conclusions, Yamanaka said he no longer had lab records to support the images.

Hat tip: Lemon-Stoism, Author of world fluctuation watch

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8 thoughts on “Researcher at Japan stem cell institute falsified nearly all images in 2017 paper”

  1. … “specially-appointed assistant professor”. What that means? Who were behind that appointment and created secure margin for that professor for falsification of data and misconduct?

  2. “specially-appointed” simply means “fixed-term” (i.e., untenured). Most young postdocs, assistant profs and associate profs in Japan are “specially-appointed”.

  3. “his other work is not in question”. Perhaps it will be now.

    The problem we all have, of course, is that unless WE have access to the original data of researchers, we rely 100% on the word of any given researchers. Does this need to change?

    Perhaps more sophisticated and organised science-cheaters are not caught as they do more than simply splice gels and manipulate images that are easily found with keen eyes and computer software.

    1. I’m now curious how the case came into light in the first place. If you look at the paper, the manipulation is not so obvious. Maybe the suspicion was raised because of the error bars…?

  4. This again damages the reputation and credibility of the general Japanese scientific community and, in particular, of the Japanese steam cell scientific community. I have no more confidence in Japanese cell related research anymore….

  5. This will only get worse the more competition there is and the more that jobs depend on getting high impact papers by yourself or with a few people who do work separately without anyone checking their experiments. Change the system to mandate experiments performed by independent lab members (without collusion) and these cases will go away.

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