Although the retraction notice itself contains relatively little information, we’ve obtained a letter from the last author — Jun-Li Luo of The Scripps Research Institute in Jupiter, Florida — to the editor-in-chief of Cell Death and Differentiation that says a bit more.
According to the letter, after receiving the anonymous email, Luo conducted an investigation, contacting co-authors who contributed each of the figures in question. Although Luo writes that he has no reason to suspect fraud, the researchers were not able to provide some of the original data.
PubPeer commenters have questioned figures 1, 3, 4, 5, 6 and 7 in the study, “IKKα-mediated biogenesis of miR-196a through interaction with Drosha regulates the sensitivity of cancer cells to radiotherapy.”
In the letter, Luo tells Gerry Melino, co-editor-in-chief of the journal from the University of Leicester, UK, that figures 3D and 3E were provided by the study’s first author, Xing Fang, adding:
He said he modified these two figures when the FITC-RNA gel photos were converted into black and white pictures, and claimed the original FITC-RNA gel photos were lost.
According to the letter, figures 5a, 5c and 7c were contributed by Xueping Feng, the study’s joint corresponding author. Feng, writes Luo, said that
she checked the original data and found that Fig. 5a and 5c were indeed [accidentally] mixed. Fig. 7c is the microscope photos of the in situ hybridization in paraffin-embedded human NPC tissue sections.
Feng did not modify these images, Luo’s letter says, but
It is surprising for Dr. Feng and us that the pictures shown in Fig. 7c contains some similar cells, as we did these experiments on the slides of 116 NPC samples, and there were so many (hundreds of) representative photos can be used.
The group tried to find more information about figure 7c, but were unsuccessful, Luo writes.
We reached out to Melino to verify the letter, but he was unable to respond to questions before deadline.
Here’s the retraction notice, issued on September 16:
Following the identification of discrepancies between images and the data, and at the request of the authors, we are retracting the following paper: “IKKα -mediated biogenesis of miR-196a through interaction with Drosha regulates the sensitivity of cancer cells to radiotherapy” by Fang et al. Cell Death Differ 2016 Sep 1;23(9):1471–82. doi: 10.1038/cdd.2016.32.
The paper was published online in April.
Both Xing Fang and Xueping Feng are affiliated with Central South University in Changsha, China, as well as The Scripps Research Institute. According to this document we found online, the Union for International Cancer Control awarded Feng with the Yamagiwa-Yoshida Memorial International Cancer Study Grant in Spring 2014 to travel to the U.S. and work with Luo.
An email to Feng could not be delivered, and we couldn’t find the contact details for Fang. A spokesperson from the Scripps Research Institute said it is not the institution’s policy to provide contact details for their employees.
Luo adds in the letter that
there appear to be problems and because we are unable to provide some of the original data that was used to create the photos in these figures, I cannot defend with absolute certainty the conclusions drawn from them.
Before inclusion into scientific literature, the experiments need to be repeated, Luo says in the letter, adding:
Therefore, I would like to publish a retraction of our current paper. I apologize sincerely for the trouble this has caused.
We’ll update the post with anything else we learn.
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