Striking similarities between publications from China describing single gene knockdown experiments in human cancer cell lines

International audienceComparing 5 publications from China that described knockdowns of the human TPD52L2 gene in human cancer cell lines identified unexpected similarities between these publications, flaws in experimental design, and mis-matches between some described experiments and the reported results. Following communications with journal editors, two of these TPD52L2 publications have been retracted. One retraction notice stated that while the authors claimed that the data were original, the experiments had been out-sourced to a biotechnology company. Using search engine queries, automatic text-analysis, different similarity measures, and further visual inspection, we identified 48 examples of highly similar papers describing single gene knockdowns in 1–2 human cancer cell lines that were all published by investigators from China. The incorrect use of a particular TPD52L2 shRNA sequence as a negative or non-targeting control was identified in 30/48 (63%) of these publications, using a combination of Google Scholar searches and visual inspection. Overall, these results suggest that some publications describing the effects of single gene knockdowns in human cancer cell lines may include the results of experiments that were not performed by the authors. This has serious implications for the validity of such results, and for their application in future research