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 Following communications with journal editors, two of these TPD52L2 publications have been retracted.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

For decades, neuroscientists have used enriched preparations of synaptic particles called synaptosomes to study synapse function. However, the interpretation of corresponding data is problematic as synaptosome preparations contain multiple types of synapses and non-synaptic neuronal and glial contaminants. We established a novel Fluorescence Activated Synaptosome Sorting (FASS) method that substantially improves conventional synaptosome enrichment protocols and enables high-resolution biochemical analyses of specific synapse subpopulations. Employing knock-in mice with fluorescent glutamatergic synapses, we show that FASS isolates intact ultrapure synaptosomes composed of a resealed presynaptic terminal and a postsynaptic density as assessed by light and electron microscopy. FASS synaptosomes contain bona fide glutamatergic synapse proteins but are almost devoid of other synapse types and extrasynaptic or glial contaminants. We identified 163 enriched proteins in FASS samples, of which FXYD6 and Tpd52 were validated as new synaptic proteins. FASS purification thus enables high-resolution biochemical analyses of specific synapse subpopulations in health and disease.

Amplification of the MYCN oncogene predicts treatment resistance in childhood neuroblastoma. We used a MYC target gene signature that predicts poor neuroblastoma prognosis to identify the histone chaperone, FAcilitates Chromatin Transcription (FACT), as a crucial mediator of the MYC signal and a therapeutic target in the disease. FACT and MYCN expression created a forward feedback loop in neuroblastoma cells that was essential for maintaining mutual high expression. FACT inhibition by the small molecule curaxin compound, CBL0137, markedly reduced tumor initiation and progression in vivo. CBL0137 exhibited strong synergy with standard chemotherapy by blocking repair of DNA damage caused by genotoxic drugs, thus creating a synthetic lethal environment in MYCN-amplified neuroblastoma cells and suggesting a treatment strategy for MYCN-driven neuroblastoma.