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Zwart, W.

Publications and source records attributed to Zwart, W..

2 recordsLinked to original sources

DNA end-resection in highly accessible chromatin produces a toxic break

The authors have withdrawn their manuscript whilst they perform additional experiments to test some of their conclusions further. Despite repetitive attempts to reproduce the data shown in figure 2I, we have failed to obtain convincing evidence that chemical inhibition of Mre11 can improve the fitness of cells exposed to the so-called "halt" breaks. Upon re-analysis of the raw data used to compose figure 2I, we noted inconsistencies in the inclusion of datapoints, for which a satisfactory motivation was not apparent. In order to reproduce the experiments with the DNA-PK inhibitor, we ordered new batches of this compound, but noticed that the IC50 was significantly lower than that of the earlier batch (as determined in suppl. fig.1). While this might be due to a difference in batches, the IC50 of the newer batches was more comparable to the IC50 of this compound described for other cell lines. This sheds doubts on the quality of the batch used for the experiments shown in our manuscript, and we no longer wish to draw any conclusions based on these experiments. The authors hope that future experiments can resolve if open chromatin does indeed produce a potentially more toxic DNA break. The authors do not wish this work to be cited as reference for the project. If you have any questions, please contact the corresponding author.

cell biology

The genomic landscape of metastatic castration-resistant prostate cancers using whole genome sequencing reveals multiple distinct genotypes with potential clinical impact

Here we present whole-genome sequencing (WGS) analysis of fresh-frozen metastatic biopsies from 197 castration-resistant prostate cancer patients. Using hierarchical unsupervised clustering based on genomic aberrations only, we defined eight different clusters. We detected four distinct and potentially clinically relevant genotypes harboring unique genomic features, including: 1) Microsatellite Instability; 2) Homologous Recombination Deficiency (HRD) with enriched genomic deletions and BRCA2 aberrations; 3) tandem duplication phenotype associated with biallelic CDK12 mutations; and 4) a subgroup enriched for chromothripsis events. Our data suggest that classifying patients using WGS characteristics may improve classification of HRD patients. Moreover, we confirmed that important regulators of AR-mediated signaling are located in non-coding regions. Using ChIP sequencing data, we showed that the amplified AR and MYC promoter regions contain open chromatin and bind AR, suggesting a role in AR mediated biology. Thus, high-resolution WGS may be used to improve patient stratification.

cancer biology