Nature 510, 407–411 (2014); doi:10.1038/nature13444

Queen Mary University London notified Nature and University College London that there is reason to question the provenance of the data for Fig. 5b, d, e of this Letter (Fig. 5a, c data are unaffected). Ongoing studies are investigating the reported effect of p110δ inhibition in the pancreatic cancer mouse model. We therefore wish to withdraw these figure panels and associated text from the published paper. This does not affect the overall conclusion of the manuscript or any of the other experiments performed for this study as they repeat effects shown using other model systems in the paper (see Supplementary Information for raw data of experiments). We apologise for the inconvenience that this may have caused.