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Wagstaff, J.

Publications and source records attributed to Wagstaff, J..

3 recordsLinked to original sources

A precision oncology-focused deep learning framework for personalized selection of cancer therapy

Precision oncology matches tumors to targeted therapies based on the presence of actionable molecular alterations. However, most tumors lack actionable alterations, restricting treatment options to cytotoxic chemotherapies for which few data-driven prioritization strategies currently exist. Here, we report an integrated computational/experimental treatment selection approach applicable for both chemotherapies and targeted agents irrespective of actionable alterations. We generated functional drug response data on a large collection of patient-derived tumor models and used it to train ScreenDL, a novel deep learning-based cancer drug response prediction model. ScreenDL leverages the combination of tumor omic and functional drug screening data to predict the most efficacious treatments. We show that ScreenDL accurately predicts response to drugs with diverse mechanisms, outperforming existing methods and approved biomarkers. In our preclinical study, this approach achieved superior clinical benefit and objective response rates in breast cancer patient-derived xenografts, suggesting that testing ScreenDL in clinical trials may be warranted.

cancer biology↗

TASOR is a pseudo-PARP that directs HUSH complex assembly and epigenetic transposon control

SummaryThe Human Silencing Hub (HUSH) complex epigenetically represses retroviruses, transposons and genes in vertebrates. HUSH therefore maintains genome integrity and is central in the interplay between intrinsic immunity, transposable elements and transcriptional regulation. Comprising three subunits - TASOR, MPP8 and Periphilin - HUSH regulates SETDB1-dependent deposition of the transcriptionally repressive epigenetic mark H3K9me3 and recruits MORC2 to modify local chromatin structure. However the mechanistic roles of each HUSH subunit remain undetermined. Here we show that TASOR lies at the heart of HUSH, providing a platform for assembling the other subunits. Targeted epigenomic profiling supports the model that TASOR binds and regulates H3K9me3 specifically over LINE-1 repeats and other repetitive exons in transcribed genes. We find TASOR associates with several components of the nuclear RNA processing machinery and its modular domain architecture bears striking similarities to that of Chp1, the central component of the yeast RNA-induced transcriptional silencing (RITS) complex. Together these observations suggest that an RNA intermediate may be important for HUSH activity. We identify the TASOR domains necessary for HUSH assembly and transgene repression. Structural and genomic analyses reveal that TASOR contains a poly-ADP ribose polymerase (PARP) domain dispensable for assembly and chromatin localization, but critical for epigenetic regulation of target elements. This domain contains a degenerated and obstructed active site and has hence lost catalytic activity. Together our data demonstrate that TASOR is a pseudo-PARP critical for HUSH complex assembly and H3K9me3 deposition over its genomic targets.

molecular biology↗

Cryo-EM structure of the MinCD copolymeric filament from Pseudomonas aeruginosa at 3.1 A resolution

Positioning of the division site in many bacterial species relies on the MinCDE system, which prevents the cytokinetic Z-ring from assembling anywhere but the mid-cell, through an oscillatory diffusion-reaction mechanism. MinD dimers bind to membranes and, via their partner MinC, inhibit the polymerisation of cell division protein FtsZ into the Z-ring. MinC and MinD form polymeric assemblies in solution and on cell membranes. Here, we report the high-resolution cryo-EM structure of the copolymeric filaments of Pseudomonas aeruginosa MinCD. The filaments consist of three protofilaments made of alternating MinC and MinD dimers. The MinCD protofilaments are almost completely straight and assemble as single protofilaments on lipid membranes, which we also visualised by cryo-EM.

molecular biology↗