Pan-cancer association of DNA repair deficiencies with whole-genome mutational patterns.

DNA repair deficiencies in cancers may result in characteristic mutational patterns, as exemplified by deficiency of and efficacy prediction for PARP inhibitors. We trained and evaluated predictive models for loss-of-function (LOF) of 145 individual DNA damage response genes based on genome-wide mutational patterns, including structural variants, indels, and base-substitution signatures. We identified 24 genes whose deficiency could be predicted with good accuracy, including expected mutational patterns for , , , and LOF variants.

Computational and cellular studies reveal structural destabilization and degradation of MLH1 variants in Lynch syndrome.

Defective mismatch repair leads to increased mutation rates, and germline loss-of-function variants in the repair component MLH1 cause the hereditary cancer predisposition disorder known as Lynch syndrome. Early diagnosis is important, but complicated by many variants being of unknown significance. Here we show that a majority of the disease-linked MLH1 variants we studied are present at reduced cellular levels.

Visualisation of γH2AX foci caused by heavy ion particle traversal; distinction between core track versus non-track damage.

Heavy particle irradiation produces complex DNA double strand breaks (DSBs) which can arise from primary ionisation events within the particle trajectory. Additionally, secondary electrons, termed delta-electrons, which have a range of distributions can create low linear energy transfer (LET) damage within but also distant from the track. DNA damage by delta-electrons distant from the track has not previously been carefully characterised.

Gold amides as anticancer drugs: synthesis and activity studies.

Modular gold amide chemotherapeutics: Access to modern chemotherapeutics with robust and flexible synthetic routes that are amenable to extensive customisation is a key requirement in drug synthesis and discovery. A class of chiral gold amide complexes featuring amino acid derived ligands is reported herein. They all exhibit in vitro cytotoxicity against two slow growing breast cancer cell lines with limited toxicity towards normal epithelial cells.

Analysis of human syndromes with disordered chromatin reveals the impact of heterochromatin on the efficacy of ATM-dependent G2/M checkpoint arrest.

Heterochromatin (HC) poses a barrier to γH2AX focus expansion and DNA double-strand break (DSB) repair, the latter being relieved by ATM-dependent KAP-1 phosphorylation. Using high-resolution imaging, we show here that the HC superstructure markedly restricts ATM signaling to cell cycle checkpoint proteins. The impact of HC is greater than anticipated from the percentage of HC-DNA and, in distinction to DSB repair, ATM only partly overcomes the constraints posed by HC.