Identifying metabolic adaptations characteristic of cardiotoxicity using paired transcriptomics and metabolomics data integrated with a computational model of heart metabolism.

Improvements in the diagnosis and treatment of cancer have revealed long-term side effects of chemotherapeutics, particularly cardiotoxicity. Here, we present paired transcriptomics and metabolomics data characterizing in vitro cardiotoxicity to three compounds: 5-fluorouracil, acetaminophen, and doxorubicin. Standard gene enrichment and metabolomics approaches identify some commonly affected pathways and metabolites but are not able to readily identify metabolic adaptations in response to cardiotoxicity. The paired data was integrated with a genome-scale metabolic network reconstruction of the heart to identify shifted metabolic functions, unique metabolic reactions, and changes in flux in metabolic reactions in response to these compounds. Using this approach, we confirm previously seen changes in the p53 pathway by doxorubicin and RNA synthesis by 5-fluorouracil, we find evidence for an increase in phospholipid metabolism in response to acetaminophen, and we see a shift in central carbon metabolism suggesting an increase in metabolic demand after treatment with doxorubicin and 5-fluorouracil.

Metabolic modeling of sex-specific liver tissue suggests mechanism of differences in toxicological responses.

Male subjects in animal and human studies are disproportionately used for toxicological testing. This discrepancy is evidenced in clinical medicine where females are more likely than males to experience liver-related adverse events in response to xenobiotics. While previous work has shown gene expression differences between the sexes, there is a lack of systems-level approaches to understand the direct clinical impact of these differences. Here, we integrate gene expression data with metabolic network models to characterize the impact of transcriptional changes of metabolic genes in the context of sex differences and drug treatment. We used Tasks Inferred from Differential Expression (TIDEs), a reaction-centric approach to analyzing differences in gene expression, to discover that several metabolic pathways exhibit sex differences including glycolysis, fatty acid metabolism, nucleotide metabolism, and xenobiotics metabolism. When TIDEs is used to compare expression differences in treated and untreated hepatocytes, we find several subsystems with differential expression overlap with the sex-altered pathways such as fatty acid metabolism, purine and pyrimidine metabolism, and xenobiotics metabolism. Finally, using sex-specific transcriptomic data, we create individual and averaged male and female liver models and find differences in the pentose phosphate pathway and other metabolic pathways. These results suggest potential sex differences in the contribution of the pentose phosphate pathway to oxidative stress, and we recommend further research into how these reactions respond to hepatotoxic pharmaceuticals.

The primary mechanism of cytotoxicity of the chemotherapeutic agent CX-5461 is topoisomerase II poisoning.

Small molecules can affect many cellular processes. The disambiguation of these effects to identify the causative mechanisms of cell death is extremely challenging. This challenge impacts both clinical development and the interpretation of chemical genetic experiments. CX-5461 was developed as a selective RNA polymerase I inhibitor, but recent evidence suggests that it may cause DNA damage and induce G-quadraplex formation. Here we use three complimentary data mining modalities alongside biochemical and cell biological assays to show that CX-5461 exerts its primary cytotoxic activity through topoisomerase II poisoning. We then show that acquired resistance to CX-5461 in previously sensitive lymphoma cells confers collateral resistance to the topoisomerase II poison doxorubicin. Doxorubicin is already a frontline chemotherapy in a variety of hematopoietic malignancies, and CX-5461 is being tested in relapse/refractory hematopoietic tumors. Our data suggest that the mechanism of cell death induced by CX-5461 is critical for rational clinical development in these patients. Moreover, CX-5461 usage as a specific chemical genetic probe of RNA polymerase I function is challenging to interpret. Our multimodal data-driven approach is a useful way to detangle the intended and unintended mechanisms of drug action across diverse essential cellular processes.

Interim Foundation Year One (FiY1) and preparedness for foundation year 1: A national survey of UK foundation doctors.

BACKGROUND: Induction programmes aim to ease the transition from medical student to doctor. The interim foundation year 1 (FiY1) placement, introduced in the first COVID-19 wave, provided experience in advance of the Foundation Year 1 (FY1) start in August; providing more time and enhanced responsibilities than traditional induction programmes. This study examines the effects of the FiY1 placement on anxiety levels and preparedness for FY1. METHODS: This was a descriptive cross-sectional study using data from four cohorts of FY1s who completed the online National FY1 induction survey from 2017 to 2020 (n = 4766). Questions evaluated self-reported preparedness and anxiety levels. Differences in preparedness and anxiety levels of FiY1 and non-FiY1 participants in 2020, and the 2017-2019 participants (non-FiY1 controls), were evaluated. RESULTS: FiY1s in 2020 reported higher self-reported preparedness (79%) than non-FiY1s (54%) in 2020 (p = <0.001) and the control 2017-2019 cohort (63.8%) (p < 0.001). Fewer FiY1s experienced pathological anxiety (29.3% versus 40.8% for non-FiY1s; p = 0.001). CONCLUSION: Time spent in an FiY1 role is associated with an increase in self-perceptions of preparedness and a reduction in anxiety. These data indicate that time spent in an FiY1 role may have utility in further improving the transition period from medical school to FY1.

Synthesis, structure and anticancer properties of new biotin- and morpholine-functionalized ruthenium and osmium half-sandwich complexes.

Ruthenium (Ru) and osmium (Os) complexes are of sustained interest in cancer research and may be alternative to platinum-based therapy. We detail here three new series of ruthenium and osmium complexes, supported by physico-chemical characterizations, including time-dependent density functional theory, a combined experimental and computational study on the aquation reactions and the nature of the metal-arene bond. Cytotoxic profiles were then evaluated on several cancer cell lines although with limited success. Further investigations were, however, performed on the most active series using a genetic approach based on RNA interference and highlighted a potential multi-target mechanism of action through topoisomerase II, mitotic spindle, HDAC and DNMT inhibition.

Metabolic modeling of sex-specific tissue predicts mechanisms of differences in toxicological responses.

Male subjects in animal and human studies are disproportionately used for toxicological testing. This discrepancy is evidenced in clinical medicine where females are more likely than males to experience liver-related adverse events in response to xenobiotics. While previous work has shown gene expression differences between the sexes, there is a lack of systems-level approaches to understand the direct clinical impact effect of these differences. Here, we integrate gene expression data with metabolic network models to characterize the impact of transcriptional changes of metabolic genes in the context of sex differences and drug treatment. We used Tasks Inferred from Differential Expression (TIDEs), a reaction-centric approach to analyzing differences in gene expression, to discover that androgen, ether lipid, glucocorticoid, tryptophan, and xenobiotic metabolism have more activity in the male liver, and serotonin, melatonin, pentose, glucuronate, and vitamin A metabolism have more activity in the female liver. When TIDEs is used to compare expression differences in treated and untreated hepatocytes, we see little response in those sex-altered subsystems, and the largest differences are in subsystems related to lipid metabolism. Finally, using sex-specific transcriptomic data, we create individual and averaged male and female liver models and find differences in the import of bile acids and salts. This result suggests that the sexually dimorphic behavior of the liver may be caused by differences in enterohepatic recirculation, and we suggest an investigation into sex-specific microbiome composition as an avenue of further research. Author Summary: Male-bias in clinical testing of drugs has led to a disproportionate number of hepatotoxic events in women. Previous works use gene-by-gene differences in biological sex to explain this discrepancy, but there is little focus on the systematic interactions of these differences. To this end, we use a combination of gene expression data and metabolic modeling to compare metabolic activity between the male and female liver and treated and untreated hepatocytes. We find several subsystems with differential activity in each sex; however, when comparing these subsystems with those pathways altered by hepatotoxic agents, we find little overlap. To explore these differences on a reaction-by-reaction basis, we use the same sex-specific transcriptomic data to contextualize the previously published Human1 human cell metabolic model. In these models we find a difference in flux for the import of bile acids and salts, suggesting a potential difference in enterohepatic circulation. These findings can help guide future drug design, toxicological testing, and sex-specific research to better account for the entire human population.

Excessive concentrations of kinase inhibitors in translational studies impede effective drug repurposing.

Drug repositioning seeks to leverage existing clinical knowledge to identify alternative clinical settings for approved drugs. However, repositioning efforts fail to demonstrate improved success rates in late-stage clinical trials. Focusing on 11 approved kinase inhibitors that have been evaluated in 139 repositioning hypotheses, we use data mining to characterize the state of clinical repurposing. Then, using a simple experimental correction with human serum proteins in in vitro pharmacodynamic assays, we develop a measurement of a drug's effective exposure. We show that this metric is remarkably predictive of clinical activity for a panel of five kinase inhibitors across 23 drug variant targets in leukemia. We then validate our model's performance in six other kinase inhibitors for two types of solid tumors: non-small cell lung cancer (NSCLC) and gastrointestinal stromal tumors (GISTs). Our approach presents a straightforward strategy to use existing clinical information and experimental systems to decrease the clinical failure rate in drug repurposing studies.

Self-assembled ruthenium and osmium nanosystems display a potent anticancer profile by interfering with metabolic activity.

We disclose novel amphiphilic ruthenium and osmium complexes that auto-assemble into nanomedicines with potent antiproliferative activity by inhibition of mitochondrial respiration. The self-assembling units were rationally designed from the [M(p-cymene)(1,10-phenanthroline)Cl]PF6 motif (where M is either RuII or OsII) with an appended C16 fatty chain to achieve high cellular activity, nano-assembling and mitochondrial targeting. These amphiphilic complexes block cell proliferation at the sub-micromolar range and are particularly potent towards glioblastoma neurospheres made from patient-derived cancer stem cells. A subcutaneous mouse model using these glioblastoma stem cells highlights one of our C16 OsII nanomedicines as highly successful in vivo. Mechanistically, we show that they act as metabolic poisons, strongly impairing mitochondrial respiration, corroborated by morphological changes and damage to the mitochondria. A genetic strategy based on RNAi gave further insight on the potential involvement of microtubules as part of the induced cell death. In parallel, we examined the structural properties of these new amphiphilic metal-based constructs, their reactivity and mechanism.

Mapping the Landscape of Surgical Registries in the United Kingdom: A Review According to the SWiM Methodology.

BACKGROUND: Well-designed surgical registries are essential for high-quality patient centred evaluation of implantable devices and surgical procedures. The importance of registries was highlighted in the recent Cumberlege report that detailed important innovation failures such as the use of vaginal mesh. Many surgical registries exist, but it is currently unclear how different registries are funded, governed, designed, and how their databases are hosted and utilised. There is therefore a need to understand the variation and characteristics of existing surgical registries to identify limitations and make recommendations for improvement. This work aims to understand the characteristics and heterogeneity in the design, governance, and function of existing surgical registries in the United Kingdom (UK). METHODS: Existing surgical registries will be identified using multiple data sources including surgical society websites; search engine review; a targeted search of the Medline and Embase databases and expert knowledge. The data identified were reviewed following the synthesis without meta-analysis (SWiM) methodology. This information will be gathered from sources in the public domain only to fully understand registry transparency for professionals and the public. Details of each registry including disease area/condition/device evaluated; types of outcomes collected; governance, consent, and oversight; linkage to other datasets and funding will be extracted using a standardised data extraction tool. Characteristics of identified registries will be summarised into a narrative review. DISSEMINATION: Findings will be presented at national and international conferences and published in peer-reviewed journals. Results will be presented to key stakeholders including surgeons, methodologists, trialists, regulators, data managers and patients to provide an up-to-date description of the current state of surgical registries in the UK. This work will inform a consensus process to agree how the design of new and existing registries can be optimised to support high quality research to benefit patients and the NHS. HIGHLIGHTS: Well-designed surgical registries are essential for high-quality patient centred evaluation of implantable devices and surgical proceduresPresently there is limited understanding on how these registries are designed, governed, what data they collect and how this data is utilised for research.This review aims to map the landscape of surgical registries in the UK, and understand how they are optimised for research.