Interferon restores replication fork stability and cell viability in BRCA-defective cells via ISG15

DNA replication and repair defects or genotoxic treatments trigger interferon (IFN)-mediated inflammatory responses. However, whether and how IFN signaling in turn impacts the DNA replication process has remained elusive. Here we show that basal levels of the IFN-stimulated gene 15, ISG15, and its conjugation (ISGylation) are essential to protect nascent DNA from degradation. Moreover, IFNβ treatment restores replication fork stability in BRCA1/2-deficient cells, which strictly depends on topoisomerase-1, and rescues lethality of BRCA2-deficient mouse embryonic stem cells. Although IFNβ activates hundreds of genes, these effects are specifically mediated by ISG15 and ISGylation, as their inactivation suppresses the impact of IFNβ on DNA replication. ISG15 depletion significantly reduces cell proliferation rates in human BRCA1-mutated triple-negative, whereas its upregulation results in increased resistance to the chemotherapeutic drug cisplatin in mouse BRCA2-deficient breast cancer cells, respectively. Accordingly, cells carrying BRCA1/2 defects consistently show increased ISG15 levels, which we propose as an in-built mechanism of drug resistance linked to BRCAness.</p

Interferon restores replication fork stability and cell viability in BRCA-defective cells via ISG15

DNA replication and repair defects or genotoxic treatments trigger interferon (IFN)-mediated inflammatory responses. However, whether and how IFN signaling in turn impacts the DNA replication process has remained elusive. Here we show that basal levels of the IFN-stimulated gene 15, ISG15, and its conjugation (ISGylation) are essential to protect nascent DNA from degradation. Moreover, IFNβ treatment restores replication fork stability in BRCA1/2-deficient cells, which strictly depends on topoisomerase-1, and rescues lethality of BRCA2-deficient mouse embryonic stem cells. Although IFNβ activates hundreds of genes, these effects are specifically mediated by ISG15 and ISGylation, as their inactivation suppresses the impact of IFNβ on DNA replication. ISG15 depletion significantly reduces cell proliferation rates in human BRCA1-mutated triple-negative, whereas its upregulation results in increased resistance to the chemotherapeutic drug cisplatin in mouse BRCA2-deficient breast cancer cells, respectively. Accordingly, cells carrying BRCA1/2 defects consistently show increased ISG15 levels, which we propose as an in-built mechanism of drug resistance linked to BRCAness

Comprehensive RNA-Seq Expression Analysis of Sensory Ganglia with a Focus on Ion Channels and GPCRs in Trigeminal Ganglia

The specific functions of sensory systems depend on the tissue-specific expression of genes that code for molecular sensor proteins that are necessary for stimulus detection and membrane signaling. Using the Next Generation Sequencing technique (RNA-Seq), we analyzed the complete transcriptome of the trigeminal ganglia (TG) and dorsal root ganglia (DRG) of adult mice. Focusing on genes with an expression level higher than 1 FPKM (fragments per kilobase of transcript per million mapped reads), we detected the expression of 12984 genes in the TG and 13195 in the DRG. To analyze the specific gene expression patterns of the peripheral neuronal tissues, we compared their gene expression profiles with that of the liver, brain, olfactory epithelium, and skeletal muscle. The transcriptome data of the TG and DRG were scanned for virtually all known G-protein-coupled receptors (GPCRs) as well as for ion channels. The expression profile was ranked with regard to the level and specificity for the TG. In total, we detected 106 non-olfactory GPCRs and 33 ion channels that had not been previously described as expressed in the TG. To validate the RNA-Seq data, in situ hybridization experiments were performed for several of the newly detected transcripts. To identify differences in expression profiles between the sensory ganglia, the RNA-Seq data of the TG and DRG were compared. Among the differentially expressed genes (> 1 FPKM), 65 and 117 were expressed at least 10-fold higher in the TG and DRG, respectively. Our transcriptome analysis allows a comprehensive overview of all ion channels and G protein-coupled receptors that are expressed in trigeminal ganglia and provides additional approaches for the investigation of trigeminal sensing as well as for the physiological and pathophysiological mechanisms of pain

Intubation Practices and Adverse Peri-intubation Events in Critically Ill Patients from 29 Countries

Importance: Tracheal intubation is one of the most commonly performed and high-risk interventions in critically ill patients. Limited information is available on adverse peri-intubation events. Objective: To evaluate the incidence and nature of adverse peri-intubation events and to assess current practice of intubation in critically ill patients. Design, Setting, and Participants: The International Observational Study to Understand the Impact and Best Practices of Airway Management in Critically Ill Patients (INTUBE) study was an international, multicenter, prospective cohort study involving consecutive critically ill patients undergoing tracheal intubation in the intensive care units (ICUs), emergency departments, and wards, from October 1, 2018, to July 31, 2019 (August 28, 2019, was the final follow-up) in a convenience sample of 197 sites from 29 countries across 5 continents. Exposures: Tracheal intubation. Main Outcomes and Measures: The primary outcome was the incidence of major adverse peri-intubation events defined as at least 1 of the following events occurring within 30 minutes from the start of the intubation procedure: cardiovascular instability (either: systolic pressure &lt;65 mm Hg at least once, &lt;90 mm Hg for &gt;30 minutes, new or increase need of vasopressors or fluid bolus &gt;15 mL/kg), severe hypoxemia (peripheral oxygen saturation &lt;80%) or cardiac arrest. The secondary outcomes included intensive care unit mortality. Results: Of 3659 patients screened, 2964 (median age, 63 years; interquartile range [IQR], 49-74 years; 62.6% men) from 197 sites across 5 continents were included. The main reason for intubation was respiratory failure in 52.3% of patients, followed by neurological impairment in 30.5%, and cardiovascular instability in 9.4%. Primary outcome data were available for all patients. Among the study patients, 45.2% experienced at least 1 major adverse peri-intubation event. The predominant event was cardiovascular instability, observed in 42.6% of all patients undergoing emergency intubation, followed by severe hypoxemia (9.3%) and cardiac arrest (3.1%). Overall ICU mortality was 32.8%. Conclusions and Relevance: In this observational study of intubation practices in critically ill patients from a convenience sample of 197 sites across 29 countries, major adverse peri-intubation events - in particular cardiovascular instability - were observed frequently