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GBM accounts for most of the fatal brain cancer cases, making it one of the deadliest tumor types. GBM is characterized by severe progression and poor prognosis with a short survival upon conventional chemo- and radiotherapy. In order to improve therapeutic efficiency, considerable efforts have been made to target various features of GBM. One of the targetable features of GBM is the rewired lipid metabolism that contributes to the tumor's aggressive growth and penetration into the surrounding brain tissue. Lipid reprogramming allows GBM to acquire survival, proliferation, and invasion benefits as well as supportive modulation of the tumor microenvironment. Several attempts have been made to find novel therapeutic approaches by exploiting the lipid metabolic reprogramming in GBM. In recent studies, various components of de novo lipogenesis, fatty acid oxidation, lipid uptake, and prostaglandin synthesis have been considered promising targets in GBM. Emerging data also suggest a significant role hence therapeutic potential of the endocannabinoid metabolic pathway in GBM. Here we review the lipid-related GBM characteristics in detail and highlight specific targets with their potential therapeutic use in novel antitumor approaches.

Derailed cytokine and immune cell networks account for the organ damage and the clinical severity of COVID-19 (refs. 1-4 ). Here we show that SARS-CoV-2, like other viruses, evokes cellular senescence as a primary stress response in infected cells. Virus-induced senescence (VIS) is indistinguishable from other forms of cellular senescence and is accompanied by a senescence-associated secretory phenotype (SASP), which comprises pro-inflammatory cytokines, extracellular-matrix-active factors and pro-coagulatory mediators 5-7 . Patients with COVID-19 displayed markers of senescence in their airway mucosa in situ and increased serum levels of SASP factors. In vitro assays demonstrated macrophage activation with SASP-reminiscent secretion, complement lysis and SASP-amplifying secondary senescence of endothelial cells, which mirrored hallmark features of COVID-19 such as macrophage and neutrophil infiltration, endothelial damage and widespread thrombosis in affected lung tissue 1,8,9 . Moreover, supernatant from VIS cells, including SARS-CoV-2-induced senescence, induced neutrophil extracellular trap formation and activation of platelets and the clotting cascade. Senolytics such as navitoclax and a combination of dasatinib plus quercetin selectively eliminated VIS cells, mitigated COVID-19-reminiscent lung disease and reduced inflammation in SARS-CoV-2-infected hamsters and mice. Our findings mark VIS as a pathogenic trigger of COVID-19-related cytokine escalation and organ damage, and suggest that senolytic targeting of virus-infected cells is a treatment option against SARS-CoV-2 and perhaps other viral infections., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

Introduction: After atrial fibrillation (AF) ablation, oral anticoagulation (OAC) is recommended if stroke risk as assessed by CHA 2 DS 2 -VASc score is high. However, patients without AF are often reluctant to take daily OAC. We describe outcome using as needed nonvitamin K antagonist (NOACs) guided by pulse monitoring to detect AF following successful ablation., Methods and Results: We identified 99 patients (84% male, age 64 ± 8 years), CHA 2 DS 2 -VASc score greater than or equal to 1 in men and greater than or equal to 2 in women (median 2, range 1-6), capable of pulse assessment twice daily and no AF on extended monitoring after AF ablation. All patients were instructed to start NOAC if AF >1 hour or recurrent shorter episodes. Duration of NOAC use after restart was typically 2 to 4 weeks. After 30 ± 14 months (total 244 patient-years), 22 patients (22%) transitioned to daily NOAC because of noncompliance with pulse assessment or patient preference (six patients) or because of suspected or documented AF episode(s) in 16 (16%) patients. Of the remaining 77 (78%), 14 (14%) used NOACs but did not transition back to daily use, most (10 patients) with single use (seven patients) or non-AF rhythm (three patients) documented. There was only one thromboembolic event (0.4%/yr of follow-up) in patient without AF and one mild bleeding event (epistaxis)., Conclusion: The use of as needed NOACs when AF is suspected with pulse monitoring is effective and safe to maintain low risk of stroke and bleeding after successful ablation. Transition back to daily NOAC use should be anticipated in about one quarter of patients., (© 2019 Wiley Periodicals, Inc.)

A mutant screen has been designed to isolate mutants in Saccharomyces cerevisiae deficient in spore wall dityrosine. As shown by electron microscopy, most of the mutant spores lacked only the outermost, dityrosine-rich layer of the spore wall. Mutant dit101, however, was additionally lacking the chitosan layer of the spore wall. Chemical measurements showed that this mutant does not synthesize chitosan during sporulation. The mutant spores were viable but sensitive to lytic enzymes (glusulase or zymolyase). Unlike most of the dit-mutants, dit101 did show a distinctive phenotype in vegetative cells: they grew normally but contained very little chitin and were therefore resistant to the toxic chitin-binding dye, Calcofluor White. The cells showed barely detectable staining of the walls with Calcofluor White or primulin. The decrease in the amount of chitin in vegetative cells and the absence of chitosan in spores suggested that the mutant dit101 could be defective in a chitin synthase. Indeed, a genomic yeast clone harboring the gene, CSD2, sharing significant sequence similarity with yeast chitin synthases I and II (C. E. Bulawa (1992), Mol. Cell. Biol. 12, 1764-1776), complemented our mutant and was shown to correspond to the chromosomal locus of dit101. Thus, the mutations dit101 and csd2 (and probably also call; M. H. Valdivieso et al., (1991), J. Cell Biol. 114, 101-109) were shown to be allelic. The gene was mapped to chromosome II and was located about 3 kb distal of GAL1. Using this DNA clone, a transcript of about 3500-4000 nucleotides was detected. Comparing RNA isolated from vegetative cells and from sporulating cells at different times throughout the sporulation process, no significant differences in DIT101 transcript levels could be detected indicating absence of sporulation-specific transcriptional regulation. However, the amount of DIT101 transcript changed significantly at different stages of the mitotic cell cycle, peaking after septum formation, but before cytokinesis. As most of the chitin synthesis of vegetative cells occurs at this stage of the cell division cycle, chitin synthesis mediated by DIT101 could be primarily regulated at the level of transcription in vegetatively growing cells.