Search

Poor survival and lack of treatment response in glioblastoma (GBM) is attributed to the persistence of glioma stem cells (GSCs). To identify novel therapeutic approaches, we performed CRISPR/Cas9 knockout screens and discovered TGFβ activated kinase (TAK1) as a selective survival factor in a significant fraction of GSCs. Loss of TAK1 kinase activity results in RIPK1-dependent apoptosis via Caspase-8/FADD complex activation, dependent on autocrine TNFα ligand production and constitutive TNFR signaling. We identify a transcriptional signature associated with immune activation and the mesenchymal GBM subtype to be a characteristic of cancer cells sensitive to TAK1 perturbation and employ this signature to accurately predict sensitivity to the TAK1 kinase inhibitor HS-276. In addition, exposure to pro-inflammatory cytokines IFNγ and TNFα can sensitize resistant GSCs to TAK1 inhibition. Our findings reveal dependency on TAK1 kinase activity as a novel vulnerability in immune-activated cancers, including mesenchymal GBMs that can be exploited therapeutically., (© 2024. The Author(s).)

Background: A potentially fatal complication of sepsis is septic acute kidney injury. Stem cell therapy is a potential new method of treating sepsis and has been applied to treat some human diseases., Objectives: This study investigated the effects of secretome-MSCs on NGAL, CRP, NF-κB, and MMP-9 proteins, and histopathology in mice with septic AKI., Methods: A post-test-only group design was conducted in 30 Balb/C male mice, which were randomly assigned to five groups: the control group was intraperitoneally injected with 0.5 ml of 0.9 % NaCl, the septic AKI, and the treatment groups (T1, T2, and T3) were intraperitoneally injected with 0.5 ml of 0.9 % NaCl and 0.3 mg/kg BW LPS single dose for three days. Three-day treatments of 150, 300, and 600 µl secretome-MSCs were administered intraperitoneally into the treatment groups. Furthermore, kidney and blood samples were collected for biochemical and histopathological analyses., Results: The T1, T2, and T3 groups had lower expression of NF-κB and MMP-9 and significantly lower CRP and NGAL levels than that of septic AKI group. T1 (1.21 ± 0.19), T2 (0.75 ± 0.22), and T3 (0.38 ± 0.14) groups demonstrated lower average scores for inflammation, necrosis, hemorrhage, and degeneration compared to septic AKI group (2.17 ± 0.13)., Conclusions: Administration of 600 µl/20 g BW secretome-MSCs suppresses NF-κB and MMP-9 expression and reduces CRP and NGAL levels. Meanwhile, the 150 and 300 µl/20 g BW doses also indicated a greater improvement in renal tissue damage of mice with septic AKI., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author(s).)

Posttranslational modifications of histones (PTMs) are associated with specific chromatin and gene expression states 1,2 . Although studies in Drosophila melanogaster have revealed phenotypic associations between chromatin-modifying enzymes and their histone substrates, comparable studies in mammalian models do not exist 3-5 . Here, we use CRISPR base editing in mouse embryonic stem cells (mESCs) to address the regulatory role of lysine 27 of histone H3 (H3K27), a substrate for Polycomb repressive complex 2 (PRC2)-mediated methylation and CBP/EP300-mediated acetylation 6,7 . By generating pan-H3K27R (pK27R) mutant mESCs, where all 28 alleles of H3.1, H3.2 and H3.3 have been mutated, we demonstrate similarity in transcription patterns of genes and differentiation to PRC2-null mutants. Moreover, H3K27 acetylation is not essential for gene derepression linked to loss of H3K27 methylation, or de novo activation of genes during cell-fate transition to epiblast-like cells (EpiLCs). In conclusion, our results show that H3K27 is an essential substrate for PRC2 in mESCs, whereas other PTMs in addition to H3K27 acetylation are likely involved in mediating CBP/EP300 function. Our work demonstrates the feasibility of large-scale multicopy gene editing to interrogate histone PTM function in mammalian cells., (© 2022. The Author(s), under exclusive licence to Springer Nature America, Inc.)