The process of hepatocarcinogenesis in the diethylnitrosamine (DEN) initiation/phenobarbital (PB) promotion mouse model involves the selective clonal outgrowth of cells harboring oncogene mutations in Ha-ras, B-raf, or Ctnnb1. Here, we have characterized mouse liver tumors harboring either Ctnnb1 or Ha-ras mutations via integrated molecular profiling at the transcriptional and translational and post-translational levels. In addition, metabolites of the intermediary metabolism were quantified by high resultion 1H magic angle nuclear magnetic resonance (HR-MAS NMR). We have identified tumor characteristic genotype-specific differences in mRNA and miRNA expression, protein levels, and post-translational modifications and in metabolite levels that facilitate the molecular and biochemical stratification of tumor phenotypes. Bioinformatic integration of these data at the pathway level led to novel insights into tumor genotype-specific aberrant cell signaling and in particular to a better understanding of alterations in pathways of the cell intermediary metabolism, which are driven by the constitutive activation of the -Catenin and Ha-ras oncoproteins in tumors of the two genotypes.
Ha-ras and β-catenin oncoproteins orchestrate metabolic programs in mouse liver tumors.
Sex, Specimen part
View SamplesAutophagy selectively degrades aggregation-prone misfolded proteins caused by defective cellular proteostasis. However, the complexity of autophagy may prevent the full appreciation of how its modulation could be used as a therapeutic strategy in disease management. Here we define a molecular pathway through which recombinant interleukin-1 receptor antagonist (IL-1Ra, anakinra) affects cellular proteostasis independently from the IL-1 receptor (IL-1R1). Anakinra promoted H2O2-driven autophagy through a xenobiotic sensing pathway involving the aryl hydrocarbon receptor that, activated through the indoleamine 2,3-dioxygenase 1-kynurenine pathway, transcriptionally activates NADPH Oxidase 4 independent of the IL-1R1. By coupling the mitochondrial redox balance to autophagy, anakinra improved the dysregulated proteostasis network in murine and human cystic fibrosis. We anticipate that anakinra may represent a therapeutic option in addition to its IL-1R1 dependent anti-inflammatory properties by acting at the intersection of mitochondrial oxidative stress and autophagy with the capacity to restore conditions in which defective proteostasis leads to human disease. Overall design: mRNA profiles of alveolar macrophages purified from C57BL/6 and Il1r1-/- mice treated or not with Anakinra
Anakinra restores cellular proteostasis by coupling mitochondrial redox balance to autophagy.
Specimen part, Genotype, Subject
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