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Aggressive tumours are defined by microenvironmental stress adaptation and metabolic reprogramming. Within this niche, lipid droplet accumulation has emerged as a key strategy to buffer toxic lipids and suppress ferroptosis. Lipid droplet formation can occur via de novo lipogenesis or extracellular lipid-scavenging. However, how tumour cells coordinate these processes remains poorly understood. Here we identify a chondroitin sulfate (CS)-enriched glycocalyx as a hallmark of the acidic microenvironment in glioblastoma and central nervous system metastases. This CS-rich glycocalyx encapsulates tumour cells, limits lipid particle uptake and protects against lipid-induced ferroptosis. Mechanistically, we demonstrate that converging hypoxia-inducible factor and transforming growth factor beta signalling induces a glycan switch on syndecan-1—replacing heparan sulfate with CS—thereby impairing its lipid-scavenging function. Dual inhibition of CS biosynthesis and diacylglycerol O-acyltransferase-1, a critical enzyme in lipid droplet formation, triggers catastrophic lipid peroxidation and ferroptotic cell death. These findings define glycan remodelling as a core determinant of metabolic plasticity, positioning the dynamic glycocalyx as a master regulator of nutrient access, ferroptotic sensitivity and therapeutic vulnerability in cancer.

Metabolic dysfunction–associated steatotic liver disease (MASLD) is the most common chronic liver disease worldwide for which there is only one approved treatment. Adenosine monophosphate–activated protein kinase (AMPK) is an interesting therapeutic target since it acts as a central regulator of cellular metabolism. Despite efforts to target AMPK, no direct activators have yet been approved for treatment of this disease. This study investigated the effect of the AMPK activator ATX-304 in a preclinical mouse model of progressive fatty liver disease. The data demonstrated that ATX-304 diminishes body fat mass, lowers blood cholesterol levels, and mitigates general liver steatosis and the development of liver fibrosis, but with pronounced local heterogeneities. The beneficial effects of ATX-304 treatment were accompanied by a shift in the liver metabolic program, including increased fatty acid oxidation, reduced lipid synthesis, as well as remodeling of cholesterol and lipid transport. We also observed variations in lipid distribution among liver lobes in response to ATX-304, and a shift in the zonal distribution of lipid droplets upon treatment. Taken together, our data suggested that ATX-304 holds promise as a potential treatment for MASLD.

Neuron–glioma interactions are critical drivers of glioma progression, with neuronal activity promoting tumor growth and invasion through paracrine signaling and direct synaptic input. Beyond well-established glutamatergic synapses, recent discoveries revealed that GABAergic interactions also contribute to glioma proliferation. Here, we focus on how glioma cells decode neuronal cues via epigenetic mechanisms, including enhancer reprogramming, chromatin remodeling, and rewiring of 3D genome organization, with transcriptions factors such as SMAD3 and PITX1 orchestrating transcriptional programs that sustain neuron-to-glioma communication. Additionally, recent integration of multi-omics data highlights gene regulatory networks linked to GABAergic signaling as contributors to glioblastoma (GB) pathogenesis. We also underscore the distinct roles of GABAergic signaling across glioma subtypes, noting that, in GB, GABA-related metabolic and paracrine mechanisms, rather than synaptic input, may drive tumor progression. Understanding how epigenetic reprogramming facilitates glioma integration into neural circuits opens new avenues to disrupt these malignant neuron–glioma interactions by targeting the epigenetic machinery.

Wnt signaling plays a pivotal role during development and homeostasis. Upon pathway activation, CTNNB1 (also known as beta-catenin) drives the expression of target genes from regulatory regions bound by TCF/LEF transcription factors. Gene regulation, however, entails the interplay between sequence information and 3D genome structure, yet the impact of Wnt signaling on genome structure has been poorly explored. Here, we investigate how Wnt signaling influences CTCF and cohesin, key regulators of 3D genome organization. We identify a series of novel CTCF binding sites that emerge upon Wnt stimulation: CTCF Redistributions Under Wnt (RUW). RUW sites are characterized by CTCF, cohesin, and TCF/LEF occupancy, and are dependent on beta-catenin. Beta-catenin and CTCF colocalize upon pathway activation, and disruption of selected binding sites perturbs target gene regulation. Moreover, Wnt signaling reorganizes the 3D genome as evidenced by genome-wide alterations in CTCF-bound loops. This work reveals a previously unexplored role for CTCF in the regulation of Wnt signaling.

In muscular dystrophies, muscle fibers loose integrity and die, causing significant suffering and premature death. Strikingly, the extraocular muscles (EOMs) are spared, functioning well despite the disease progression. Although EOMs have been shown to differ from body musculature, the mechanisms underlying this inherent resistance to muscle dystrophies remain unknown. Here, we demonstrate important differences in gene expression as a response to muscle dystrophies between the EOMs and trunk muscles in zebrafish via transcriptomic profiling. We show that the LIM-protein Fhl2 is increased in response to the knockout of desmin, plectin and obscurin, cytoskeletal proteins whose knockout causes different muscle dystrophies, and contributes to disease protection of the EOMs. Moreover, we show that ectopic expression of fhl2b can partially rescue the muscle phenotype in the zebrafish Duchenne muscular dystrophy model sapje, significantly improving their survival. Therefore, Fhl2 is a protective agent and a candidate target gene for therapy of muscular dystrophies.

A first-in-human trial demonstrated that a vaccine targeting the histone mutation H3K27M can induce an immune response, in a mutation-specific manner, in patients with diffuse midline glioma. In a recent study by Boschert et al., the same group now dissects the functional immune response triggered after effective vaccination of one of the patients, who has been in remission for over 3 years. The H3K27M peptide vaccine, named H3-vac, induces a CD4⁺ T-cell-specific immune response in this patient and expands the repertoire of polyclonal H3K27M-specific T-cell receptors. A clonal H3K27M-reactive B-cell population was also detected in the patient's cerebrospinal fluid. Importantly, the immune response is induced across various human leukocyte antigen alleleotypes, indicating the potential efficacy of the vaccine in diverse populations. By exploring in detail the immune response linked to this patient's long-term survival, the authors prove peptide vaccinations as a viable therapeutic approach. This paves the way for personalised therapies harnessing immunogenic T- and B-cell responses against different tumour types.

Several preclinical models have been recently developed for metabolic associated fatty liver disease (MAFLD) and associated hepatocellular carcinoma (HCC) but comprehensive analysis of the regulatory and transcriptional landscapes underlying disease in these models are still missing. We investigated the regulatory and transcriptional landscape in fatty livers and liver tumours from DIAMOND mice that faithfully mimic human HCC development in the context of MAFLD. RNA-sequencing and ChIP-sequencing revealed rewiring of the Wnt/β-catenin regulatory network in DIAMOND tumours, as manifested by chromatin remodelling and associated switching in the expression of the canonical TCF/LEF downstream effectors. We identified splicing as a major mechanism leading to constitutive oncogenic activation of β-catenin in a large subset of DIAMOND tumours, a mechanism that is independent on somatic mutations in the locus and that has not been previously shown. Similar splicing events were found in a fraction of human HCC and hepatoblastoma samples.

Background: Glioblastoma (GB) is the most aggressive of all primary brain tumours and due to its highly invasive nature, surgical resection is nearly impossible. Patients typically rely on radiotherapy with concurrent temozolomide (TMZ) treatment and face a median survival of ~ 14 months. Alterations in the Epidermal Growth Factor Receptor gene (EGFR) are common in GB tumours, but therapies targeting EGFR have not shown significant clinical efficacy.

Methods: Here, we investigated the influence of the EGFR regulatory genome on GB cells and identified novel EGFR enhancers located near the GB-associated SNP rs723527. We used CRISPR/Cas9-based approaches to target the EGFR enhancer regions, generating multiple modified GB cell lines, which enabled us to study the functional response to enhancer perturbation.

Results: Epigenomic perturbation of the EGFR regulatory region decreases EGFR expression and reduces the proliferative and invasive capacity of glioblastoma cells, which also undergo a metabolic reprogramming in favour of mitochondrial respiration and present increased apoptosis. Moreover, EGFR enhancer-perturbation increases the sensitivity of GB cells to TMZ, the first-choice chemotherapeutic agent to treat glioblastoma.

Conclusions: Our findings demonstrate how epigenomic perturbation of EGFR enhancers can ameliorate the aggressiveness of glioblastoma cells and enhance the efficacy of TMZ treatment. This study demonstrates how CRISPR/Cas9-based perturbation of enhancers can be used to modulate the expression of key cancer genes, which can help improve the effectiveness of existing cancer treatments and potentially the prognosis of difficult-to-treat cancers such as glioblastoma.

Chromatin organization controls transcription by modulating 3D-interactions between enhancers and promoters in the nucleus. Alterations in epigenetic states and 3D-chromatin organization result in gene expression changes contributing to cancer. Here, we map the promoter-enhancer interactome and regulatory landscape of glioblastoma, the most aggressive primary brain tumour. Our data reveals profound rewiring of promoter-enhancer interactions, chromatin accessibility and redistribution of histone marks in glioblastoma. This leads to loss of long-range regulatory interactions and overall activation of promoters, which orchestrate changes in the expression of genes associated to glutamatergic synapses, axon guidance, axonogenesis and chromatin remodelling. SMAD3 and PITX1 emerge as major transcription factors controlling genes related to synapse organization and axon guidance. Inhibition of SMAD3 and neuronal activity stimulation cooperate to promote proliferation of glioblastoma cells in co-culture with glutamatergic neurons, and in mice bearing patient-derived xenografts. Our findings provide mechanistic insight into the regulatory networks that mediate neurogliomal synaptic communication.

Genome architecture, epigenetics and enhancer function control the fate and identity of cells. Reprogramming to induced pluripotent stem cells (iPSCs) changes the transcriptional profile and chromatin landscape of the starting somatic cell to that of the pluripotent cell in a stepwise manner. Changes in the regulatory networks are tightly regulated during normal embryonic development to determine cell fate, and similarly need to function in cell fate control during reprogramming. Switching off the somatic program and turning on the pluripotent program involves a dynamic reorganization of the epigenetic landscape, enhancer function, chromatin accessibility and 3D chromatin topology. Within this context, we will review here the current knowledge on the processes that control the establishment and maintenance of pluripotency during somatic cell reprogramming.