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Vos, H.

Publications and source records attributed to Vos, H..

3 recordsLinked to original sources

Hsa-miR-31-5p controls a metabolic switch in psoriatic keratinocytes that identifies therapeutic intervention

Psoriasis is characterized by a combination of keratinocyte hyperproliferation and immune cell activation. Immune cell activation requires increased glucose consumption, consequently limiting glucose availability for other cell types like keratinocytes. In psoriasis Hsa-microRNA-31-5p (miR-31) is highly expressed in keratinocytes. Here we show that miR-31 expression in keratinocytes is induced by limited glucose availability and increases survival under limiting glucose conditions, by increasing glutamine metabolism. In addition, miR-31 induced glutamine metabolism results in secretion of specific metabolites (aspartate and glutamate) but also immuno-modulatory factors. We show that this miR-31-induced secretory phenotype is sufficient to induce Th17 cell differentiation, a hallmark of psoriasis. Inhibition of glutaminase (GLS) using CB-839 impedes miR31-induced metabolic rewiring and secretion of immuno-modulatory factors. Concordantly, pharmacological targeting of GLS alleviated psoriasis pathology in a mouse model of psoriasis. Together our data illustrate an emerging concept of metabolic interaction across cell compartments that characterizes disease development, which can be employed to design effective treatment options for disease, as shown here for psoriasis.

immunology↗

A Pan-Cancer Blueprint of the Heterogeneous Tumour Microenvironment Revealed by Single-Cell Profiling

AO_SCPLOWBSTRACTC_SCPLOWThe stromal compartment of the tumour microenvironment consists of a heterogeneous set of tissue-resident and tumour-infiltrating cells, which are profoundly moulded by cancer cells. An outstanding question is to what extent this heterogeneity is similar between cancers affecting different organs. Here, we profile 233,591 single cells from patients with lung, colorectal, ovary and breast cancer (n=36) and construct a pan-cancer blueprint of stromal cell heterogeneity using different single-cell RNA and protein-based technologies. We identify 68 stromal cell populations, of which 46 are shared between cancer types and 22 are unique. We also characterise each population phenotypically by highlighting its marker genes, transcription factors, metabolic activities and tissue-specific expression differences. Resident cell types are characterised by substantial tissue specificity, while tumour-infiltrating cell types are largely shared across cancer types. Finally, by applying the blueprint to melanoma tumours treated with checkpoint immunotherapy and identifying a naive CD4+ T-cell phenotype predictive of response to checkpoint immunotherapy, we illustrate how it can serve as a guide to interpret scRNA-seq data. In conclusion, by providing a comprehensive blueprint through an interactive web server, we generate a first panoramic view on the shared complexity of stromal cells in different cancers.

cancer biology↗

Cysteine oxidation triggers amyloid fibril formation of the tumor suppressor p16INK4A

Accumulation of the CDK4/6 inhibitor p16INK4A in response to oncogenic transformation leads to cell cycle arrest and senescence and is therefore frequently lost in cancer. p16INK4A is also known to accumulate under conditions of oxidative stress and thus could potentially be regulated by the reversible oxidation of cysteines (redox signaling). Indeed, oxidation of the single cysteine in p16INK4A in human cells occurs under relatively mild oxidizing conditions and leads to disulfide-dependent dimerization. p16INK4A is an all alpha-helical protein, but here we report that upon cysteine-dependent dimerization, p16INK4A undergoes a dramatic structural rearrangement and forms aggregates that have the typical features of amyloid fibrils, including binding of diagnostic dyes, presence of cross-{beta} sheet structure, and typical dimensions found in electron microscopy. p16INK4A amyloid formation abolishes its function as a CDK4/6 inhibitor. Collectively, these observations mechanistically link the cellular redox state to the inactivation of p16INK4A through the formation of amyloid fibrils.

biochemistry↗