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P120-catenin dependent glioma-cell networks drive growth and diffuse brain infiltration

ABSTRACT: The poor prognosis of diffuse gliomas is the consequence of adaptive growth and survival programs coupled to their unsurmountable capacity to infiltrate the brain. Diffuse brain infiltration is a particularly detrimental hallmark of gliomas, however the underlying cellular and signaling mechanisms remain elusive. Histological analysis of glioma samples suggests brain invasion by individual glioma cells extending along blood vessels and nerve tracts, consistent with individual-cell growth and invasion programs. However, using thick 3D tissue sections, we here show that human diffuse gliomas consist of multicellular networks in both tumor center and invasion region. This was confirmed in three orthotopic human glioma xenograft models in mouse brain reflecting neuronal, proneural and mesenchymal subtypes. The connections between glioma cells are provided by either branched filamentous protrusions connecting cells across distance or epithelial-like linear adherens junctions between directly adjacent cells. These intercellular contacts showed dynamic turn-over kinetics, which enabled intercellularly synchronized calcium signaling waves, directionally persistent migration as network and network plasticity. Interference with the stability of adherens junction by downregulating p120-catenin causes irreversibly compromised cell-cell interaction, near-complete inhibition of diffuse brain infiltration and a severe growth defect and marginalized microlesions as outcome. Mining of human glioma cohorts revealed an inverse association of p120 with patient survival and, using next-generation RNA sequencing, profound cell reprogramming with perturbed cell adhesion and axonal guidance pathways was uncovered after p120 downregulation. In conclusion, reminiscent of neuronal and glial progenitor programs during morphogenesis and repair, diffuse gliomas progress as neuronal-like, collective network the subunits of which cooperate by complex cell-cell signaling to promote cell growth and detrimental brain infiltration. Targeting adherens junctions and cell-cell cooperation thus represent unanticipated therapeutic principles to prevent glioma progression.

ORGANISM(S): Homo sapiens

PROVIDER: GSE73999 | GEO | 2019/12/02

REPOSITORIES: GEO

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P120-catenin dependent glioma-cell networks drive growth and diffuse brain infiltration

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