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Biology subjects

McCloy, R.

Publications and source records attributed to McCloy, R..

2 recordsLinked to original sources

Adult-type diffuse gliomas share recurring cell states driven by a common astrocyte-like glioma stem cell population

Adult-type diffuse gliomas are a family of aggressive brain tumours with few effective treatments. Their complex cellular makeup adds to the challenge of finding successful therapies. This intratumoural heterogeneity is fuelled by a subpopulation of glioma stem-like cells (GSCs) that drive tumour growth and resistance to standard treatments. Previous research focused on the three glioma types (astrocytoma, oligodendroglioma, glioblastoma) individually revealed malignant cells mimic the transcriptional profiles of normal brain cell types. Whether these diverse cellular states stem from a shared biological origin is unknown. Here, we show through single-cell RNA sequencing of 40 glioma tumours that all gliomas are described by seven recurring cell states. We also identify a shared astrocyte-like GSC population. Our unique method of identifying GSCs, based on reconstructed tumour phylogenies, repositions astrocyte-like cells at the apex of a differentiation hierarchy in glioma. Our findings indicate the transcriptional heterogeneity observed in gliomas stems from a GSC population recapitulating lineages of healthy adult neural stem cells. These results suggest a shared lineage drives the intratumoural heterogeneity observed in adult-type diffuse gliomas. We anticipate that a deeper understanding of the molecular mechanisms maintaining the GSC state will provide a new framework for future therapeutic development and research into glioma cell biology. HighlightsO_LIRecurring cell states are shared across adult-type diffuse gliomas C_LIO_LIReconstructed tumour phylogenies identify an astrocyte-like glioma stem cell population C_LIO_LITumour subclones are segregated non-randomly across cell states C_LI

cancer biology↗

The E3 ubiquitin ligase UBR5 regulates centriolar satellite stability and primary cilia formation via ubiquitylation of CSPP-L.

Primary cilia are crucial for signal transduction in a variety of pathways, including Hedgehog and Wnt. Disruption of primary cilia formation (ciliogenesis) is linked to numerous developmental disorders (known as ciliopathies) and diseases, including cancer. The Ubiquitin-Proteasome System (UPS) component UBR5 was previously identified as a putative modulator of ciliogenesis in a functional genomics screen. UBR5 is an E3 Ubiquitin ligase that is frequently deregulated in tumours, but its biological role in cancer is largely uncharacterised, partly due to a lack of understanding of interacting proteins and pathways. We validated the effect of UBR5 depletion on primary cilia formation using a robust model of ciliogenesis, and identified CSPP1, a centrosomal and ciliary protein required for cilia formation, as a UBR5-interacting protein. We show that UBR5 ubiquitylates CSPP1, and that UBR5 is required for cytoplasmic organization of CSPP1-comprising centriolar satellites in centrosomal periphery. Hence, we have established a key role for UBR5 in ciliogenesis that may have important implications in understanding cancer pathophysiology.

cell biology↗