Research Paper Volume 13, Issue 14 pp 18106—18130
Autophagy inhibition reinforces stemness together with exit from dormancy of polydisperse glioblastoma stem cells
- 1 EA 3842 CAPTuR, GEIST Institute, University of Limoges, Limoges 87025, Cedex France
- 2 Experimental Neurosurgery, Neuroscience Center, Goethe University Hospital, Frankfurt am Main D-60590, Germany
- 3 German Cancer Consortium (D.K.T.K.), Partner Site Frankfurt, Frankfurt am Main D-60590, Germany
- 4 Service d’Oncologie, CHU, Limoges 87025, France
Received: January 20, 2021 Accepted: July 9, 2021 Published: July 27, 2021https://doi.org/10.18632/aging.203362
How to Cite
Copyright: © 2021 Brunel et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Therapeutic resistance and infiltrative capacities justify the aggressiveness of glioblastoma. This is due to cellular heterogeneity, especially the presence of stemness-related cells, i.e. Cancer Stem Cells (CSC). Previous studies focused on autophagy and its role in CSCs maintenance; these studies gave conflicting results as they reported either sustaining or disruptive effects. In the present work, we silenced two autophagy related genes -either Beclin1 or ATG5- by shRNA and we explored the ensuing consequences on CSCs markers’ expression and functionalities. Our results showed that the down regulation of autophagy led to enhancement in expression of CSCs markers, while proliferation and clonogenicity were boosted. Temozolomide (TMZ) treatment failed to induce apoptotic death in shBeclin1-transfected cells, contrary to control. We optimized the cellular subset analysis with the use of Sedimentation Field Flow Fractionation, a biological event monitoring- and cell sorting-dedicated technique. Fractograms of both shBeclin1 and shATG5 cells exhibited a shift of elution peak as compared with control cells, showing cellular dispersion and intrinsic sub-fraction modifications. The classical stemness fraction (i.e. F3) highlighted data obtained with the overall cellular population, exhibiting enhancement of stemness markers and escape from dormancy. Our results contributed to illustrate CSCs polydispersity and to show how these cells develop capacity to bypass autophagy inhibition, thanks to their acute adaptability and plasticity.