by Keyword: Pilocytic astrocytoma

Selt, F, Sigaud, R, Valinciute, G, Sievers, P, Zaman, J, Alcon, C, Schmid, S, Peterziel, H, Tsai, JW, Guiho, R, Martinez-Barbera, JP, Pusch, S, Deng, J, Zhai, YF, van Tilburg, CM, Schuhman, MU, Damaty, AEL, Bandopadhayay, P, Herold-Mende, C, von Deimling, A, Pfister, SM, Montero, J, Capper, D, Oehme, I, Sahm, F, Jones, DTW, Witt, O, Milde, T, (2023). BH3 mimetics targeting BCL-XL impact the senescent compartment of pilocytic astrocytoma Neuro-Oncology 25, 735-747

Background Pilocytic astrocytoma (PA) is the most common pediatric brain tumor and a mitogen-activated protein kinase (MAPK)-driven disease. Oncogenic MAPK-signaling drives the majority of cells into oncogene-induced senescence (OIS). While OIS induces resistance to antiproliferative therapies, it represents a potential vulnerability exploitable by senolytic agents. Methods We established new patient-derived PA cell lines that preserve molecular features of the primary tumors and can be studied in OIS and proliferation depending on expression or repression of the SV40 large T antigen. We determined expression of anti-apoptotic BCL-2 members in these models and primary PA. Dependence of senescent PA cells on anti-apoptotic BCL-2 members was investigated using a comprehensive set of BH3 mimetics. Results Senescent PA cells upregulate BCL-XL upon senescence induction and show dependency on BCL-XL for survival. BH3 mimetics with high affinity for BCL-XL (BCL-XLi) reduce metabolic activity and induce mitochondrial apoptosis in senescent PA cells at nano-molar concentrations. In contrast, BH3 mimetics without BCL-XLi activity, conventional chemotherapy, and MEK inhibitors show no effect. Conclusions Our data demonstrate that BCL-XL is critical for survival of senescent PA tumor cells and provides proof-of-principle for the use of clinically available BCL-XL-dependent senolytics.

JTD Keywords: bcl-xl, bh3 mimetics, oncogene-induced senescence, Bcl-xl, Bh3 mimetics, Expression, Family, Inhibitor, Low-grade glioma, Navitoclax, Oncogene-induced senescence, Pilocytic astrocytoma, Stem-cells