ATRX loss in glioma results in dysregulation of cell-cycle phase transition and ATM inhibitor radio-sensitization

ATRX, a chromatin remodeler protein, is recurrently mutated in H3F3A-mutant pediatric glioblastoma (GBM) and isocitrate dehydrogenase (IDH)-mutant grade 2/3 adult glioma. Previous work has shown that ATRX-deficient GBM cells show enhanced sensitivity to irradiation, but the etiology remains unclear. We find that ATRX binds the regulatory elements of cell-cycle phase transition genes in GBM cells, and there is a marked reduction in Checkpoint Kinase 1 (CHEK1) expression with ATRX loss, leading to the early release of G2/M entry after irradiation. ATRX-deficient cells exhibit enhanced activation of master cell-cycle regulator ATM with irradiation. Addition of the ATM inhibitor AZD0156 doubles median survival in mice intracranially implanted with ATRX-deficient GBM cells, which is not seen in ATRX-wild-type controls. This study demonstrates that ATRX-deficient high-grade gliomas (HGGs) display Chk1-mediated dysregulation of cell-cycle phase transitions, which opens a window for therapies targeting this phenotype.

Related Products

Cat.No. Product Name Information
S8375 AZD0156 AZD0156 is a potent and selective inhibitors of ATM kinase, with potential chemo-/radio-sensitizing and antineoplastic activities. AZD0156 prevents DNA damage checkpoint activation, disrupts DNA damage repair, induces tumor cell apoptosis, and leads to cell death of ATM-overexpressing tumor cells.

Related Targets

ATM/ATR Apoptosis related