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Biology subjects

Mangoli, A.

Publications and source records attributed to Mangoli, A..

2 recordsLinked to original sources

Ataxia-telangiectasia mutated (Atm) disruption sensitizes spatially-directed H3.3K27M/TP53 diffuse midline gliomas to radiation therapy

Diffuse midline gliomas (DMGs) are lethal brain tumors characterized by p53-inactivating mutations and oncohistone H3.3K27M mutations that rewire the cellular response to genotoxic stress, which presents therapeutic opportunities. We used RCAS/tv-a retroviruses and Cre recombinase to inactivate p53 and induce K27M in the native H3f3a allele in a lineage- and spatially-directed manner, yielding primary mouse DMGs. Genetic or pharmacologic disruption of the DNA damage response kinase Ataxia-telangiectasia mutated (ATM) enhanced the efficacy of focal brain irradiation, extending mouse survival. This finding suggests that targeting ATM will enhance the efficacy of radiation therapy for p53-mutant DMG but not p53-wildtype DMG. We used spatial in situ transcriptomics and an allelic series of primary murine DMG models with different p53 mutations to identify transactivation-independent p53 activity as a key mediator of such radiosensitivity. These studies deeply profile a genetically faithful and versatile model of a lethal brain tumor to identify resistance mechanisms for a therapeutic strategy currently in clinical trials.

cancer biology↗

Interplay between ATRX and IDH1 mutations governs innate immune responses in diffuse gliomas

Stimulating the innate immune system has been explored as a therapeutic option for the treatment of gliomas. Inactivating mutations in ATRX, defining molecular alterations in IDH-mutant astrocytomas, have been implicated in dysfunctional immune signaling. However, little is known about the interplay between ATRX loss and IDH mutation on innate immunity. To explore this, we generated ATRX knockout glioma models in the presence and absence of the IDH1R132H mutation. ATRX-deficient glioma cells were sensitive to dsRNA-based innate immune agonism and exhibited impaired lethality and increased T-cell infiltration in vivo. However, the presence of IDH1R132Hdampened baseline expression of key innate immune genes and cytokines in a manner restored by genetic and pharmacological IDH1R132H inhibition. IDH1R132H co-expression did not interfere with the ATRX KO-mediated sensitivity to dsRNA. Thus, ATRX loss primes cells for recognition of dsRNA, while IDH1R132H reversibly masks this priming. This work reveals innate immunity as a therapeutic vulnerability of astrocytoma.

cancer biology↗