Leveraging a mouse model of mesenchymal glioblastoma (NPcis), characterized by Nf1 and Trp53 loss, we show that shRNA-mediated Abcg1 knockdown increases ER stress-induced apoptosis in vitro as well as improves the survival of immunocompetent mice with glioblastoma in vivo. This evidence concerns the gene TP53 and glioblastoma.