FGFR1 inhibition improves therapy efficacy and prevents metabolic adaptation associated with temozolomide resistance in glioblastoma

Recurrent therapy resistance is a major limitation in clinical efficacy and for the outcome of glioblastoma (GBM) patients, positioning GBM among the tumor types with the poorest survival outcomes. In this work, we dissected resistance mechanisms in GBM, which resulted in the identification of FGFR1 pathway as a major regulator of the signaling and metabolic rewiring associated with temozolomide (TMZ) resistance in GBM. Hence, we described a mechanism of resistance that operates at two major levels. First, a p53-mediated regulation of cell cycle inducing cell cycle arrest to allow DNA repair in response to TMZ. And second, a complete metabolic rewiring promoting lipid catabolism and preventing lipid peroxidation. Both the p53-mediated response and the metabolic adaptation are controlled by FGFR1, as inhibition of the FGFR1 pathway completely abolishes this signaling and metabolic reprograming, restoring sensitivity to TMZ. Our results also indicated a correlation of FGFR1 levels with poor prognosis in GBM patients, and validated the treatment of TMZ in combination with FGFR1 inhibitors as an efficient strategy to induce tumor cell death in pre-clinical animal models. This data position the receptor FGFR1 as a very promising candidate for evaluation in future clinical approaches to limit the development of therapy resistance to TMZ in GBM patients.