IGF1 and central nervous system cancer: 88). This was because of a rewiring of the CRC cell metabolism to higher glutamine consumption in an IGFR-dependent manner. Subsequent investigation in orthotopic models demonstrated a reduced formation of metastases when IGF1 was neutralised following RT (Ref. 88). These results corroborate data from a murine glioma study which established a radioprotective role for IGFR1 ex vivo and showed blockade of IGFR1 increased the sensitivity of glioma stem cells to radiation (Ref. 89).