Cytosolic GPT1 and mitochondrial GPT2 generate both α-KG and alanine for protein synthesis (164), among them GPT2 is particularly critical in KRAS-driven CRC, breast cancer, and glioblastoma, as it sustains mitochondrial metabolic homeostasis and fuels anabolic metabolism to support the aggressive proliferation of KRAS-mutant tumor cells (153). Here, KRAS is linked to glioblastoma.