Metabolic homeostasis is essential for cellular function in living organisms. In cancer cells, metabolic processes are reprogrammed to meet the energy demands and biosynthetic needs for rapid growth. This reprogramming enhances nutrient flux through the glycolytic pathway, supporting ATP production and branching into pathways that synthesize macromolecules required for cell proliferation. One critical branching pathway is the hexosamine biosynthesis pathway (HBP), which, driven by metabolic reprogramming, facilitates the synthesis of uridine-5'-diphospho-N-acetylglucosamine (UDP-GlcNAc), a glycosylation substrate. This pathway is regulated by the rate-limiting enzyme glutamine-fructose-6-phosphate transaminase (GFPT), a key controller of cellular UDP-GlcNAc levels and protein glycosylation. Dysregulation of GFPT is linked to metabolic disorders, like in diabetes, and it is also frequently upregulated in cancers. Given that GFPT plays a pivotal role in cancer metabolism, elucidating its regulatory interactions with other metabolic signaling pathways under metabolic stress is crucial to identifying therapeutic vulnerabilities in cancer. This review discusses the interaction network of GFPT with other metabolic pathways, its role in nutrient sensing, and the implications of GFPT deregulation in cancer.