Fueling Prostate Cancer: The Central Role of Glutamine/Glutamate Metabolic Reprogramming

Metabolic reprogramming induced by the glutamine/glutamate (Gln/Glu) metabolic pathway is a key mechanism in ATP production, precursor biosynthesis, and redox homeostasis, promoting prostate cancer (PCa) growth and proliferation. This evolutionarily acquired hallmark of cancers enables malignant cells to adapt their bioenergetic and biosynthetic pathways in response to microenvironmental stresses. Therefore, Gln/Glu metabolism orchestrates epigenetic regulation, metastatic capacity, and oxidative homeostasis in PCa, supporting the survival of PCa tumors. Fluctuations in Glu metabolite levels and oxygen tension shape the PCa epigenome by facilitating Glu-derived α-ketoglutarate (α-KG) activation of TET and KDM enzymes, which drive histone and DNA demethylation. Furthermore, tumor progression toward metastatic castration-resistant PCa is characterized by heightened Gln/Glu dependency and increased Gln uptake. Within the tumor microenvironment (TME), a dynamic tug-of-war occurs between tumor and immune cells, competing for Gln metabolites. Gln/Glu converges on critical oncogenic signaling axes, including NF-κB/Nrf2, c-Myc/androgen receptor, MAPK/ERK, and PI3K/AKT/mTOR. Additionally, extracellular Glu release via SLC7A11 and PSMA triggers metabotropic glutamate receptor (mGluR) signaling, further potentiating oncogenic programs. Targeting this Gln/Glu metabolic network thus presents a promising therapeutic approach against PCa. In this review, we summarize the role of Gln/Glu in PCa progression based on the compartmentalization of the Gln/Glu metabolic pathway to elucidate why PCa cells manifest dependence on Gln/Glu. Eventually, we highlight potential therapeutic targets that can be exploited for PCa treatment.