Cationic amino acid transporter (CAT)

Cationic amino acid transporters (CATs) are a subfamily of the solute carrier family 7 (SLC7) that mediate the sodium-independent transport of basic amino acids, including L-arginine, L-lysine, and L-ornithine [4, 11]. These transporters, primarily CAT-1, CAT-2, and CAT-3, are essential for maintaining intracellular amino acid pools required for protein synthesis and the production of metabolic signaling molecules like nitric oxide (NO) and polyamines [6, 17]. In many cancers, such as chronic lymphocytic leukemia and gastric cancer, CATs are overexpressed to meet the high metabolic demands of proliferating cells, making them attractive therapeutic targets [1, 4]. Beyond oncology, CATs play significant roles in cardiovascular health by regulating NO-mediated vasodilation and in the immune response by modulating arginine availability for macrophages and T cells [11, 16]. Pharmacological targeting of CATs involves the development of small-molecule inhibitors to starve tumor cells of essential nutrients or to modulate inflammatory signaling [4, 12]. However, therapeutic intervention must account for the potential impact on systemic amino acid homeostasis and the essential role of these transporters in normal physiological processes [15, 18].

Other names

SLC7A1SLC7A2SLC7A3SLC7A4SLC7A14System y+ATRC1ATRC2ATRC3Ecotropic retroviral leukemia receptor

Competitive inhibition of cationic amino acid transport, leading to depletion of intracellular arginine and subsequent inhibition of the mTOR signaling pathway and nitric oxide production [4, 6, 11].