Organic cation transporter 2, Multidrug and toxin extrusion protein 1, and Multidrug and toxin extrusion protein 2-K (OCT2/MATE1/MATE2-K)

The OCT2/MATE1/MATE2-K transport system is a critical pathway for the renal secretion of organic cations, consisting of the Organic Cation Transporter 2 (OCT2/SLC22A2) and the Multidrug and Toxin Extrusion proteins 1 and 2-K (MATE1/SLC47A1 and MATE2-K/SLC47A2) [1, 12]. OCT2 is localized to the basolateral membrane of renal proximal tubule cells, where it facilitates the uptake of cationic drugs and endogenous metabolites from the blood into the cell [1, 8]. MATE1 and MATE2-K are expressed on the apical membrane and mediate the efflux of these substances into the tubular lumen for excretion in the urine [8, 10]. This coordinated transport is a major determinant of the pharmacokinetics and renal clearance of numerous drugs, most notably the anti-diabetic agent metformin and the chemotherapeutic cisplatin [6, 16]. Inhibition of these transporters by "perpetrator" drugs, such as cimetidine or dolutegravir, can lead to significant drug-drug interactions, increasing the systemic exposure or local tissue toxicity of "victim" drugs [2, 12]. Furthermore, the differential transport of platinum-based agents by this system explains the specific nephrotoxicity of cisplatin, which is an OCT2 substrate but a poor MATE substrate, leading to its accumulation in renal cells [6, 16]. Genetic polymorphisms in the genes encoding these transporters (SLC22A2, SLC47A1, SLC47A2) can also significantly influence drug response and toxicity profiles [4, 15]. Consequently, this pathway is a key focus of regulatory guidelines for evaluating the safety and efficacy of new molecular entities [2, 5].

Other names

SLC22A2SLC47A1SLC47A2OCT2/MATEsRenal organic cation secretory pathway

Inhibition of renal tubular secretion of organic cations through competitive or non-competitive binding to basolateral (OCT2) or apical (MATE1/2-K) transporters, thereby altering the pharmacokinetics and tissue distribution of substrate drugs [1, 2, 12].