SLC22A7 encodes organic anion transporter 2 (OAT2), a sodium-independent organic anion/dimethyldicarboxylate exchanger highly expressed in liver and kidney 1. The transporter mediates uptake of structurally diverse substrates including prostaglandins, nicotinic acid, organic anions (estrone sulfate, bumetanide, allopurinol), and endogenous compounds like creatinine and cGMP 12. Transport operates via counter-transport with intracellular metabolites such as fumarate and succinate 1. SLC22A7 expression is regulated epigenetically by miRNA hsa-miR-29a-3p, which suppresses mRNA stability and translation 3. Genetic variants in SLC22A7 associate with anthracycline-induced cardiotoxicity in pediatric cancer patients, with rs4149178 significantly linked to this adverse effect 45. The rs4149178 variant increases cardiovascular toxicity risk 5-6 fold during chemotherapy 5. SLC22A7 expression is significantly reduced in clear cell renal cell carcinoma, correlating with worse overall and disease-free survival 6. SLC22A7 variants also associate with serum magnesium concentration in type 2 diabetes, suggesting a role in mineral homeostasis 7. Despite its importance in drug transport and metabolism, OAT2 remains understudied compared to other organic anion transporters 8.