Transporters are membrane proteins responsible for the distribution of substances within the body, acting as interfaces between various compartments, thus determining the concentration ratios of substances between these compartments. Consequently, by pharmacologically modulating the function of these transporters, we can shift abnormal compound distributions seen in pathological states, restoring homeostasis and thereby promoting recovery from diseases. For instance, the SGLT2 (SLC5A2) inhibitors, which suppress the reabsorption of glucose in the renal tubules, is an exemplary drug that skews glucose distribution towards the urine, enhancing glucose excretion and rectifying hyperglycemia, establishing its role in diabetes treatment. From another perspective, transporters responsible for nutrient uptake, especially those upregulating in pathogenic cells like cancer cells, become potential drug targets. The amino acid transporter LAT1 (SLC7A5), which is highly expressed with specificity in cancer cells, presents itself as a potential diagnostic and therapeutic target. In this lecture, introducing our research on drug development targeting LAT1 as an example, I would like to discuss the interactions between transporters and compounds as well as the significance of transporters as drug targets.